DP83843 DP83843 PHYTER Literature Number: SNLS021A DP83843BVJE PHYTER General Description Features O bs ol e te The DP83843BVJE is a full feature Physical Layer device -- IEEE 802.3 ENDEC with AUI/10BASE-T transceivers with integrated PMD sublayers to support both 10BASE-T and built-in filters and 100BASE-X Ethernet protocols. -- IEEE 802.3u 100BASE-TX compatible - directly drives standard Category 5 UTP, no need for external This VLSI device is designed for easy implementation of 100BASE-TX transceiver 10/100 Mb/s Ethernet LANs. It interfaces directly to Twisted Pair media through an external transformer or to fiber -- Fully Integrated and fully compliant ANSI X3.263 TPmedia via industry standard electrical/optical fiber PMD PMD physical sublayer which includes adaptive equaltransceivers. This device also interfaces directly to the ization and BLW compensation MAC layer through the IEEE 802.3u standard Media Inde-- IEEE 802.3u 100BASE-FX compatible - connects directpendent Interface (MII), ensuring interoperability between ly to industry standard Electrical/Optical transceivers products from different vendors. -- IEEE 802.3u Auto-Negotiation for automatic speed seThe DP83843 is designed with National Semiconductor's lection advanced CMOS process. Its system architecture is based on the integration of several of National's industry proven -- IEEE 802.3u compatible Media Independent Interface (MII) with Serial Management Interface core technologies: -- Integrated high performance 100 Mb/s clock recovery -- IEEE 802.3 ENDEC with AUI/10BASE-T transceiver circuitry requiring no external filters module to provide the 10 Mb/s functions -- Full Duplex support for 10 and 100 Mb/s data rates -- Clock Recovery/Generator Modules from National's Fast -- MII Serial 10 Mb/s mode Ethernet and FDDI products -- Fully configurable node/switch and 100Mb/s repeater -- FDDI Stream Cipher scrambler/descrambler for modes TP-PMD -- Programmable loopback modes for flexible system diag-- 100BASE-X physical coding sub-layer (PCS) and control nostics logic that integrates the core modules into a dual speed Ethernet physical layer controller -- Flexible LED support -- ANSI X3T12 Compliant TP-PMD Transceiver -- Single register access to complete PHY status technology with Baseline Wander (BLW) compensation -- MDIO interrupt support -- Individualized scrambler seed for 100BASE-TX applications using multiple PHYs -- Low power consumption for multi-port applications -- Small footprint 80-pin PQFP package 10BASE-T or 100BASE-TX MII 10 AND/OR 100 Mb/s ETHERNET MAC OR 100Mb/s REPEATER CONTROLLER DP83843 10/100 Mb/s ETHERNET PHYSICAL LAYER 25 MHz CLOCK MAGNETICS System Diagram RJ-45 10BASE-T or 100BASE-TX STATUS LEDS 100BASE-FX/ AUI ThunderLAN(R) is a registered trademark of Texas Instruments. TWISTERTM is a trademark of National Semiconductor Corporation. TRI-STATE(R) is a registered trademark of National Semiconductor Corporation. (c) 1999 National Semiconductor Corporation www.national.com DP83843BVJE PHYTER July 1999 Block Diagram MII HARDWARE CONFIGURATION PINS RX_CL RXD[3:0] RX_DV RX_ER RX_EN CRS COL MDC MDIO TX_EN TX_ER (REPEATER, SERIAL10, SYMBOL, , AN0, AN1,FXEN PHYAD[4:0]) TXD[3:0] TX_CLK SERIAL MANAGEMENT MII INTERFACE/CONTROL RX_DATA RX_CLK TX_DATA TRANSMIT CHANNELS & STATE MACHINES 100 MB/S SCRAMBLER PARALLEL TO SERIAL REGISTERS MII 10 MB/S PHY ADDRESS NRZ TO MANCHESTER ENCODER AUTO NEGOTIATION LINK PULSE GENERATOR NRZ TO NRZI ENCODER CODE GROUP ALIGNMENT PCS CONTROL DESCRAMBLER 10BASE-T SERIAL TO PARALLEL NRZI TO NRZ DECODER TRANSMIT FILTER FAR-END-FAULT STATE MACHINE O AUTO-NEGOTIATION STATE MACHINE FXTD/AUITD+/- 10 MB/S MANCHESTER TO NRZ DECODER CLOCK RECOVERY 100BASE-X 10/100 COMMON OUTPUT DRIVER TPTD+/- 100 MB/S 4B/5B DECODER NODE/RPTR bs BINARY TO MLT-3 ENCODER RECEIVE CHANNELS & STATE MACHINES ol e 4B/5B ENCODER RX_CLK TX_CLK te TX_DATA RX_DATA TXAR100 LINK PULSE DETECTOR CLOCK RECOVERY MLT-3 TO BINARY DECODER ADAPTIVE EQ AND BLW COMP. RECEIVE FILTER SMART SQUELCH 10/100 COMMON INPUT BUFFER CLOCK GENERATION LED DRIVERS TPRD+/- FXRD/AUIRD+/- LEDS SYSTEM CLOCK REFERENCE 2 FXSD/CD+/- www.national.com Table of Contents 4.0 5.0 9.0 10.0 11.0 O 6.0 8.0 User Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 42 7.1 Link LED While in Force 100Mb/s Good Link . . . 42 7.2 False Link Indication When in Forced 10Mb/s . . 42 7.3 10Mb/s Repeater Mode . . . . . . . . . . . . . . . . . . . 42 7.4 Resistor Value Modifications . . . . . . . . . . . . . . . 42 7.5 Magnetics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 43 7.6 Next Page Toggle Bit Initialization . . . . . . . . . . . 43 7.7 Base Page to Next Page Initial FLP Burst Spacing 43 7.8 100Mb/s FLP Exchange Followed by Quiet . . . . 43 7.9 Common Mode Capacitor for EMI improvement 44 7.10 BAD_SSD Event Lockup . . . . . . . . . . . . . . . . . . 44 Register Block . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 45 8.1 Register Definitions . . . . . . . . . . . . . . . . . . . . . . 45 Electrical Specifications . . . . . . . . . . . . . . . . . . . . . . . 63 9.1 DC Electrical Specification . . . . . . . . . . . . . . . . . 64 9.2 CGM Clock Timing . . . . . . . . . . . . . . . . . . . . . . 66 9.3 MII Serial Management AC Timing . . . . . . . . . . 66 9.4 100 Mb/s AC Timing . . . . . . . . . . . . . . . . . . . . . . 67 9.5 10 Mb/s AC Timing . . . . . . . . . . . . . . . . . . . . . . . 74 9.6 Auto-Negotiation Fast Link Pulse (FLP) Timing 80 9.7 100BASE-X Clock Recovery Module (CRM) Timing 80 9.8 Reset Timing . . . . . . . . . . . . . . . . . . . . . . . . . . 82 9.9 Loopback Timing . . . . . . . . . . . . . . . . . . . . . . . 83 9.10 Isolation Timing . . . . . . . . . . . . . . . . . . . . . . . . 84 Test Conditions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 85 10.1 FXTD/AUITD+/- Outputs (sourcing AUI levels) . 85 10.2 FXTD/AUITD+/- Outputs (sourcing PECL) . . . . . 85 10.3 CMOS Outputs (MII and LED) . . . . . . . . . . . . . . 85 10.4 TPTD+/- Outputs (sourcing 10BASE-T) . . . . . . . 85 10.5 TPTD+/- Outputs (sourcing 100BASE-TX) . . . . . 85 10.6 Idd Measurement Conditions . . . . . . . . . . . . . . . 85 Package Dimensions inches (millimeters) unless otherwise noted . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 87 te 3.0 7.0 ol e 2.0 Pin Descriptions . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.1 MII Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5 1.2 10 Mb/s and 100 Mb/s PMD Interface . . . . . . . . . . 6 1.3 Clock Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . 8 1.4 Device Configuration Interface . . . . . . . . . . . . . . . 8 1.5 LED Interface . . . . . . . . . . . . . . . . . . . . . . . . . . . . 10 1.6 PHY Address Interface . . . . . . . . . . . . . . . . . . . . 11 1.7 Reset . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11 1.8 Power And Ground Pins . . . . . . . . . . . . . . . . . . . 12 1.9 Special Connect Pins . . . . . . . . . . . . . . . . . . . . . . 12 Functional Description . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.1 802.3u MII . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13 2.2 100BASE-TX TRANSMITTER . . . . . . . . . . . . . . . 15 2.3 100BASE-TX RECEIVER . . . . . . . . . . . . . . . . . . 18 2.4 10BASE-T TRANSCEIVER MODULE . . . . . . . . . 22 2.5 100 BASE-FX . . . . . . . . . . . . . . . . . . . . . . . . . . . 24 2.6 AUI . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26 Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28 3.1 Auto-Negotiation . . . . . . . . . . . . . . . . . . . . . . . . . 28 3.2 PHY Address and LEDs . . . . . . . . . . . . . . . . . . . 30 3.3 Half Duplex vs. Full Duplex . . . . . . . . . . . . . . . . . 31 3.4 100 Mb/s Symbol Mode . . . . . . . . . . . . . . . . . . . . 32 3.5 100BASE-FX Mode . . . . . . . . . . . . . . . . . . . . . . . 32 3.6 10 Mb/s Serial Mode . . . . . . . . . . . . . . . . . . . . . . 32 3.7 10 Mb/s AUI Mode . . . . . . . . . . . . . . . . . . . . . . . . 32 3.8 Repeater vs. Node . . . . . . . . . . . . . . . . . . . . . . . . 33 3.9 Isolate Mode . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 3.10 Loopback . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 33 Clock Architecture . . . . . . . . . . . . . . . . . . . . . . . . . . . . 34 4.1 Clock Generation Module (CGM) . . . . . . . . . . . . 34 4.2 100BASE-X Clock Recovery Module . . . . . . . . . . 36 4.3 10 Mb/s Clock Recovery Module . . . . . . . . . . . . . 36 4.4 Reference Clock Connection Options . . . . . . . . . 36 Reset Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.1 Power-up / Reset . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.2 Hardware Reset . . . . . . . . . . . . . . . . . . . . . . . . . . 37 5.3 Software Reset . . . . . . . . . . . . . . . . . . . . . . . . . . 37 DP83843 Application . . . . . . . . . . . . . . . . . . . . . . . . . . 38 6.1 Typical Node Application . . . . . . . . . . . . . . . . . . . 38 6.2 Power And Ground Filtering . . . . . . . . . . . . . . . . 38 6.3 Power Plane Considerations . . . . . . . . . . . . . . . . 38 bs 1.0 3 www.national.com LED_TX/PHYAD[1] LED_COL/PHYAD[0] FXTD-/AUITD- FXTD+/AUITD+ AUIFX_GND FXSD-/CD- AUIFX_VDD FXSD+/CD+ FXRD-/AUIRD- CP_AGND FXRD+/AUIRD+ CP_AVDD CPTW_DVSS NC CPTW_DVDD NC ATP_GND NC NC TWREF Connection Diagram BGREF 61 60 59 58 57 56 55 54 53 52 51 50 49 48 47 46 45 44 43 42 41 40 NC 62 39 THIN/REPEATER 63 38 LED_FDPOL/PHYAD[4] 37 IO_VSS5 36 IO_VDD5 71 CD_VDD0 72 TPTD- 73 74 75 CD_VDD1 76 SUB_GND2 77 TXAR100 78 TR_AVDD 79 TR_AGND 80 DP83843BVJE PHYTER 8 9 10 11 12 13 14 15 16 17 18 19 20 X2 X1 PCS_VSS 7 PCS_VDD 6 IO_VSS1 AN1 5 IO_VDD1 NC 4 AN0 3 SPEED10 2 O 1 RESET bs TPTD+ CD_GND1 te CD_GND0 LED_LINK/PHYAD[3] 35 MDC 34 MDIO 33 TX_CLK 32 IO_VSS4 31 TXD[0] 30 TXD[1] 29 TXD[2] 28 TXD[3] 27 IO_VSS3 26 IO_VDD3 25 TX_EN 24 TX_ER 23 RX_EN 22 CRS/SYMBOL 21 COL/FXEN RX_DV 70 RX_ER SUB_GND1 RX_CLK 69 IO_VSS2 68 SERIAL10 IO_VDD2 67 RXD[0] TPRD+ TW_AVDD RXD[1] 66 RXD[2] 65 VCM_CAP ol e 64 TPRD- RXD[3] TW_AGND LED_RX/PHYAD[2] Order Number DP83843BVJE NS Package Number VJE80 4 www.national.com 1.0 Pin Descriptions The DP83843 pins are classified into the following interface -- DEVICE CONFIGURATION INTERFACE categories. Each interface is described in the sections that -- LED INTERFACE follow. -- PHY ADDRESS INTERFACE -- MII INTERFACE -- RESET -- 10/100 Mb/s PMD INTERFACE -- POWER AND GROUND PINS -- CLOCK INTERFACE -- SPECIAL CONNECT PINS 1.1 MII Interface Signal Name Type Pin # Description I 35 MANAGEMENT DATA CLOCK: Synchronous clock to the MDIO management data input/output serial interface which may be asynchronous to transmit and receive clocks. The maximum clock rate is 2.5 MHz. There is no minimum clock rate. MDIO I/O, Z 34 MANAGEMENT DATA I/O: Bi-directional management instruction/data signal that may be sourced by the station management entity or the PHY. This pin requires a 1.5 k pullup resistor. CRS I/O, Z 22 CARRIER SENSE: This pin is asserted high to indicate the presence of carrier due to receive or transmit activities in 10BASE-T or 100BASE-X Half Duplex modes. te MDC (SYMBOL) In Repeater or Full Duplex mode, this pin is asserted high to indicate the presence of carrier due only to receive activity. In Symbol mode this pin indicates the signal detect status of the TP-PMD (active high). (FXEN) COLLISION DETECT: Asserted high to indicate detection of collision condition (assertion of CRS due to simultaneous transmit and receive activity) in 10 Mb/s and 100 Mb/s Half Duplex modes. ol e I/O, Z 21 COL While in 10BASE-T Half Duplex mode with Heartbeat enabled (bit 7, register 18h), this pin is also asserted for a duration of approximately 1 s at the end of transmission to indicate heartbeat (SQE test). During Repeater mode the heartbeat function is disabled. In Full Duplex mode, for 10 Mb/s or 100 Mb/s operation, this signal is always logic 0. There is no heartbeat function during 10 Mb/s full duplex operation. TX_CLK O, Z 33 TRANSMIT CLOCK: Transmit clock output from the DP83843: bs 25 MHz nibble transmit clock derived from Clock Generator Module's (CGM) PLL in 100BASE-TX mode. 2.5 MHz transmit clock in 10BASE-T Nibble mode. 10 MHz transmit clock in 10BASE-T Serial mode. TXD[3] TXD[2] TXD[1] 28 29 30 31 O TXD[0] I TX_EN TX_ER I I 25 24 (TXD[4]) TRANSMIT DATA: Transmit data MII input pins that accept nibble data during normal nibble-wide MII operation at either 2.5 MHz (10BASE-T mode) or 25 MHz (100BASE-X mode). In 10 Mb/s Serial mode, the TXD[0] pin is used as the serial data input pin, and TXD[3:1] are ignored. TRANSMIT ENABLE: Active high input indicates the presence of valid nibble data on TXD[3:0] for both 100 Mb/s or 10 Mb/s nibble mode. In 10 Mb/s Serial mode, active high indicates the presence of valid 10 Mb/s data on TXD[0]. TRANSMIT ERROR: In 100 Mb/s mode, when this signal is high and TX_EN is active the HALT symbol is substituted for the actual data nibble. In 10 Mb/s mode, this input is ignored. In Symbol mode (Symbol=0), TX_ER becomes the TXD [4] pin which is the MSB for the transmit 5-bit data symbol. RX_CLK O, Z 18 RECEIVE CLOCK: Provides the recovered receive clock for different modes of operation: 25 MHz nibble clock in 100 Mb/s mode 2.5 MHz nibble clock in 10 Mb/s nibble mode 10 MHz receive clock in 10 Mb/s serial mode 5 www.national.com 1.0 Pin Descriptions (Continued) Signal Name Type RXD[3] O, Z Pin # Description 12 RXD[2] 13 RXD[1] 14 RXD[0] 15 RECEIVE DATA: Nibble wide receive data (synchronous to RX_CLK, 25 MHz for 100BASE-X mode, 2.5 MHz for 10BASE-T nibble mode). Data is driven on the falling edge of RX_CLK. In 10 Mb/s serial mode, the RXD[0] pin is used as the data output pin which is also clocked out on the falling edge of RX_CLK. During 10 Mb/s serial mode RXD[3:1] pins become don't cares. RX_EN I 23 RECEIVE ENABLE: Active high enable for receive signals RXD[3:0], RX_CLK, RX_DV and RX_ER. A low on this input places these output pins in the TRI-STATE mode. For normal operation in a node or switch application, this pin should be pulled high. For operation in a repeater application, this pin may be connected to a repeater controller. RX_ER O, Z 19 RECEIVE ERROR: Asserted high to indicate that an invalid symbol has been detected within a received packet in 100 Mb/s mode. (RXD[4]) In Symbol mode (Symbol = 0), RX_ER becomes RXD[4] which is the MSB for the receive 5-bit data symbol. O, Z 20 RECEIVE DATA VALID: Asserted high to indicate that valid data is present on RXD[3:0] for nibble mode and RXD[0] for serial mode. Data is driven on the falling edge of RX_CLK. te RX_DV This pin is not meaningful during Symbol mode. 1.2 10 Mb/s and 100 Mb/s PMD Interface Type TPTD- O TPTD+ (MLT-3 or Pin # Description ol e Signal Name 73 74 TRANSMIT DATA: Differential common output driver. This differential output is configurable to either 10BASE-T or 100BASE-TX signaling: 10BASE-T: Transmission of Manchester encoded 10BASE-T packet data as well as Link Pulses (including Fast Link Pulses for Auto-Negotiation purposes.) 10BASE-T) 100BASE-TX: Transmission of ANSI X3T12 compliant MLT-3 data. TPRDTPRD+ bs The DP83843 will automatically configure this common output driver for the proper signal type as a result of either forced configuration or Auto-Negotiation. I 65 (MLT-3 67 RECEIVE DATA: Differential common input buffer. This differential input can be configured to accept either 100BASE-TX or 10BASE-T signaling: 10BASE-T: Reception of Manchester encoded 10BASE-T packet data as well as normal Link Pulses (including Fast Link Pulses for Auto-Negotiation purposes.) or 10BASE-T) O 100BASE-TX: Reception of ANSI X3T12 compliant scrambled MLT-3 data. The DP83843 will automatically configure this common input buffer to accept the proper signal type as a result of either forced configuration or Auto-Negotiation. FXTD-/AUITD- O 44 FXTD+/AUITD+ (PECL 43 or AUI) 100BASE-FX or 10 Mb/s AUI TRANSMIT DATA: This configurable output driver supports either 125 Mb/s PECL, for 100BASE-FX applications, or 10 Mb/s AUI signaling. When configured as a 100BASE-FX transmitter this output sources 100BASE-FX standard compliant binary data for direct connection to an optical transceiver. This differential output is enabled only during 100BASE-FX device configuration (see pin definition for FXEN.) When configured as an AUI driver this output sources AUI compatible Manchester encoded data to support typical 10BASE2 or 10BASE5 products. 6 www.national.com 1.0 Pin Descriptions (Continued) Signal Name Type Pin # FXRD-/AUIRD- I 49 FXRD+/AUIRD+ (PECL 50 or Description 100BASE-FX or 10 Mb/s AUI RECEIVE DATA: This configurable input buffer supports either 125 Mb/s PECL, for 100BASE-FX applications, or 10 Mb/s AUI signaling. When configured as a 100BASE-FX receiver this input accepts 100BASE-FX standard compliant binary data direct from an optical transceiver. This differential input is enabled only during 100BASE-FX device configuration (see the pin definition for FXEN). AUI) When configured as an AUI buffer this input receives AUI compatible Manchester data to support typical 10BASE2 or 10BASE5 products. FXSD-/CD- I 47 FXSD+/CD+ (PECL 48 or SIGNAL DETECT or AUI COLLISION DETECT: This configurable input buffer supports either 125 Mb/s PECL, for 100BASE-FX applications, or 10 Mb/s AUI signaling. te When configured as a 100BASE-FX receiver this input accepts indication from the 100BASE-FX PMD transceiver upon detection of a receive signal from the fiber media. This pin is only active during 100BASE-FX operation(see the pin definition for FXEN). AUI) When configured as an AUI buffer this input receives AUI compatible Manchester data to support typical 10BASE2 or 10BASE5 products. THIN I/O, Z 63 TXAR100 ol e (REPEATER) THIN AUI MODE: This output allows for control of an external CTI coaxial transceiver connected through the AUI. This pin is controlled by writing to bit 3 of the 10BTSCR register (address 18h). The THIN pin may also be used as a user configurable output control pin. I (current reference) 78 100 Mb/s TRANSMIT AMPLITUDE REFERENCE CONTROL: Reference current allowing adjustment of the TPTD+/- output amplitude during 100BASE-TX operation. bs By placing a resistor between this pin and ground or VCC, a reference current is set up which dictates the output amplitude of the 100BASE-TX MLT-3 transmit signal. Connecting a resistor to VCC will increase the transmit amplitude while connecting a resistor to ground will decrease the transmit amplitude. While the value of the resistor should be evaluated on a case by case bases, the DP83843 was designed to produce an amplitude close to the required range of 2V pk-pk differential 5% as measured across TD+/- while driving a typical 100 differential load without a resistor connected to this pin. Therefore this pin is allowed to float in typical applications. This current reference is only recognized during 100BASE-TX operation and has no effect during100BASE-FX,10BASE-T, or AUI modes of operation. TWREF 60 TWISTER REFERENCE RESISTOR: External reference current adjustment, via a resistor to TW_AGND, which controls the TP-PMD receiver equalization levels. The value of this resistor is 70k 1%. I (current reference) 61 BANDGAP REFERENCE: External current reference resistor for internal bandgap circuitry. The value of this resistor is 4.87k 1%. I 66 COMMON MODE BYPASS CAPACITOR: External capacitor to improve common mode filtering for the receive signal. It is recommended that a .0033F in parallel with a .10F capacitor be used, see Figure 23. O BGREF I VCM_CAP 7 www.national.com 1.0 Pin Descriptions (Continued) 1.3 Clock Interface Signal Name Type Pin # Description X1 I 9 CRYSTAL/OSCILLATOR INPUT: This pin is the primary clock reference input for the DP83843 and must be connected to a 25 MHz 0.005% (50 ppm) clock source. The DP83843 device supports either an external crystal resonator connected across pins X1 and X2, or an external CMOS-level oscillator source connected to pin X1 only. For 100 Mb/s repeater applications, X1 should be tied to the common 25 MHz transmit clock reference. Refer to section 4.4 for further detail relating to the clock requirements of the DP83843. Refer to section 4.0 for clock source specifications. X2 O 8 CRYSTAL/OSCILLATOR OUTPUT PIN: This pin is used in conjunction with the X1 pin to connect to an external 25 MHz crystal resonator device. This pin must be left unconnected if an external CMOS oscillator clock source is utilized. For more information see the definition for pin X1. Refer to section 2.8 for further detail. 1.4 Device Configuration Interface AN0 Type I Pin # 4 Description te Signal Name AN0: This is a three level input pin (1, M, 0) that works in conjunction with the AN1 pin to control the forced or advertised operating mode of the DP83843 according to the following table. The value on this pin is set by connecting the input pin to GND (0), VCC (1), or leaving it unconnected (M.) The unconnected state, M, refers to the mid-level (VCC/2) set by internal resistors. The value set at this input is latched into the DP83843 at power-up/reset. AN1 0 1 M M AN0 M M 0 1 Forced Mode 10BASE-T, Half-Duplex without Auto-Negotiation 10BASE-T, Full Duplex without Auto-Negotiation 100BASE-X, Half-Duplex without Auto-Negotiation 100BASE-X, Full Duplex without Auto-Negotiation AN1 M AN0 M 0 0 Advertised Mode All capable (i.e. Half-Duplex & Full Duplex for 10BASE-T and 100BASE-TX) advertised via Auto-Negotiation 10BASE-T, Half-Duplex & Full Duplex advertised via AutoNegotiation 100BASE-TX, Half-Duplex & Full Duplex advertised via Auto-Negotiation 10BASE-T & 100BASE-TX, Half-Duplex advertised via AutoNegotiation 10 BASE-T, Half-Duplex advertised via Auto-Negotiation I (3-level) 3 O AN1 bs ol e (3-level) 0 1 1 0 1 1 AN1: This is a three-level input pin (i.e., 1, M, 0) that works in conjunction with the AN0 pin to control the forced or advertised operating mode of the DP83843 according to the table given in the AN0 pin description above. The value on this pin is set by connecting the input pin to GND (0), VCC (1), or leaving it unconnected (M.) The value at this input is latched into the DP83843 at power-up, hardware or software reset. 8 www.national.com 1.0 Pin Descriptions (Continued) Signal Name REPEATER Type I/O Pin # 63 Description REPEATER/NODE MODE: Selects 100 Mb/s Repeater mode when set high and node mode when set low. When set in Repeater mode the DP83843 only supports 100 Mb/s data rates. In Repeater mode (or Node mode with Full Duplex configured), the Carrier Sense (CRS) output from the DP83843 is asserted due to receive activity only. In Half Duplex Node mode, CRS is asserted due to either receive or transmit activity. During repeater mode the heartbeat function(SQE) is forced off. (THIN) The Carrier Integrity Monitor (CIM) function is automatically enabled when this pin is set high (repeater mode) and disabled when this pin is set low (node mode) in order to facilitate 802.3u CIM requirements. There is an internal pullup resistor for this pin which is active during the powerup/reset period. If this pin is left floating externally, then the device will configure to 100 Mb/s Repeater mode as a result of power-up/reset. This pin must be externally pulled low (typically 10 k) in order to configure the DP83843 for Node operation. SYMBOL/ I/O, Z te The value of this input is latched into the DP83843 at power-up, hardware or software reset. 22 SYMBOL MODE: This active low input allows 100 Mb/s transmit and receive data streams to bypass all of the transmit and receive operations when set low. Note that the PCS signals (CRS, RX_DV, RX_ER, and COL) have no meaning during this mode. During Symbol operation, pins RX_ER/RXD[4] and TX_ER/TXD[4] are used as the MSB of the 5 bit RX and TX data symbols. (CRS) ol e There is an internal pullup resistor for this pin which is active during the powerup/reset period. If this pin is left floating externally, then the device will configure to normal mode as a result of power-up/reset. This pin must be externally pulled low (typically 10 k) in order to configure the DP83843 for Symbol mode operation. In Symbol mode this pin will indicate the signal detect status of the TP-PMD (active high). This mode has no effect on 10Mb/s operation. The value at this input is latched into the DP83843 at power-up, hardware or software reset. I 69 10BASE-T SERIAL/NIBBLE SELECT: With this active low input selected, transmit and receive data are exchanged serially at a 10 MHz clock rate on the least significant bits of the nibble-wide MII data buses, pins TXD[0] and RXD[0] respectively. This mode is intended for use with the DP83843 connected to a MAC using a 10 Mb/s serial interface. Serial operation is not supported in 100 Mb/s mode, therefore this input is ignored during 100 Mb/s operation. bs SERIAL10 O There is an internal pullup resistor for this pin which is active during the powerup/reset period. If this pin is left floating externally, then the device will configure to normal mode as a result of power-up/reset. This pin must be externally pulled low (typically 10 k) in order to configure the DP83843 for Serial MII operation when running at 10 Mb/s. FXEN/ (COL) I/O, Z 21 The value at this input is latched into the DP83843 at power-up, hardware or software reset. FIBER ENABLE: This active low input allows 100 Mb/s transmit and receive data streams to bypass the scrambler and descrambler circuits when selected. All PCS signaling remains active and unaffected during this mode. During this mode, the internal 100 Mb/s transceiver is disabled, and NRZI data is transmitted and received via the FXTD/AUITD+/- and FXRD/AUIRD+/- pins. There is an internal pullup resistor for this pin which is active during the powerup/reset period. If this pin is left floating externally, then the device will configure to normal mode as a result of power-up/reset. This pin must be externally pulled low (typically 10 k) in order to configure the DP83843 for 100BASE-FX operation. The value at this input is latched into the DP83843 at power-up, hardware or software reset. 9 www.national.com 1.0 Pin Descriptions (Continued) 1.5 LED Interface input is resistively pulled low then the corresponding LED output will be configured as an active high driver. Conversely, if a given PHYAD input is resistively pulled high then the corresponding LED output will be configured as an active low driver (refer to section 5.0.1 for further details). Note that these outputs are standard CMOS voltage drivers and not open-drain. These outputs can be used to drive LEDs directly, or can be used to provide status information to a network management device. Refer to section 2.2 for a description of how to generate LED indication of 100 Mb/s mode. The active state of each LED output driver is dependent on the logic level sampled by the corresponding PHY address input upon power-up/reset. For example, if a given PHYAD Signal Name LED_COL Type I/O Pin # 42 (PHYAD[0]) Description COLLISION LED: Indicates the presence of collision activity for 10 Mb/s and 100 Mb/s Half Duplex operation. This LED has no meaning for 10 Mb/s or 100 Mb/s Full Duplex operation and will remain deasserted. During 10 Mb/s half duplex mode this pin will be asserted after data transmission due to the heartbeat function. The DP83843 incorporates a "monostable" function on the LED_COL output. This ensures that even collisions generate adequate LED ON time (approximately 50 ms) for visibility. I/O 41 (PHYAD[1]) TRANSMIT LED: Indicates the presence of transmit activity for 10 Mb/s and 100 Mb/s operation. te LED_TX ol e If bit 7 (LED_Trans_MODE) of the PHYCTRL register (address 19h) is set high, then the LED_TX pin function is changed to indicate the status of the Disconnect function as defined by the state of bit 4 (CIM_STATUS) in the 100 Mb/s PCS configuration & status register (address 16h). See register definition for complete description of alternative operation. The DP83843 incorporates a "monostable" function on the LED_TX output. This ensures that even minimum size packets generate adequate LED ON time (approximately 50 ms) for visibility. LED_RX I/O (PHYAD[2]) 40 RECEIVE LED: Indicates the presence of any receive activity for 10 Mb/s and 100 Mb/s operation. See register definitions(PHYCTRL register and PCSR register) for complete descriptions of alternative operation. The DP83843 incorporates a "monostable" function on the LED_RX output. This ensures that even minimum size packets generate adequate LED active time (approximately 50 ms) for visibility. I/O 39 LINK LED: Indicates good link status for 10 Mb/s and 100 Mb/s operation. bs LED_LINK In 100BASE-T mode, link is established as a result of input receive amplitude compliant with TP-PMD specifications which will result in internal generation of Signal Detect as well as an internal signal from the Clock Recovery Module (cypher & sync). LED_LINK will assert after these internal signals have remained asserted for a minimum of 500s. Once Link is established, then cipher & sync are no longer sampled and the Link will remain valid as long as Signal Detect is valid. LED_LINK will deassert immediately following the deassertion of the internal Signal Detect. O (PHYAD[3]) 10 Mb/s link is established as a result of the reception of at least seven consecutive normal Link Pulses or the reception of a valid 10BASE-T packet which will cause the assertion of LED_LINK. LED_LINK will deassert in accordance with the Link Loss Timer as specified in IEEE 802.3. In 100BASE-FX mode, link is established as a result of the assertion of the Signal detect input to the DP83843. LED_LINK will assert after Signal Detect has remained asserted for a minimum of 500S. LED_LINK will deassert immediately following the deassertion of signal detect. The link function is disabled during AUI operation and LED_LINK is asserted. LED_FDPOL I/O 38 (PHYAD[4]) FULL DUPLEX LED: Indicates Full Duplex mode status for 10 Mb/s or 100 Mb/s operation. This pin can be configured to indicate Polarity status for 10 Mb/s operation. If bit 6 (LED_DUP_MODE) in the PHYCTRL Register (address 19h) is deasserted, the LED_FDPOL pin function is changed to indicate Polarity status for 10 Mb/s operation. The DP83843 automatically compensates for 10BASE-T polarity inversion. 10BASE-T polarity inversion is indicated by the assertion of LED_FDPOL. SPEED10 O 5 SPEED 10 Mb/s: Indicates 10 Mb/s operation when high. Indicates 100 Mb/s operation when low. This pin can be used to drive peripheral circuitry such as an LED indicator. 10 www.national.com 1.0 Pin Descriptions (Continued) 1.6 PHY Address Interface (00000) will result in a PHY isolation condition as a result of power-on/reset, as specified in IEEE 802.3u. The DP83843 PHYAD[4:0] inputs provide up to 32 unique PHY address options. An address selection of all zeros Signal Name Type PHYAD[0] Pin # I/O 42 (LED_COL) Description PHY ADDRESS [0]: PHY address sensing pin for multiple PHY applications. PHY address sensing is achieved by strapping a pull-up/pull-down resistor (typically 10 k) to this pin as required. The pull-up/pull-down status of this pin is latched into the PHYCTRL register (address 19h, bit 0) during power up/reset. PHYAD[1] I/O 41 (LED_TX) PHY ADDRESS [1]: PHY address sensing pin for multiple PHY applications. PHY address sensing is achieved by strapping a pull-up/pull-down resistor (typically 10 k) to this pin as required. The pull-up/pull-down status of this pin is latched into the PHYCTRL register (address 19h, bit 1) during power up/reset. I/O 40 (LED_RX) PHY ADDRESS [2]: PHY address sensing pin for multiple PHY applications. PHY address sensing is achieved by strapping a pull-up/pull-down resistor (typically 10 k) to this pin as required. te PHYAD[2] The pull-up/pull-down status of this pin is latched into the PHYCTRL register (address 19h, bit 2) during power up/reset. PHYAD[3] I/O 39 PHY ADDRESS [3]: PHY address sensing pin for multiple PHY applications. PHY address sensing is achieved by strapping a pull-up/pull-down resistor (typically 10 k) to this pin as required. ol e (LED_LINK) The pull-up/pull-down status of this pin is latched into the PHYCTRL register (address 19h, bit 3) during power up/reset. PHYAD[4] I/O 38 (LED_FDPOL) PHY ADDRESS [4]: PHY address sensing pin for multiple PHY applications. PHY address sensing is achieved by strapping a pull-up/pull-down resistor (typically 10 k) to this pin as required. The pull-up/pull-down status of this pin is latched into the PHYCTRL register (address 19h, bit 4) during power up/reset. bs 1.7 Reset Signal Name Type I Pin # 1 Description RESET: Active high input that initializes or reinitializes the DP83843. Asserting this pin will force a reset process to occur which will result in all internal registers reinitializing to their default states as specified for each bit in section 7.0, and all strapping options are reinitialized. Refer to section 5.0 for further detail regarding reset. O RESET 11 www.national.com 1.0 Pin Descriptions (Continued) 1.8 Power And Ground Pins supply pairs. This grouping allows for optimizing the layout and filtering of the power and ground supplies to this The power (VCC) and ground (GND) pins of the DP83843 device. are grouped in pairs into three categories--TTL/CMOS Input pairs, Transmit/Receive supply pairs, and Internal Signal Name Pin # Description TTL/CMOS INPUT/OUTPUT SUPPLY PAIRS IO_VDD1 6 IO_VSS1 7 TTL Input/Output Supply #1 IO_VDD2 16 IO_VSS2 17 IO_VDD3 26 IO_VSS3 27 IO_VSS4 32 TTL Input/Output Supply #4 IO_VDD5 36 TTL Input/ Output Supply #5 IO_VSS5 37 PCS_VDD 10 PCS_VSS 11 TTL Input/Output Supply #2 te TTL Input /Output Supply #3 Physical Coding Sublayer Supply TRANSMIT/RECEIVE SUPPLY PAIRS 46 AUI Power Supply ol e AUIFX_VDD AUIFX_GND 45 TR_AVDD 79 TR_AGND 10 Mb/s Supply 80 TW_AVDD 68 TW_AGND 100 Mb/s Power Supply 64 CD_VDD0 72 71 bs CD_GND0 Common Driver Supply CD_VDD1 76 CD_GND1 75 Common Driver Supply INTERNAL SUPPLY PAIRS 52 CP_AGND 51 CPTW_DVDD 54 CPTW_DVSS 53 ATP_GND 57 100BASE-T PMD Supply SUB_GND1, 70 100BASE-T PMD Supply SUB_GND2 77 O CP_AVDD CRM/CGM Supply CRM/CGM Supply 1.9 Special Connect Pins Signal Name NC Type Pin # 2,55,56, 58,59, 62 Description NO CONNECT: These pins are reserved for future use. Leave them unconnected (floating). 12 www.national.com 2.0 Functional Description 2.1 802.3u MII and no minimum rate. The MDIO line is bi-directional and may be shared by up to 32 devices. The MDIO frame format is shown in Table 1. The DP83843 incorporates the Media Independent Interface (MII) as specified in clause 22 of the IEEE 802.3u standard. This interface may be used to connect PHY devices to a 10/100 Mb/s MAC or a 100 Mb/s repeater controller. This section describes both the serial MII management interface as well as the nibble wide MII data interface. The MDIO pin requires a pull-up resistor (1.5 k) which, during IDLE and turnaround, will pull MDIO high. In order to initialize the MDIO interface, the Station Management Entity (SME) sends a sequence of 32 contiguous logic ones on MDIO to provide the DP83843 with a sequence that can be used to establish synchronization. This preamble may be generated either by driving MDIO high for 32 consecutive MDC clock cycles, or by simply allowing the MDIO pull-up resistor to pull the MDIO pin high during which time 32 MDC clock cycles are provided. In addition 32 MDC clock cycles should be used if an invalid start, op code, or turnaround bit is detected. The management interface of the MII allows the configuration and control of multiple PHY devices, the gathering of status and error information, and the determination of the type and abilities of the attached PHY(s). The nibble wide MII data interface consists of a receive bus and a transmit bus each with control signals to facilitate data transfer between the PHY and the upper layer (MAC or repeater). The serial MII specification defines a set of thirty-two 16-bit status and control registers that are accessible through the serial management data interface pins MDC and MDIO. The DP83843 implements all the required MII registers as well as several optional registers. These registers are fully described in Section 7. A description of the serial management access protocol follows. te The DP83843 waits until it has received this preamble The DP83843 supports the TI ThunderLAN(R) MII interrupt sequence before responding to any other transaction. function. For further information please contact your local Once the DP83843 serial management port has initialized National sales representative. no further preamble sequencing is required until after a power-on/reset has occurred. 2.1.1 Serial Management Register Access The Start code is indicated by a <01> pattern. This assures the MDIO line transitions from the default idle line state. ol e Turnaround is an idle bit time inserted between the Register Address field and the Data field. To avoid contention, no device actively drives the MDIO signal during the first bit of Turnaround during a read transaction. The addressed DP83843 drives the MDIO with a zero for the second bit of turnaround and follows this with the required data. Figure 2 2.1.2 Serial Management Access Protocol shows the timing relationship between MDC and the MDIO The serial control interface consists of two pins, Manage- as driven/received by the Station Management Entity and ment Data Clock (MDC) and Management Data Input/Out- the DP83843 (PHY) for a typical register read access. put (MDIO). MDC has a maximum clock rate of 2.5 MHz Table 1. Typical MDIO Frame Format bs MII Management Serial Protocol Read Operation <01><10> Write Operation <01><01> <10> MDC MDIO Z O (SME) Z 0 1 0 1 0 1 1 0 0 0 0 0 0 0 1 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 0 Z Idle Start Opcode (Write) PHY Address (PHYAD = 0Ch) Register Address (00h = BMCR) Register Data TA Z Idle Figure 1. Typical MDC/MDIO Write Operation MDC MDIO Z Z (SME) Z MDIO Z (PHY) Z Idle 0 1 1 0 0 1 1 0 0 0 0 0 0 0Z 0 0 0 1 1 0 0 0 1 0 0 0 0 0 0 0 0 Start Opcode (Read) PHY Address (PHYAD = 0Ch) Register Address (00h = BMCR) TA Register Data Z Idle Figure 2. Typical MDC/MDIO Read Operation 13 www.national.com 2.0 Functional Description (Continued) occur during half-duplex operation when both a transmit and receive operation occur simultaneously. For write transactions, the Station Management Entity writes data to an addressed DP83843 eliminating the requirement for MDIO Turnaround. The Turnaround time is filled by the management entity inserting <10> for these two bits. Figure 1 shows the timing relationship for a typical MII register write access. 2.1.6 Collision Detect For Half Duplex, a 10BASE-T or 100BASE-X collision is detected when the receive and transmit channels are active simultaneously. Collisions are reported by the COL signal on the MII. 2.1.3 Preamble Suppression The DP83843 supports a Preamble Suppression mode as indicated by a one in bit 6 of the Basic Mode Status Register (BMSR, address 01h). If the Station Management Entity (i.e. MAC or other management controller) determines that all PHYs in the system support Preamble Suppression by returning a one in this bit, then the Station Management Entity need not generate preamble for each management transaction. 2.1.4 PHY Address Sensing When heartbeat is enabled (only applicable to 10 Mb/s operation), approximately 1 s after the transmission of each packet, a Signal Quality Error (SQE) signal of approximately 10 bit times is generated (internally) to indicate successful transmission. SQE is reported as a pulse on the COL signal of the MII. 2.1.7 Carrier Sense Carrier Sense (CRS) may be asserted due to receive activity, once valid data is detected via the Smart Squelch function during 10 Mb/s operation. ol e While the DP83843 requires an initial preamble sequence of 32 bits for management initialization, it does not require a full 32 bit sequence between each subsequent transaction. A minimum of one idle bit between management transactions is required as specified in IEEE 802.3u. If a collision occurs during a receive operation, it is immediately reported by the COL signal. te The DP83843 requires a single initialization sequence of 32 bits of preamble following power-up/hardware reset. This requirement is generally met by the mandatory pull-up resistor on MDIO in conjunction with a continuous MDC, or the management access made to determine whether Preamble Suppression is supported. If the DP83843 is transmitting in 10 Mb/s mode when a collision is detected, the collision is not reported until seven bits have been received while in the collision state. This prevents a collision being reported incorrectly due to noise on the network. The COL signal remains set for the duration of the collision. The DP83843 can be set to respond to any of the possible 32 PHY addresses. Each DP83843 connected to a common serial MII must have a unique address. It should be noted that while an address selection of all zeros <00000> will result in PHY Isolate mode, this will not effect serial management access. For 10 Mb/s Half Duplex operation, CRS is asserted during either packet transmission or reception. For 10 Mb/s Full Duplex operation, CRS is asserted only due to receive activity. CRS is deasserted following an end of packet. bs In Repeater mode (pin 63/bit 9, register address 19h), CRS The DP83843 provides five PHY address pins, the state of is only asserted due to receive activity. which are latched into the PHYCTRL register (address 2.1.8 MII Isolate Mode 19h) at system power-up/reset. These pins are described A 100BASE-X PHY connected to the mechanical MII interin Section 2.8. For further detail relating to the latch-in timface specified in IEEE 802.3u is required to have a default ing requirements of the PHY address pins, as well as the value of one in bit 10 of the Basic Mode Control Register other hardware configuration pins, refer to Section 3.10. (BMCR, address 00h). The DP83843 will set this bit to one 2.1.5 Nibble-wide MII Data Interface if the PHY Address is set to 00000 upon power-up/hardClause 22 of the IEEE 802.3u specification defines the ware reset. Otherwise, the DP83843 will set this bit to zero Media Independent Interface. This interface includes a upon power-up/hardware reset. dedicated receive bus and a dedicated transmit bus. These two data buses, along with various control and indicate signals, allow for the simultaneous exchange of data between the DP83843 and the upper layer agent (MAC or repeater). O With bit 10 in the BMCR set to one, the DP83843 does not respond to packet data present at TXD[3:0], TX_EN, and TX_ER inputs and presents a high impedance on the TX_CLK, RX_CLK, RX_DV, RX_ER, RXD[3:0], COL, and The receive interface consists of a nibble wide data bus CRS outputs. The DP83843 will continue to respond to all RXD[3:0], a receive error signal RX_ER, a receive data serial management transactions over the MII. valid flag RX_DV, and a receive clock RX_CLK for synchro- While in Isolate mode, the TPTD+/- and FXTD/AUITD+/- nous transfer of the data. The receive clock can operate at outputs are dependent on the current state of Auto-Negotieither 2.5 MHz to support 10 Mb/s operation modes or at ation. The DP83843 can Auto-Negotiate or parallel detect 25 MHz to support 100 Mb/s operational modes. to a specific technology depending on the receive signal at The transmit interface consists of a nibble wide data bus the TPRD+/- inputs. A valid link can be established for TXD[3:0], a transmit error flag TX_ER, a transmit enable either TPRD or FXRD/AUI even when the DP83843 is in control signal TX_EN, and a transmit clock TX_CLK which Isolate mode. runs at either 2.5 MHz or 25 MHz. It is recommended that the user have a basic understandAdditionally, the MII includes the carrier sense signal CRS, ing of clause 22 of the 802.3u standard. as well as a collision detect signal COL. The CRS signal asserts to indicate the reception of data from the network or as a function of transmit data in Half Duplex mode. The COL signal asserts as an indication of a collision which can 14 www.national.com 2.0 Functional Description (Continued) 2.2 100BASE-TX TRANSMITTER -- Code-group Encoder and Injection block (bypass option) -- Scrambler block (bypass option) -- NRZ to NRZI encoder block -- Binary to MLT-3 converter / Common Driver The bypass option for the functional blocks within the 100BASE-X transmitter provides flexibility for applications such as 100 Mb/s repeaters where data conversion is not always required. The DP83843 implements the 100BASEX transmit state machine diagram as specified in the IEEE 802.3u Standard, Clause 24. The 100BASE-TX transmitter consists of several functional blocks which convert synchronous 4-bit nibble data, as provided by the MII, to a scrambled MLT-3 125 Mb/s serial data stream. Because the 100BASE-TX TP-PMD is integrated, the differential output pins, TPTD+/-, can be directly routed to the AC coupling magnetics. The block diagram in Figure 3 provides an overview of each functional block within the 100BASE-TX transmit section. The Transmitter section consists of the following functional blocks: TXD[3:0] / TX_ER te TX_CLK 25MHZ ol e CODE-GROUP ENCODER & INJECTOR BP_4B5B MUX SCRAMBLER MUX bs BP_SCR BP_TX MUX O PARALLEL TO SERIAL NRZ TO NRZI ENCODER 100BASE-X LOOPBACK BINARY TO MLT-3 / COMMON DRIVER TPTD +/- Figure 1. 100BASE-TX Transmit Block Diagram - Code-group Encoding and Injection 15 www.national.com 2.0 Functional Description (Continued) 2.2.1 Scrambler The code-group encoder converts 4 bit (4B) nibble data generated by the MAC into 5 bit (5B) code-groups for transmission. This conversion is required to allow control data to be combined with packet data code-groups. Refer to Table 2 for 4B to 5B code-group mapping details. The scrambler is required to control the radiated emissions at the media connector and on the twisted pair cable (for 100BASE-TX applications). By scrambling the data, the total energy launched onto the cable is randomly distribThe code-group encoder substitutes the first 8 bits of the uted over a wide frequency range. Without the scrambler, MAC preamble with a J/K code-group pair (11000 10001) energy levels at the PMD and on the cable could peak upon transmit. The code-group encoder continues to beyond FCC limitations at frequencies related to repeating replace subsequent 4B preamble and data nibbles with 5B sequences (i.e., continuous transmission of IDLEs). corresponding 5B code-groups. At the end of the transmit The scrambler is configured as a closed loop linear feedpacket, upon the deassertion of Transmit Enable signal back shift register (LFSR) with an 11-bit polynomial. The from the MAC or Repeater, the code-group encoder injects output of the closed loop LFSR is combined with the NRZ the T/R code-group pair (01101 00111) indicating the end 5B data from the code-group encoder via an X-OR logic of frame. function. The result is a scrambled data stream with suffiAfter the T/R code-group pair, the code-group encoder continuously injects IDLEs into the transmit data stream until the next transmit packet is detected (reassertion of Transmit Enable). ol e te cient randomization to decrease radiated emissions at certain frequencies by as much as 20 dB. The DP83843 uses the PHYID as determined by the PHYAD [4:0] pins to set a unique seed value for the scrambler so that the total energy The DP83843 also incorporates a special injection function produced by a multi-PHY application (i.e. repeater) distribwhich allows for fixed transmission of special repeating pat- utes the energy out of phase across the spectrum and terns for testing purposes. These special patterns are not helps to reduce overall electro-magnetic radiation. delimited with Start of Stream Delimiter (SSD) or End of The scrambler is automatically bypassed when the Stream Delimiter (ESD) code-groups and should not be DP83843 is placed in FXEN mode via hardware or, alternaenabled during normal network connectivity. tively, controlled by bit 12 of LBR (address 17h) via softThese patterns, selectable via bits [8:7] of PCRS (address ware. 16h), include: 2.2.2 NRZ to NRZI Encoder 8=0, 7=0: Normal operation (injection disabled) After the transmit data stream has been scrambled and serialized, the data must be NRZI encoded in order to com8=0, 7=1: Transmit repeating FEFI pattern ply with the TP-PMD standard for 100BASE-TX transmis8=1, 7=0: Transmit repeating 1.28 s period squarewave sion over Category-5 unshielded twisted pair cable. There is no ability to bypass this block within the DP83843. 8=1, 7=1: Transmit repeating 160 ns period squarewave 2.2.3 Binary to MLT-3 Convertor / Common Driver O bs Note that these patterns will be routed through the transmit scrambler and become scrambled (and therefore potentially less useful) unless the scrambler is bypassed via bit 12 of LBR (address 17h). It should be noted that if the scrambler is bypassed by forcing the FXEN pin (and subsequently resetting the device) the TPTD+/- outputs will become disabled and the test pattern data will be routed to the FXTD/AUITD+/- outputs. Additionally, the test patterns will not be generated if the DP83843 is in symbol mode. Q D Q The Binary to MLT-3 conversion is accomplished by converting the serial binary datastream output from the NRZI encoder into two binary data streams with alternately phased logic one events. These two binary streams are then fed to the twisted pair output driver which converts these streams to current sources and alternately drives either side of the transmit transformer primary winding resulting in a minimal current (20 mA max) MLT-3 signal. Refer to Figure 4 . binary_in binary_plus binary_minus differential MLT-3 CP binary_plus binary_in COMMON DRIVER MLT-3 binary_minus Figure 1. Binary to MLT-3 conversion 16 www.national.com 2.0 Functional Description (Continued) Table 2. 4B5B Code-Group Encoding/Decoding Name PCS 5B Code-group MII 4B Nibble Code 0 11110 0000 1 01001 0001 2 10100 0010 3 10101 0011 4 01010 0100 5 01011 0101 6 01110 0110 7 01111 0111 8 10010 1000 9 10011 1001 A 10110 10111 11010 D 11011 E 11100 F 1010 1011 1100 1101 1110 ol e B C te DATA CODES 11101 1111 IDLE AND CONTROL CODES H I J K Halt code-group - Error code 11111 Inter-Packet Idle - 0000 (Note 1) 11000 First Start of Packet - 0101 (Note 1) 10001 Second Start of Packet - 0101 (Note 1) 01101 First End of Packet - 0000 (Note 1) bs T 00100 R 00111 Second End of Packet - 0000 (Note 1) V 00000 0110 or 0101 (Note 2) V 00001 0110 or 0101 (Note 2) V 00010 0110 or 0101 (Note 2) V INVALID CODES 0110 or 0101 (Note 2) 00101 0110 or 0101 (Note 2) V 00110 0110 or 0101 (Note 2) V 01000 0110 or 0101 (Note 2) V 01100 0110 or 0101 (Note 2) V 10000 0110 or 0101 (Note 2) V 11001 0110 or 0101 (Note 2) O 00011 V Note 1: Control code-groups I, J, K, T and R in data fields will be mapped as invalid codes, together with RX_ER asserted. Note 2: Normally, invalid codes (V) are mapped to 6h on RXD[3:0] with RX_ER asserted. If the CODE_ERR bit in the PCS (bit 3, register address 16h) is set, the invalid codes are mapped to 5h on RXD[3:0] with RX_ER asserted. Refer to Section 4.14 for further detail. 17 www.national.com 2.0 Functional Description (Continued) such as 100 Mb/s repeaters where data conversion is not always required. The 100BASE-TX MLT-3 signal sourced by the TPTD+/- common driver output pins is slow rate controlled. This should be considered when selecting AC coupling magnetics to ensure TP-PMD compliant transition times (3 ns < Tr < 5ns). 2.3.1 Input and Base Line Wander Compensation Unlike the DP83223V TWISTERTM, the DP83843 requires no external attenuation circuitry at its receive inputs, TPRD+/-. The DP83843 accepts TP-PMD compliant waveforms directly, requiring only a 100 termination plus a simple 1:1 transformer. The DP83843 also requires external capacitance to VCC at the VCM_CAP pin (refer to Figure 23). This establishes a solid common mode voltage that is needed since the TPRD pins are used in both 10 Mb/s and 100 Mb/s modes. The 100BASE-TX transmit TP-PMD function within the DP83843 is capable of sourcing only MLT-3 encoded data. Binary output from the TPTD+/- outputs is not possible in 100 Mb/s mode. 2.2.4 TX_ER 2.2.5 TXAR100 The DP83843 is completely ANSI TP-PMD compliant because it compensates for baseline wander. The BLW compensation block can successfully recover the TP-PMD defined "killer" pattern and pass it to the digital adaptive equalization block. Baseline wander can generally be defined as the change in the average DC content, over time, of an AC coupled digital transmission over a given transmission medium. (i.e. copper wire). te Assertion of the TX_ER input while the TX_EN input is also asserted will cause the DP83843 to substitute HALT codegroups for the 5B data present at TXD[3:0]. However, the SSD (/J/K/) and ESD (/T/R/) will not be substituted with Halt code-groups. As a result, the assertion of TX_ER while TX_EN is asserted will result in a frame properly encapsulated with the /J/K/ and /T/R/ delimiters which contains HALT code-groups in place of the data code-groups. ol e The transmit amplitude of the signal presented at the TPTD+/- output pins can be controlled by varying the value of resistance between TXAR100 and system GND. This Baseline wander results from the interaction between the TXAR100 resistor sets up a reference current that deter- low frequency components of a bit stream being transmitted and the frequency response of the AC coupling compomines the final output current at TPTD+/-. For 100 Category-5 UTP cable implementations, the nent(s) within the transmission system. If the low frequency TXAR100 resistor may be omitted as the DP83843 was content of the digital bit stream goes below the low fredesigned to source a nominal 2V pk-pk differential transmit quency pole of the AC coupling transformers then the amplitude with this pin left floating. Setting the transmit droop characteristics of the transformers will dominate amplitude to 2V pk-pk differential (MLT-3) as measured resulting in potentially serious baseline wander. O bs across the RJ45-8 transmit pins is critical for complying It is interesting to note that the probability of a baseline wanwith the IEEE/ANSI TP-PMD specification of 2.0V pk-pk der event serious enough to corrupt data is very low. In fact, it is reasonable to virtually bound the occurrence of a basedifferential 5%. line wander event serious enough to cause bit errors to a 2.3 100BASE-TX RECEIVER legal but premeditated, artificially constructed bit sequence The 100BASE-TX receiver consists of several functional loaded into the original MAC frame. Several studies have blocks which convert the scrambled MLT-3 125 Mb/s serial been conducted to evaluate the probability of various basedata stream to synchronous 4-bit nibble data that is pro- line wander events for FDDI transmission over copper. Convided to the MII. Because the 100BASE-TX TP-PMD is tact the X3.263 ANSI group for further information. integrated, the differential input pins, TPRD+/-, can be 2.3.2 Signal Detect directly routed to the AC coupling magnetics. The signal detect function of the DP83843 is incorporated See Figure 5 for a block diagram of the 100BASE-TX to meet the specifications mandated by the ANSI FDDI TPreceive function. This provides an overview of each funcPMD Standard as well as the IEEE 802.3 100BASE-TX tional block within the 100BASE-TX receive section. Standard for both voltage thresholds and timing parameThe Receive section consists of the following functional ters. blocks: Note that the reception of Normal 10BASE-T link pulses -- Input and BLW Compensation and fast link pulses per IEEE 802.3u Auto-Negotiation by the 100BASE-X receiver do not cause the DP83843 to -- Signal Detect assert signal detect. -- Digital Adaptive Equalization While signal detect is normally generated and processed -- MLT-3 to Binary Decoder entirely within the DP83843, it can be observed directly on -- Clock Recovery Module the CRS pin (pin 22) while the DP83843 is configured for -- NRZI to NRZ Decoder Symbol mode. Refer to Section 3.4 for further detail regarding Symbol mode operation. -- Serial to Parallel 2.3.3 Digital Adaptive Equalization -- DESCRAMBLER (bypass option) When transmitting data at high speeds over copper twisted -- Code Group Alignment pair cable, frequency dependent attenuation becomes a -- 4B/5B Decoder (bypass option) concern. In high speed twisted pair signalling, the fre-- Link Integrity Monitor quency content of the transmitted signal can vary greatly -- Bad SSD Detection during normal operation based primarily on the randomThe bypass option for the functional blocks within the ness of the scrambled data stream. This variation in signal 100BASE-X receiver provides flexibility for applications 18 www.national.com 2.0 Functional Description (Continued) RX_CLK RXD[3:0] / RX_ER BP_RX MUX BP_4B5B MUX CARRIER INTEGRITY MONITOR SD 4B/5B DECODER LINK INTEGRITY MONITOR RX_DATA VALID SSD DETECT MUX ol e BP_SCR te CODE GROUP ALIGNMENT DESCRAMBLER SERIAL TO PARALLEL CLOCK NRZI TO NRZ DECODER bs DATA O CLOCK RECOVERY MODULE MLT-3 TO BINARY DECODER DIGITAL ADAPTIVE EQUALIZATION INPUT &BLW COMPENSATION SIGNAL DETECT TPRD +/- Figure 1. Receive Block Diagram 19 www.national.com 2.0 Functional Description (Continued) attenuation caused by frequency variations must be compensated for to ensure the integrity of the transmission. In order to ensure quality transmission when employing MLT-3 encoding, the compensation must be able to adapt to various cable lengths and cable types depending on the installed environment. The selection of long cable lengths for a given implementation, requires significant compensation which will over-compensate for shorter, less attenuating lengths. Conversely, the selection of short or intermediate cable lengths requiring less compensation will cause serious under-compensation for longer length cables. Therefore, the compensation or equalization must be adaptive to ensure proper conditioning of the received signal independent of the cable length. 100M 22.00 50M 0M 20.00 18.00 16.00 14.00 12.00 10.00 te 8.00 6.00 4.00 Figure 1. EIA/TIA Attenuation vs Frequency for 0, 50, 100 meters of CAT-5 cable ol e The DP83843 utilizes an extremely robust equalization scheme referred to herein as `Digital Adaptive Equalization.' Existing designs use an adaptive equalization scheme that determines the approximate cable length by monitoring signal attenuation at certain frequencies. This attenuation value was compared to the internal receive input reference voltage. This comparison would indicate that amount of equalization to use. Although this scheme is used successfully on the DP83223V TWISTER, it is sensitive to transformer mismatch, resistor variation and process induced offset. The DP83223V also required an external attenuation network to help match the incoming signal amplitude to the internal reference. tenuation (dB) bs Digital Adaptive Equalization is based on an advanced digitally controlled signal tracking technique. This method uses peak tracking with digital over-sampling and digitally controlled feedback loops to regenerate the receive signal. This technique does not depend on input amplitude variations to set the equalization factor. As a result it maintains constant jitter performance for any cable length up to 150 meters of CAT-5. Digital Adaptive Equalization allows for very high tolerance to signal amplitude variations. The curves given in Figure 6 illustrate attenuation at certain frequencies for given cable lengths. This is derived from the worst case frequency vs. attenuation figures as specified in the EIA/TIA Bulletin TSB-36. These curves indicate the significant variations in signal attenuation that must be compensated for by the receive adaptive equalization circuit. O Figure 7 represents a scrambled IDLE transmitted over zero meters of cable as measured at the AII (Active Input 2ns/div Interface) of the receiver. Figure 8 and Figure 9 represent the signal degradation over 50 and 100 Meters of CAT-5 Figure 2. MLT-3 Signal Measured at AII after 0 meters of cable respectively, also measured at the AII. These plots CAT-5 cable show the extreme degradation of signal integrity and indicate the requirement for a robust adaptive equalizer. 2.3.5 Clock Recovery Module The DP83843 provides the added flexibility of controlling The Clock Recovery Module (CRM) accepts 125 Mb/s the type of receive equalization required for a given imple- NRZI data from the MLT-3 to NRZI decoder. The CRM locks mentation. This is done through TW_EQSEL (bits [13:12] onto the 125 Mb/s data stream and extracts a 125 MHz refof the PHYCTRL register, address 19h). While digital adap- erence clock. The extracted and synchronized clock and tive equalization is the preferred method of cable compen- data are used as required by the synchronous receive sation for 100BASE-TX, the ability to switch the equalizer operations as generally depicted in Figure 5. completely off or to a fixed maximum is provided. This feaThe CRM is implemented using an advanced digital Phase ture is intended as a test mode only and, if enabled, will Locked Loop (PLL) architecture that replaces sensitive inhibit normal performance of the DP83843. analog circuits. Using digital PLL circuitry allows the 2.3.4 MLT-3 to NRZI Decoder DP83843 to be manufactured and specified to tighter tolerThe DP83843 decodes the MLT-3 information from the Dig- ances. ital Adaptive Equalizer block to binary NRZI data. The rela- For further information relating to the 100BASE-X clock tionship of binary to MLT-3 data is shown in Figure 4. recovery module, refer to Section 4.3. 20 www.national.com 2.0 Functional Description (Continued) required function for ultimately providing data to the nibblewide interface of the MII. 2.3.8 Descrambler A 5-bit parallel (code-group wide) descrambler is used to descramble the receive NRZ data. To reverse the data scrambling process, the descrambler has to generate an identical data scrambling sequence (N) in order to recover the original unscrambled data (UD) from the scrambled data (SD) as represented in the equations: SD = ( UD N ) UD = ( SD N ) te Synchronization of the descrambler to the original scrambling sequence (N) is achieved based on the knowledge that the incoming scrambled data stream consists of scrambled IDLE data. After the descrambler has recognized 12 consecutive IDLE code-groups, where an IDLE code-group in 5B NRZ is equal to five consecutive ones (11111), it will synchronize to the receive data stream and generate unscrambled data in the form of unaligned 5B code-groups. 2ns/div In order to maintain synchronization, the descrambler must continuously monitor the validity of the unscrambled data that it generates. To ensure this, a line state monitor and a hold timer are used to constantly monitor the synchronization status. Upon synchronization of the descrambler the hold timer starts a 722 s countdown. Upon detection of sufficient IDLE code-groups within the 722 s period, the hold timer will reset and begin a new countdown. This monitoring operation will continue indefinitely given a properly operating network connection with good signal integrity. If the line state monitor does not recognize sufficient unscrambled IDLE code-groups within the 722 s period, the entire descrambler will be forced out of the current state of synchronization and reset in order to re-acquire synchronization. O bs ol e Figure 1. MLT-3 Signal Measured at AII after 50 meters of CAT-5 cable 2ns/div Figure 2. MLT-3 Signal Measured at AII after 100 meters of CAT-5 cable 2.3.6 NRZI to NRZ In a typical application, the NRZI to NRZ required in order to present NRZ formatted descrambler (or to the code-group alignment descrambler is bypassed, or directly to the receiver is bypassed). The value of the time-out for this timer may be modified from 722 sto 2 ms by setting bit 12 of the PCSR (address 16h) to one. The 2 ms option allows applications with Maximum Transmission Units (packet sizes) larger than IEEE 802.3 specifications to maintain descrambler synchronization (i.e. switch or router applications). Additionally, this timer may be disabled entirely by setting bit 11 of the PCSR (address 16h) to one. The disabling of the time-out timer is not recommended as this will eventually result in a lack of synchronization between the transmit scrambler and the receive descrambler which will corrupt data. The descrambler time-out counter may be reset by bit 13 of the PCSR. 2.3.9 Code-group Alignment decoder is data to the block, if the PCS, if the The code-group alignment module operates on unaligned 5-bit data from the descrambler (or, if the descrambler is bypassed, directly from the NRZI/NRZ decoder) and converts it into 5B code-group data (5 bits). Code-group alignment occurs after the J/K code-group pair is detected. The receive data stream is in NRZI format, therefore, the data Once the J/K code-group pair (11000 10001) is detected, subsequent data is aligned on a fixed boundary. must be decoded to NRZ before further processing. 2.3.10 4B/5B Decoder 2.3.7 Serial to Parallel The 100BASE-X receiver includes a Serial to Parallel converter which supplies 5 bit wide data symbols to the Descrambler. Converting to parallel helps to decrease latency through the device, as well as performing the The code-group decoder functions as a look up table that translates incoming 5B code-groups into 4B nibbles. The code-group decoder first detects the J/K code-group pair preceded by IDLE code-groups and replaces the J/K with 21 www.national.com 2.0 Functional Description (Continued) the MAC preamble. Specifically, the J/K 10-bit code-group pair is replaced by the nibble pair (0101 0101). All subsequent 5B code-groups are converted to the corresponding 4B nibbles for the duration of the entire packet. This conversion ceases upon the detection of the T/R code-group pair denoting the End of Stream Delimiter (ESD) or with the reception of a minimum of two IDLE code-groups. Detection of an unstable link condition will cause bit 4 of the PCS register (address 16h) to be set to one. This bit is cleared to zero upon a read operation once a stable link condition is detected by the CIM. Upon detection of a stable link, the DP83843 will resume normal operations. 2.3.11 100BASE-X Link Integrity Monitor 2.4 10BASE-T TRANSCEIVER MODULE The Disconnect Counter (address 13h) increments each time the CIM determines that the link is unstable. The 100BASE-X Link Integrity Monitor function (LIM) allows the receiver to ensure that reliable data is being received. Without reliable data reception, the LIM will halt both transmit and receive operations until such time that a valid link is detected (i.e. good link). The DP83843 has 2 basic 10BASE-T operational modes: Half Duplex mode Full Duplex mode Half Duplex Mode In Half Duplex mode the DP83843 functions as a standard IEEE 802.3 10BASE-T transceiver supporting the CSMA/CD protocol. ol e -- The descrambler must receive a minimum of 12 IDLE code groups for proper link initialization. -- The Auto-Negotiation must determine that the 100BASE-X function should be enabled. A valid link for a non-Auto-Negotiating application is indicated by either the Link LED output or by reading bit 2 of the Basic Mode Status Register BMSR (address 01h). For a truly qualified valid link indication as a result of AutoNegotiation, bit 2 of the BMSR register (address 01h) must be read. te The 10BASE-T Transceiver Module is IEEE 802.3 compliant. It includes the receiver, transmitter, collision, heartbeat, loopback, jabber, and link integrity functions, as defined in the standard. An external filter is not required on the 10BASE-T interface since this is integrated inside the If Auto-Negotiation is not enabled, then a valid link will be DP83843. Due to the complexity and scope of the indicated once SD+/- is asserted continuously for 500 s. 10BASE-T Transceiver block and various sub-blocks, this If Auto-Negotiation is enabled, then Auto-Negotiation will section focuses on the general system level operation. further qualify a valid link as follows: 2.4.1 Operational Modes Full Duplex Mode In Full Duplex mode the DP83843 is capable of simultaneously transmitting and receiving without asserting the A Bad Start of Stream Delimiter (Bad SSD) is any transition collision signal. The DP83843's 10 Mb/s ENDEC is from consecutive idle code-groups to non-idle code-groups designed to encode and decode simultaneously. which is not prefixed by the code-group pair /J/K. 2.4.2 Oscillator Module Operation If this condition is detected, the DP83843 will assert A 25 MHz crystal or can-oscillator with the following specifiRX_ER and present RXD[3:0] = 1110 to the MII for the cations is recommended for driving the X1 input. cycles that correspond to received 5B code-groups. In order to exit this state the PHYTER must receive at least 1. CMOS output with a 50ppm frequency tolerance. two IDLE code groups and the PHYTER cannot receive a 2. 35-65% duty cycle (max). single IDLE code group at any time. In addition, the False 3. Two TTL load output drive. Carrier Event Counter (address 14h) will be incremented by one. Once the PHYTER exits this state, RX_ER and Additional output drive may be necessary if the oscillator must also drive other components. When using a clock CRS become de-asserted. oscillator it is still recommended that the designer connect When bit 11 of the LBR register is one (BP_RX), RXD[3:0] the oscillator output to the X1 pin and leave X2 floating. and RX_ER/RXD[4] are not modified. 2.4.3 Smart Squelch 2.3.13 Carrier Integrity Monitor The smart squelch is responsible for determining when The Carrier Integrity Monitor function (CIM) protects the valid data is present on the differential receive inputs repeater from transient conditions that would otherwise (TPRD+/-). The DP83843 implements an intelligent cause spurious transmission due to a faulty link. This func- receive squelch to ensure that impulse noise on the receive tion is required for repeater applications and is not speci- inputs will not be mistaken for a valid signal. Smart squelch fied for node applications. operation is independent of the 10BASE-T operational The REPEATER pin (pin 63) determines the default state of mode. bit 5 of the PCS register (Carrier Integrity Monitor Disable, The squelch circuitry employs a combination of amplitude address 16h) to automatically enable or disable the CIM and timing measurements (as specified in the IEEE 802.3 function as required for IEEE 802.3 compliant applications. 10BASE-T standard) to determine the validity of data on After power-up/reset, software may enable or disable this the twisted pair inputs (refer to Figure 10). function independent of Repeater or Node mode. The signal at the start of packet is checked by the smart If the CIM determines that the link is unstable, the squelch and any pulses not exceeding the squelch level DP83843 will not propagate the received data or control (either positive or negative, depending upon polarity) will signaling to the MII and will ignore data transmitted via the be rejected. Once this first squelch level is overcome corMII. The DP83843 will continue to monitor the receive rectly, the opposite squelch level must then be exceeded stream for valid carrier events. within 150 ns. Finally the signal must exceed the original squelch level within a further 150 ns to ensure that the O bs 2.3.12 Bad SSD Detection 22 www.national.com 2.0 Functional Description (Continued) Twisted Pair Squelch Operation <150ns <150ns >150ns Vsq + Vsq + reduced Vsq reduced Vsq start of packet end of packet Figure 1. 10BASE-T Twisted Pair Smart Squelch Operation bs ol e te input waveform will not be rejected. The checking proce- 2.4.5 Normal Link Pulse Detection/Generation dure results in the loss of typically three preamble bits at The link pulse generator produces pulses as defined in the the beginning of each packet. IEEE 802.3 10BASE-T standard. Each link pulse is nomiOnly after all these conditions have been satisfied will a nally 100 ns in duration and is transmitted every 16 ms 8 control signal be generated to indicate to the remainder of ms, in the absence of transmit data. the circuitry that valid data is present. At this time, the Link pulse is used to check the integrity of the connection smart squelch circuitry is reset. with the remote end. If valid link pulses are not received, Valid data is considered to be present until squelch level the link detector disables the 10BASE-T twisted pair transhas not been generated for a time longer than 150ns, indi- mitter, receiver and collision detection functions. cating the End of Packet. Once good data has been When the link integrity function is disabled, the 10BASE-T detected the squelch levels are reduced to minimize the transceiver will operate regardless of the presence of link effect of noise causing premature End of Packet detection. pulses. The receive squelch threshold level can be lowered for use 2.4.6 Jabber Function in longer cable applications. This is achieved by setting the LS_SEL bit in the 10BTSCR (bit 6, register 18h). Collision The jabber function monitors the DP83843's output and disables the transmitter if it attempts to transmit a packet of Detection longer than legal size. A jabber timer monitors the transmitFor Half Duplex, a 10BASE-T collision is detected when the ter and disables the transmission if the transmitter is active receive and transmit channels are active simultaneously. for approximately 20-30 ms. Collisions are reported by the COL signal on the MII. Once disabled by the Jabber function, the transmitter stays If the ENDEC is transmitting when a collision is detected, disabled for the entire time that the ENDEC module's interthe collision is not reported until seven bits have been nal transmit enable is asserted. This signal has to be dereceived while in the collision state. This prevents a colliasserted for approximately 400-600 ms (the "unjab" time) sion being reported incorrectly due to noise on the network. before the Jabber function re-enables the transmit outputs. The COL signal remains set for the duration of the collision. If the ENDEC is receiving when a collision is detected it is The Jabber function is only meaningful in 10BASE-T mode. reported immediately (through the COL). 2.4.7 Status Information O When heartbeat is enabled, approximately 1 s after the transmission of each packet, a Signal Quality Error (SQE) signal of approximately 10 bit times is generated (internally) to indicate successful transmission. SQE is reported as a pulse on the COL signal of the MII. 2.4.4 Carrier Sense Carrier Sense (CRS) may be asserted due to receive activity once valid data is detected via the smart squelch function. For 10 Mb/s Half Duplex operation, CRS is asserted during either packet transmission or reception. 10BASE-T Status Information is available on the LED output pins of the DP83843. Transmit activity, receive activity, link status, link polarity and collision activity information is output to the five LED output pins (LED_RX, LED_TX, LED_LINK, LED_FDPOL, and LED_COL). Additionally, the active high SPEED10 output will assert to indicate 10 Mb/s operation. If required, the LED outputs can be used to provide digital status information to external circuitry. The link LED output indicates good link status for both 10 and 100 Mb/s modes. In Half Duplex 10BASE-T mode, LED_LINK indicates link status. For 10 Mb/s Full Duplex operation, CRS is asserted only The link integrity function can be disabled. When disabled, due to receive activity. the transceiver will operate regardless of the presence of CRS is deasserted following an end of packet. link pulses and the link LED will stay asserted continuously. In Repeater mode, CRS is only asserted due to receive 2.4.8 Automatic Link Polarity Detection activity. The DP83843's 10BASE-T transceiver module incorporates an automatic link polarity detection circuit. When seven consecutive link pulses or three consecutive receive 23 www.national.com 2.0 Functional Description (Continued) packets with inverted End-of-Packet pulses are received, 2.4.12 Manchester Encoder bad polarity is reported. The encoder begins operation when the Transmit Enable A polarity reversal can be caused by a wiring error at either input (TX_EN) goes high and converts the NRZ data to end of the cable, usually at the Main Distribution Frame pre-emphasized Manchester data for the transceiver. For (MDF) or patch panel in the wiring closet. the duration of TX_EN remaining high, the Transmit Data The bad polarity condition is latched and the LED_ FDPOL (TPTD+/-) is encoded for the transmit-driver pair output is asserted. The DP83843's 10BASE-T transceiver (TPTD+/-). TXD must be valid on the rising edge of Transmodule corrects for this error internally and will continue to mit Clock (TX_CLK). Transmission ends when TX_EN decode received data correctly. This eliminates the need to deasserts. The last transition is always positive; it occurs at the center of the bit cell if the last bit is a one, or at the end correct the wiring error immediately. of the bit cell if the last bit is a zero. 2.4.9 10BASE-T Internal Loopback 2.4.13 Manchester Decoder When the 10MB_ENDEC_LB bit in the LBR (bit 4, register address 17h) is set, 10BASE-T transmit data is looped The decoder consists of a differential receiver and a PLL to back in the ENDEC to the receive channel. The transmit separate a Manchester encoded data stream into internal drivers and receive input circuitry are disabled in trans- clock signals and data. The differential input must be exterceiver loopback mode, isolating the transceiver from the nally terminated with either a differential 100ohm termination network to accommodate UTP cable. network. 2.5 100 BASE-FX ol e 2.4.10 Transmit and Receive Filtering The decoder detects the end of a frame when no more midbit transitions are detected. Within one and a half bit times after the last bit, carrier sense is de-asserted. Receive clock stays active for five more bit times after CRS goes low, to guarantee the receive timings of the controller or repeater. te Loopback is used for diagnostic testing of the data path through the transceiver without transmitting on the network or being interrupted by receive traffic. This loopback function causes the data to loopback just prior to the 10BASE-T output driver buffers such that the entire transceiver path is tested. O bs External 10BASE-T filters are not required when using the The DP83843 is fully capable of supporting 100BASE-FX DP83843 as the required signal conditioning is integrated. applications. 100BASE-FX is similar to 100BASE-TX with the exceptions being the PMD sublayer, lack of data scramOnly isolation/step-up transformers and impedance match- bling, and signaling medium and connectors. Chapter 26 of ing resistors are required for the 10BASE-T transmit and the IEEE 802.3u specification defines the interface to this receive interface. The internal transmit filtering ensures PMD sublayer. that all the harmonics in the transmit signal are attenuated The DP83843 can be configured for 100BASE-FX operaby at least 30 dB. tion either through hardware or software. Configuration 2.4.11 Encoder/Decoder (ENDEC) Module through hardware is accomplished by forcing the FXEN pin The ENDEC module consists of essentially four functions: (pin 21) to a logic low level prior to power-up/reset. Configuration through software is accomplished by setting bits 9:7 The oscillator generates the 10 MHz transmit clock signal of the LBR register to <011>, enabling FEFI (bit 14 of regisfor system timing from an external 25 MHz oscillator. ter PCSR(16h)), bypassing the scrambler (bit 12 of register The Manchester encoder accepts NRZ data from the con- LBR(17h)) and disabling Auto-Negotiation. In addition, settroller or repeater, encodes the data to Manchester, and ting the FX_EN bit of the PHYCTRL register (bit 5, address transmits it differentially to the transceiver, through the dif- 19h) accomplishes the same function as forcing the FXEN ferential transmit driver. pin (pin 21) to a logic low. In 100BASE-FX mode, the FX The Manchester decoder receives Manchester data from interface is enabled along with the Far End Fault Indication the transceiver, converts it to NRZ data and recovers clock (FEFI) and Bypass Scrambler functions. Auto-Negotiation pulses for synchronous data transfer to the controller or must be disabled in order for 100BASE-FX operation to work properly. repeater. The collision monitor indicates to the controller the pres- The diagram in Figure 11 is a block diagram representation of the FX interface and the alternative data paths for transence of a valid 10 Mb/s collision signal. mit, receive and signal detect. 24 www.national.com 2.0 Functional Description (Continued) NORMAL RX DATA TO DESCRAMBLER BYPASS NORMAL TX DATA W/ SCRAMBLER BYPASSED NORMAL SIGNAL DETECT CLOCK RECOVERY MODULE NRZ TO NRZI ENCODER PECL INPUTS PECL DRIVER SIGNAL DETECT te INPUT &BLW COMP BINARY TO MLT-3 / COMMON DRIVER FULL ADAPT. EQUALIZ. MLT-3 TO BINARY DEC. TPTD+/- ol e FXTD FXRD FXSD TPRD+/- Figure 1. 100Base-FX Block Diagram tiation is not currently specified for operation over fiber, the Far End Fault Indication function (FEFI) provides some When the FX interface is enabled the internal 100BASE-TX degree of communication between link partners in support transceiver is disabled. As defined by the 802.3u specificaof 100BASE-FX operation. tion, PMD_SIGNAL_indicate (signal detect function), PMD_UNITDATA.indicate (receive function), and A remote fault is an error in the link that one station can PMD_UNIT_DATA.request (transmit function) are sup- detect while the other cannot. An example of this is a disported by the FXSD+/-, FXRD+/-, and FXTD+/- pins connected fiber at a station's transmitter. This station will be receiving valid data and detect that the link is good via respectively. the Link Integrity Monitor, but will not be able to detect that Transmit its transmission is not propagating to the other station. The DP83843 transmits NRZI data on the FXTD+/- pins. A 100BASE-FX station that detects such a remote fault This data is transmitted at PECL signal levels. 100BASE(through the deassertion of signal detect) may modify its FX requires no scrambling/de-scrambling, so the scrambler transmitted IDLE stream from all ones to a group of 84 is bypassed in the transmit path. All other PMA and PCS ones followed by a single zero (i.e. 16 IDLE code groups functions remain unaffected. followed by a single Data 0 code group). This is referred to Receive as the FEFI IDLE pattern. Transmission of the FEFI IDLE The DP83843 receives NRZI data on the FXRD+/- pins. pattern will continue until FXSD+/- is re-asserted. O bs 2.5.1 FX Interface This data is accepted at PECL signal levels. 100BASE-FX requires no scrambling/de-scrambling, so the de-scrambler is bypassed in the receive path. All other PMA and PCS functions remain unaffected. If three or more FEFI IDLE patterns are detected by the DP83843, then bit 4 of the Basic Mode Status register (address 01h) is set to one until read by management. It is also set in bit 7 of the PHY Status register (address 10h). Signal Detect The first FEFI IDLE pattern may contain more than 84 ones The DP83843 receives signal detect information on the as the pattern may have started during a normal IDLE FXSD+/- pins. This data is accepted at PECL signal levels. transmission which is actually quite likely. However, since Signal detect indicates that a signal with the proper ampli- FEFI is a repeating pattern, this will not cause a problem with the FEFI function. It should be noted receipt of the tude is present at the PMD sublayer. FEFI IDLE pattern will not cause CRS to assert. 2.5.2 Far End Fault Indication To enable Fiber mode without FEFI, set bits 9:7 of the LBR Auto-Negotiation provides a mechanism for transferring register to <011>, disable FEFI (bit 14 of register information from the Local Station to the Link Partner that a PCSR(16h)), bypass the scrambler (bit 12 of register remote fault has occurred for 100BASE-TX. As Auto-Nego- 25 www.national.com 2.0 Functional Description (Continued) LBR(17h)) and disable Auto-Negotiation. Without FEFI This function is optional for 100BASE-FX compliance and enabled the DP83843 will not send the FEFI idle pattern. should be disabled for 100BASE-TX compliance. If AutoAdditionally, upon detection of Far End Fault, all receive Negotiation is enabled (bit 12 of the BMCR) then FEFI is and transmit MII activity is disabled/ignored (MII serial automatically disabled. FEFI is automatically enabled when the DP83843 is configured for 100BASE-FX operation. management is unaffected). VCC DP83843 100BASE-FX 82 90 130 82 82 90 9-pin Optical Transceiver 50 FXRD+/- 49 RX_DATA+/- FXSD+/- 48 47 Signal_Detect + RX te TX FXTD+/- 43 44 TX_DATA+/- 370 130 130 115 ol e 130 115 PECL Thevenin Termination Figure 1. Typical DP83843 to Optical Transceiver Interfaces 2.5.3 Software Enable AUI mode is selected by bit 5 (AUI_SEL) of the 10BASE-T Control and Status register (10BTSCR). It can also be activated by the Autoswitch feature explained below. Autoswitch overrides the AUI_SEL bit. The Status of the port, either AUI or TP mode, is displayed in bit 12 (AUI_TPI) of the 10BTSCR register. 2.5.4 FX Interface Considerations 2.6.1 AUI Block Diagram bs The FX functions can also be set via software. The FXinterface is set by bit 5 of the PHYCTRL register (address 19h). The FEFI_EN function is set by bit 14 of register 16h. The bypass scrambler and de-scrambler function is set by bit 11 of the loopback and bypass register (address 17h). O The termination and signal routing for the high-speed The pins at the AUI interface are AUIRD+/-, AUITD+/-, and PECL signals are critical. The following diagram shows a AUICD+/-. They provide the Read, Transmit and Collision Detect functions respectively. See Figure 13 for a block diatypical thevenin termination circuit. gram of the AUI interface. The AUI interface includes the Chapter 26 of the 802.3u 100BASE-X document includes MII Interface/Control references to the three most common types of 125 Mb/s optical transceiver connectors available. The DP83843 may be used with any of these three connectors. tx_data tx_clk crs rx_clk col_ It is important to note that the typical 9-pin low cost fiber detect rx_data transceiver utilizes a single-ended PECL output for Signal Detect indication. Since the DP83843 incorporates stanManchester PLL dard differential PECL inputs for Signal Detect, the FXSDCollision Encoder Decoder input (pin 47) can be externally biased as depicted in Decoder & Driver Figure 12 to ensure proper operation. Optionally, the proper bias potential for FXSD- can be generated by the DP83843 internally. This is accomplished by AUICD+/AUIRD+/AUITD+/setting bit 15 of register 16 (PCSR). This option eliminates the requirement for additional external passive components which would otherwise be required for the proper biasing of Figure 1. AUI Block Diagram FXSD- in an application where only a single-ended SD signal is available. PLL Decoder, Collision Decoder and Manchester Encoder and Driver. 2.6 AUI The DP83843 is capable of operating in 10BASE-2 and 10BASE-5 applications. This is done by utilizing the AUI (Attachment Unit Interface) pins of the DP83843. The AUI interface is completely IEEE 802.3 compliant. See Figure 14 for an example of a typical AUI connector setup. The PLL Decoder receives Manchester data from the transceiver, converts it to NRZ data and clock pulses and sends it to the controller. The collision decoder indicates to the MII the presence of a valid 10 MHz collision signal to the PLL. 26 www.national.com 2.0 Functional Description (Continued) The Manchester encoder accepts NRZ data from the MII, encodes the data to Manchester and sends it to the driver. The driver transmits the data differentially to the transceiver. The DP83843 has an autoswitching feature that allows switching between the AUI and TP operation. The AUI/TPI autoswitch feature (AUTOSW_EN) is enabled by bit 9 of the 10BASE-T Control and Status Register (10BTSCR). If AUTOSW_EN is asserted (default is de-asserted) and the DP83843 is in 10 Mb/s mode it automatically activates the TPI interface (10 Mb/s data is transmitted and received at the TPTD+/- and TPRD+/- pins respectively). If there is an absence of link pulses, the transceiver will switch to AUI mode. Similarly, when the transceiver starts detecting link pulses it will switch to TP mode. The switching from one mode to the next is only done after the current packet has been transmitted or received. If the twisted pair output is jabbering and gets into link fail state, then the switch to AUI mode is only done after the jabbering is done, including the time it takes to unjab (unjab time). 2.6.3 Ethernet Cable Configuration / THIN Output ol e The DP83843 offers the choice of Thick Ethernet (10BASE5) and Thin Ethernet (10BASE-2). The type of cabling used is controlled through bit 3 of the 10BTSCR register (address 18h). The DP83843 also provides a THIN output signal which can be used to disable/enable an external DC-DC converter which is required for 10BASE-2 applications to provide electrical isolation. This enables a 10BASE-2 and10BASE-5 common interface application. AUITD 200 AUIRD AUICD bs 200 te 2.6.2 AUI/TP Autoswitch 100uH 39 39 O 39 .01uf 39 .01uf 15 Pin D AUI Connector Figure 1. AUI Typical Setup 27 www.national.com 3.0 Configuration The Auto-Negotiation function selected at power-up or reset can be changed at any time by writing to the Basic Mode Control Register (BMCR) at address 00h. ol e communicate Auto-Negotiation abilities between two devices at each end of a link segment. For further detail regarding Auto-Negotiation, refer to clause 28 of the IEEE 802.3u specification. The DP83843 supports four different Ethernet protocols (10 Mb/s Half Duplex, 10 Mb/s Full Duplex, 100 Mb/s Half Duplex, and 100 Mb/s Full Duplex), so the inclusion of Auto-Negotiation ensures that the highest performance protocol will be selected based on the ability of the Link Partner. The Auto-Negotiation function within the DP83843 can be controlled either by internal register access or by use of the AN1 and AN0 (pins 3 & 4). te This section includes information on the various configura- Figure 15). These pins allow configuration options to be tion options available with the DP83843. The configuration selected without requiring internal register access. options described herein include: It should be noted that due to the internal resistor networks depicted in Figure 15, the AN0 or AN1 should be con-- Auto-Negotiation nected directly to either VCC or GND, depending on the -- PHY Address and LEDs requirements. These pins should never be resistively tied to -- Half Duplex vs Full Duplex VCC or GND as this will interfere with the internal pull-up -- 100M Symbol mode and pull-down resistors resulting in improper Auto-Negotiation behavior. -- 100BASE-FX mode The state of AN0 and AN1, upon power-up/reset, deter-- 10M serial MII mode mines the state of bit 9 in the PHYSTS register (address -- 10M AUI Mode 10h) as well as bits [8:5] of the ANAR register (address -- Repeater vs. Node 04h). -- Isolate mode Upon power-up/reset the DP83843 uses default register -- Loopback mode values, which enables Auto-Negotiation and advertises the full set of abilities (10 Mb/s Half Duplex, 10 Mb/s Full 3.1 Auto-Negotiation Duplex, 100 Mb/s Half Duplex, and 100 Mb/s Full Duplex) The Auto-Negotiation function provides a mechanism for unless subsequent software accesses modify the mode. exchanging configuration information between two ends of a link segment and automatically selecting the highest per- The status of Auto-Negotiation as a function of hardware formance mode of operation supported by both devices. configuration via the AN0 and AN1 pins is reflected in bit 9 Fast Link Pulse (FLP) Bursts provide the signaling used to of the PHYSTS register (address 10h). 3.1.1 Auto-Negotiation Pin Control bs The state of AN0 and AN1 determines whether the DP83843 is forced into a specific mode or Auto-Negotiation will advertise a specific ability (or set of abilities) as given in Table 3. Pins AN0 and AN1 are implemented as three-level control pins which are configured by connecting them to VCC, GND, or by leaving them unconnected (refer to When Auto-Negotiation is enabled, the DP83843 transmits the abilities programmed into the Auto-Negotiation Advertisement register (ANAR) at address 04h via FLP Bursts. Any combination of 10 Mb/s, 100 Mb/s, Half-Duplex, and Full Duplex modes may be selected. The default setting of bits [8:5] in the ANAR and bit 9 in the PHYSTS register (address 10h) are determined at power-up or hard reset by the state of the AN0 and AN1 pins. The BMCR provides software with a mechanism to control the operation of the DP83843. However, the AN0 and AN1 pins do not affect the contents of the BMCR and cannot be used by software to obtain status of the mode selected.Bits 1 & 2 of the PHYSTS register (address 10h) are only valid if Auto-Negotiation is disabled or after Auto-Negotiation is complete. VH - R A + VIN - R B DECODER O VCC 3.1.2 Auto-Negotiation Register Control OUT VIN A B OUT 0V L L L VCC /2 L H M VCC H H H + VL GND Figure 15. 3 Level Hardware Configuration Pin Control The contents of the ANLPAR register are used to automatically configure to the highest performance protocol between the local and far-end ports. Software can determine which mode has been configured by Auto-Negotiation by comparing the contents of the ANAR and ANLPAR registers and then selecting the technology whose bit is set in both the ANAR and ANLPAR of highest priority relative to the following list. 28 www.national.com 3.0 Configuration (Continued) Table 3. Auto-Negotiation Mode Select AN1 (Pin 3) AN0 (Pin 4) Action Mode FORCED MODES 0 M PHYSTS (10h) Bit 9 = 0, Bit 1 = 1, Bit 2 = 0 10BASE-T, Half-Duplex without Auto-Negotiation ANAR (04h) [8:0] = 021h 1 M PHYSTS (10h) Bit 9 = 0, Bit 1 = 1, Bit 2 = 1 10BASE-T, Full Duplex without Auto-Negotiation ANAR (04h) [8:0] = 041h M 0 M 1 PHYSTS (10h) Bit 9 = 0, Bit 1 = 0, Bit 2 = 0 ANAR (04h) [8:0] = 081h PHYSTS (10h) Bit 9 = 0, Bit1 = 0, Bit 2 = 1 ANAR (04h) [8:0] = 101h 100BASE-X, Half-Duplex without Auto-Negotiation 100BASE-X, Full Duplex without Auto-Negotiation ADVERTISED MODES M PHYSTS (10h) Bit 9 = 1 ANAR (04h) [8:0] = 1E1h 0 0 0 1 PHYSTS (10h) Bit 9 = 1 ANAR (04h) [8:0] = 061h 10BASE-T, Half-Duplex & Full Duplex advertised via Auto-Negotiation 100BASE-TX, Half-Duplex & Full Duplex advertised via Auto-Negotiation ol e PHYSTS (10h) Bit 9 = 1 All capable (i.e. Half-Duplex & Full Duplex for 10BASE-T and 100BASE-TX) advertised via Auto-Negotiation te M ANAR (04h) [8:0] = 181h 1 0 PHYSTS (10h) Bit 9 = 1 10BASE-T & 100BASE-TX, Half-Duplex advertised via Auto-Negotiation ANAR (04h) [8:0] = 0A1h 1 1 PHYSTS (10h) Bit 9 = 1 10 BASE-T, Half-Duplex advertised via Auto-Negotiation. ANAR (04h) [8:0] = 021h Note: "M" indicates logic mid level (Vcc/2), "1" indicates logic high level, "0" indicates logic low level. Auto-Negotiation Priority Resolution: -- Whether the Link Partner is advertising that a remote fault has occurred (bit 4, register address 01h) -- Whether a valid link has been established (bit 2, register address 01h) -- Support for Management Frame Preamble suppression (bit 6, register address 01h) The Auto-Negotiation Advertisement Register (ANAR) at address 04h indicates the Auto-Negotiation abilities to be advertised by the DP83843. All available abilities are transmitted by default, but any ability can be suppressed by writing to the ANAR. Updating the ANAR to suppress an ability is one way for a management agent to change (force) the technology that is used. O bs -- (1) 100BASE-TX Full Duplex (Highest Priority) -- (2) 100BASE-TX Half Duplex -- (3) 10BASE-T Full Duplex -- (4) 10BASE-T Half Duplex (Lowest Priority) The Basic Mode Control Register (BMCR) at address 00h provides control of enabling, disabling, and restarting of the Auto-Negotiation function. When Auto-Negotiation is disabled the Speed Selection bit in the BMCR (bit 13, register address 00h) controls switching between 10 Mb/s or 100 Mb/s operation, while the Duplex Mode bit (bit 8, register address 00h) controls switching between full duplex operation and half duplex operation. The Speed Selection and Duplex Mode bits have no effect on the mode of operation The Auto-Negotiation Link Partner Ability Register when the Auto-Negotiation Enable bit (bit 12, register (ANLPAR)at address 05h is used to receive the base link code word as well as all next page code words during the address 00h) is set. negotiation. Furthermore, the ANLPAR will be updated to The Basic Mode Status Register (BMSR) at address 01h either 0081h or 0021h for parallel detection to either 100 indicates the set of available abilities for technology types Mb/s or 10 Mb/s respectively. (bits 15 to 11, register address 01h), Auto-Negotiation ability (bit 3, register address 01h), and Extended Register If Next Page is NOT being used, then the ANLPAR will Capability (bit 0, register address 01h). These bits are per- store the base link code word (link partner's abilities) and manently set to indicate the full functionality of the retain this information from the time the page is received, DP83843 (only the 100BASE-T4 bit is not set since the as indicated by a 1 in bit 1 of the Auto-Negotiation ExpanDP83843 does not support that function, while it does sup- sion Register (ANER, register address 06h), through the end of the negotiation and beyond. port all the other functions). When using the next page operation, the DP83843 cannot The BMSR also provides status on: wait for Auto-Negotiation to complete in order to read the -- Whether Auto-Negotiation is complete (bit 5, register ad- ANLPAR because the register is used to store both the dress 01h) 29 www.national.com 3.0 Configuration (Continued) ner. Note that bits 4:0 of the ANLPAR will also be set to 00001 based on a successful parallel detection to indicate a valid 802.3 selector field. Software may determine that negotiation completed via Parallel Detection by reading a zero in the Link Partner Auto-Negotiation Able bit (bit 0, register address 06h) once the Auto-Negotiation Complete bit (bit 5, register address 01h) is set. If configured for parallel detect mode and any condition other than a single good link occurs then the parallel detect fault bit will set (bit 4, register 06h). base and next pages. Software must be available to perform several functions. The ANER (register 6) must have a page received (bit 1), once the DP83843 receives the first page, software must store it in memory if it wants to keep the information. Auto-Negotiation keeps a copy of the base page information but it is no longer accessible by software. After reading the base page information, software needs to write to ANNPTR (register 7) to load the next page information to be sent. Continue to poll the page received bit in the ANER and when active read the ANLPAR. The contents of the ANLPAR will tell if the partner has further pages to be sent. As long as the partner has more pages to send, software must write to the next page transmit register and load another page. 3.1.4 Auto-Negotiation Restart O bs ol e te Once Auto-Negotiation has completed, it may be restarted at any time by setting bit 9 of the BMCR to one. If the mode configured by a successful Auto-Negotiation loses a valid The Auto-Negotiation Expansion Register (ANER) at link, then the Auto-Negotiation process will resume and address 06h indicates additional Auto-Negotiation status. attempt to determine the configuration for the link. This The ANER provides status on: function ensures that a valid configuration is maintained if -- Whether a Parallel Detect Fault has occurred (bit 4, reg- the cable becomes disconnected. ister address 06h) A renegotiation request from any entity, such as a manage-- Whether the Link Partner supports the Next Page func- ment agent, will cause the DP83843 to halt any transmit tion (bit 3, register address 06h) data and link pulse activity until the break_link_timer -- Whether the DP83843 supports the Next Page function expires (~1500ms). Consequently, the Link Partner will go (bit 2, register address 06h). The DP83843 does support into link fail and normal Auto-Negotiation resumes. The DP83843 will resume Auto-Negotiation after the the Next Page function. break_link_timer has expired by issuing FLP (Fast Link -- Whether the current page being exchanged by Auto-NePulse) bursts. gotiation has been received (bit1, register address 06h) -- Whether the Link Partner supports Auto-Negotiation (bit 3.1.5 Enabling Auto-Negotiation via Software 0, register address 06h) It is important to note that if the DP83843 has been initialThe Auto-Negotiation Next Page Transmit Register ized upon power-up as a non-auto-negotiating device (ANNPTR) at address 07h contains the next page code (forced technology), and it is then required that Auto-Negoword to be sent. See Table 13 for a bit description of this tiation or re-Auto-Negotiation be initiated via software, bit 12 of the Basic Mode Control Register (address 00h) must register. first be cleared and then set for any Auto-Negotiation func3.1.3 Auto-Negotiation Parallel Detection tion to take effect. The DP83843 supports the Parallel Detection function as 3.1.6 Auto-Negotiation Complete Time defined in the IEEE 802.3u specification. Parallel Detection requires both the 10 Mb/s and 100 Mb/s receivers to moni- Parallel detection and Auto-Negotiation take approximately tor the receive signal and report link status to the Auto- 2-3 seconds to complete. In addition, Auto-Negotiation with Negotiation function. Auto-Negotiation uses this informa- next page should take approximately 2-3 seconds to comtion to configure the correct technology in the event that the plete, depending on the number of next pages sent. Link Partner does not support Auto-Negotiation yet is Refer to chapter 28 of the IEEE 802.3u standard for a full transmitting link signals that the 100BASE-X or 10BASE-T description of the individual timers related to Auto-NegotiaPMAs recognize as valid link signals. tion. The Auto-Negotiation function will only accept a valid link Auto-Negotiation Next Page Support signal for the purpose of Parallel Detection from PMAs which have a corresponding bit set in the Auto-Negotiation The DP83843 supports the optional Auto-Negotiation Next Advertisement register, (ANAR register bits 5 and 7, Page protocol. The ANNPTR register (address 07h) allows address 04h.) This allows the DP83843 to be configured for the configuration and transmission of Next Page. Refer for 100 Mb/s only, 10 Mb/s only, or 10 Mb/s & 100 Mb/s to clause 28 of the IEEE 802.3u standard for detailed inforCSMA/CD operation depending on the advertised abilities. mation regarding the Auto-Negotiation Next Page function. The state of these bits may be modified via the AN0 and 3.2 PHY Address and LEDs AN1 pins or by writing to the ANAR. For example, if bit 5 is zero, and bit 7 is one in the ANAR (i.e. 100 Mb/s CSMA/CD The DP83843 maps the 5 PHY address input pins onto the only), and the Link Partner is 10BASE-T without Auto- 5 LED output pins as: LED_COL <=> PHYAD[0] Negotiation, then Auto-Negotiation will not complete since the advertised abilities and the detected abilities have no LED_TX <=> PHYAD[1] common mode. This operation allows the DP83843 to be LED_RX <=> PHYAD[2] used in single mode (i.e. repeater) applications as well as LED_LINK <=> PHYAD[3] dual mode applications (i.e. 10/100 nodes or switches). LED_FDPOL <=> PHYAD[4] If the DP83843 completes Auto-Negotiation as a result of Parallel Detection, without Next Page operation, bits 5 and The DP83843 can be set to respond to any of 32 possible 7 within the ANLPAR register (register address 05h) will be PHY addresses. Each DP83843 connected to a common set to reflect the mode of operation present in the Link Part- serial MII must have a unique address. It should be noted 30 www.national.com 3.0 Configuration (Continued) that while an address selection of all zeros <00000> will The adaptive nature of the LED outputs helps to simplify result in PHY Isolate mode, this will not effect serial man- potential implementation issues of these dual purpose pins. agement access. The state of each of the PHYAD inputs are latched into the PHYCTRL register bits [4:0] (address 19h) at system power-up/reset depending on whether a pull-up or pulldown resistor has been installed for each pin. For further detail relating to the latch-in timing requirements of the PHY Address pins, as well as the other hardware configuration pins, refer to the Reset summary in Section 5. Refer to the PHYCTRL register (address 19h) bits [8:6] for further information regarding LED operations and configuration. Since the PHYAD strap options share the LED output pins, the external components required for strapping and LED usage must be considered in order to avoid contention. Additionally, the sensing and auto polarity feature of the LED must be taken into account. Half-duplex is the standard, traditional mode of operation which relies on the CSMA/CD protocol to handle collisions and network access. In Half-Duplex mode, CRS responds to both transmit and receive activity in order to maintain compliant to the IEEE 802.3 specification. Specifically, these LED outputs can be used to drive LEDs directly, or can be used to provide status information to a network management device. The active state of each LED output driver is dependent on the logic level sampled by the corresponding PHYAD input upon power-up / reset. For example, if a given PHYAD input is resistively pulled low (nominal 10 k resistor recommended) then the corresponding LED output will be configured as an active high driver. Conversely, if a given PHYAD input is resistively pulled high, then the corresponding LED output will be configured as an active low driver. Refer to Figure 16 for an example of LED & PHYAD connection to external components where, in this example, the PHYAD strapping results in address 00011 or hex 03h or decimal 3. Since the DP83843 is architected to support simultaneous transmit and receive activity it is capable of supporting fullduplex switched applications with an aggregate throughput of up to 200 Mb/s when operating in 100BASE-X mode. Because the CSMA/CD protocol does not apply to fullduplex operation, the DP83843 simply disables its own internal collision sensing and reporting functions and modifies the behavior of Carrier Sense (CRS) such that it indicates only receive activity to allow the full-duplex capable MAC to operate properly. 3.3 Half Duplex vs. Full Duplex VCC 1 10 LED_TX/PHYAD[1] 1 10 1 10 1 10 bs 1 10 O LED_COL/PHYAD[0] All modes of operation (100BASE-TX, 100BASE-FX, 10BASE-T (both nibble and serial)) can run full-duplex although it should be noted that full-duplex operation does not apply to typical repeater implementations or AUI applications. Additionally, other than CRS and Collision reporting, all remaining MII signaling remains the same regardless of the selected duplex mode. LED_RX/PHYAD[2] LED_LINK/PHYAD[3] LED_FDPOL/PHYAD[4] ol e te The DP83843 supports both half and full duplex operation at both 10 Mb/s and 100 Mb/s speeds. VCC Figure 16. PHYAD Strapping and LED Loading Example 31 www.national.com 3.0 Configuration (Continued) Please refer to Section 2.2 for more information regarding 100BASE-FX operation. It is important to understand that while full Auto-Negotiation with the use of Fast Link Pulse code words can interpret and configure to support full-duplex, parallel detection can not recognize the difference between full and half-duplex from a fixed 10 Mb/s or 100 Mb/s link partner over twisted pair. Therefore, as specified in 802.3u, if a far-end link partner is transmitting forced full duplex 100BASE-TX for example, the parallel detection state machine in the receiving station would be unable to detect the full duplex capability of the far-end link partner and would negotiate to a half duplex 100BASE-TX configuration (same scenario for 10 Mb/s). 3.6 10 Mb/s Serial Mode The DP83843 allows for serial MII operation. In this mode, the transmit and receive MII data transactions occur serially at a 10 MHz clock rate on the least significant bits (RXD[0] and TXD[0]) of the MII data pins. This mode is intended for use with a MAC based on a 10 Mb/s serial interface. While the MII control signals (CRS, RX_DV, TX_DV, and TX_EN) as well as RX_EN and Collision are still used during 10 Mb/s Serial mode, some of the timing parameters are different. Refer to Section 8 for AC timing details. 3.4 100 Mb/s Symbol Mode Similarly, the TX_ER input pin is configured as the new MSB (TXD[4]) to support the unaligned 5 bit transmit data. Both 10BASE-T and AUI can be configured for Serial mode. Serial mode is not supported for 100 Mb/s operation. Serial mode can be selected via hardware by forcing the SERIAL10 pin (pin 69) to a logic low level prior to powerup/reset. The state of the SERIAL10 pin is latched into bits 11 and 12 of the 10BTSCR register (address 18h) as a result of power-up/reset. These bits can be written through software to control serial mode operation. te In Symbol mode, all of the conditioning blocks in the transmit and receive sections of the 100BASE-X section are bypassed. The 100BASE-X serial data received at the RD+/- inputs of the DP83843 are recovered by the integrated PMD receiver, shifted into 5-bit parallel words and presented to the MII receive outputs RXD[3:0] and RX_ER/RXD[4]. All data, including Idles, passes through the DP83843 unaltered other than for serial/parallel conversions. ol e While in 10 Mb/s serial mode, RXD[3:1] will be placed in All data, including Idles, passes through the DP83843 unal- TRI-STATE mode and RX_DV asserts coincident with CRS. tered other than for serial/parallel conversions. 3.7 10 Mb/s AUI Mode While in Symbol mode RX_DV and COL are held low and TX_ER is used as the fifth bit and no longer functions as TX_ER. Additionally, the CRS output reports the state of signal detect as generated internally for 100BASE-TX and externally for 100BASE-FX. O bs Placing the DP83843 in AUI mode enables the FXTD/AUITD, FXRD/AUIRD, and FXSD/CD pin pairs to allow for any AUI compliant external transceivers to be connected to the AUI interface. Placing the DP83843 in 10 Mb/s AUI mode disables the TPTD and TPRD transmit and Symbol mode can be used for those applications where the receive pin pairs. system design requires only the integrated PMD, clock The DP83843 also incorporates a THIN output control pin recovery, and clock generation functions of the DP83843. for use with traditional AUI based CTI transceivers. This This is accomplished either by configuring the CRS/SYM- output follows the state of bit 3 in the 10BTSCR register BOL pin (pin 22) of the DP83843 to a logic low level prior to accessible through the serial MII. power-up/reset or by setting bits 10 and 11 (BP_TX and BP_RX respectively) of the LBR register (address 17h) The AUI/TP autoswitching allows transceiver autoswitching through the serial MII port. Symbol mode only applies to between the AUI and TP outputs. At power up, the autoswitch function is deselected in the 10BTSCR register 100BASE-X operation. (bit 9 = 0) and the current mode, AUI or TP, is reported by 3.5 100BASE-FX Mode the bit 13 of the 10BTSCR register (low for TPI and high for The DP83843 will allow 100BASE-FX functionality by AUI). bypassing the scrambler and descrambler and routing the When the auto-switch function is enabled (bit 9 = 1), it PECL serial transmit and receive data through the separate allows the transceiver to automatically switch between TPI FXTD/AUITD outputs and FXRD/AUIRD inputs respec- and AUI I/O's. If there is an absence of link pulses, the tively. Additionally, the signal detect indication from the opti- transceiver switches to AUI mode. Similarly, when the cal transceiver is handled by the FXSD inputs. Placing the transceiver starts detecting link pulses, it switches to TP DP83843 in 100BASE-FX mode disables the TPTD and mode. Switching from one mode to the other is done only TPRD transmit and receive pin pairs. after the current packet has been transmitted or received. If Configuring the DP83843 for 100BASE-FX mode can be the twisted pair output is jabbering and it gets into link fail accomplished either through hardware configuration or via state, then the switch to AUI mode is done only after the jabbering has stopped, including the time it takes to unjab software. (unjab time). Also, if TPI mode is selected, transmit packet The hardware configuration is set simply by tying the data are driven only by the TPI outputs and the AUI transCOL/FXEN pin (21) to a logic low level prior to power- mit outputs remain idle. Similar behavior applies when AUI on/reset. The software setting is accomplished by setting mode is selected. The only difference in AUI mode is that the BP_SCR bit (bit 12) of the LBR register (address 17h) the TP drivers continue to send link pulses; however, no via MII serial management. packet data is transmitted. The TPI receive circuitry and The DP83843 can support either half-duplex or full-duplex the Link Integrity state machine are always active to enable operation while in 100BASE-FX mode. Additionally, all MII this algorithm to function as described above. signaling remains identical to that of 100BASE-TX operation. 32 www.national.com 3.0 Configuration (Continued) 3.8 Repeater vs. Node diagnostic, this mode serves as quick functional verification of the device. The DP83843 Carrier Sense (CRS) operation depends on the value of the Repeater bit in the PHYCTRL register (bit 9, address 19h). When set high, the CRS output (pin 22) is asserted for receive activity only. When set low, the CRS output is asserted for either receive or transmit activity. The default value for this bit is set by the THIN/REPEATER pin (pin 63) at power-up/reset. In addition to Loopback mode, there are many other test modes that serve similar loopback functions. These modes are mutually exclusive with Loopback mode, enabling Loopback mode disables the following test modes: There is an internal pullup resistor for this pin which is active during the power-up/reset period. If this pin is left floating externally, then the device will configure to Repeater mode as a result of power-up/reset. This pin must be externally pulled low (typically 10 k) in order to configure the DP83843 for node operation. First, CRS will only respond to receive activity. Second, in compliance with the 802.3 standard, the Carrier Integrity Monitor (CIM) function is automatically enabled for detection and reporting of bad start of stream delimiters (whereas in node mode the CIM is disabled). 3.9 Isolate Mode ol e The Dp83843 does not support 10Mb/s repeater applications. te When the repeater mode of operation is selected during 100 Mb/s operation, there are two parameters that are directly effected. -- CP_Loop (bits 9:7) of the Loopback and Bypass Register (LBR). These bits control the 100 Mb/s loopback functions in more depth. A write of either a 0 or 1 to `Loopback' causes these bits to be set to <000> which is normal operation. At reset if FXEN is true then this will default to, <011> which is Normal Fiber operation, otherwise it will default to <000>. The other modes are explained in the LBR definition table. -- Dig_Loop (bit 6) of the LBR. Digital loopback is used to place the digital portions of the DP83843 into loopback prior to the signals entering the analog sections. A write of either a 0 or 1 to `Loopback' causes this bits to be set to 0 which is digital loopback disabled. Bit 5 and Bit 4 of the LBR are automatically enabled in Loopback mode. They are TWISTER (100 Mb/s) loopback and TREX (10 Mb/s) loopback modes respectively. bs An IEEE 802.3u compliant PHY connected to the mechanical MII interface is required to have a default value of one in bit 10 of the Basic Mode Control Register (BMCR, address 00h.) The DP83843 will set this bit to one if the PHY Address is set to 00000 upon power-up/hardware reset. Otherwise, the DP83843 will set this bit to zero upon power-up/hardware reset. Refer to Section 2.4.2 for information relating to the requirements for selecting a given PHYAD. With bit 10 in the BMCR set to one the DP83843 does not respond to packet data present at TXD[3:0], TX_EN, and TX_ER inputs and presents a high impedance on the TX_CLK, RX_CLK, RX_DV, RX_ER, RXD[3:0], COL, and CRS outputs. The DP83843 will continue to respond to all management transactions. O While in Isolate mode, the TD+/- outputs will not transmit packet data but will continue to source 100BASE-TX scrambled idles or 10BASE-T normal link pulses. 3.10 Loopback The DP83843 includes a Loopback Test mode for easy board diagnostics. The Loopback mode is selected through bit 14 (`Loopback') of the Basic Mode Control Register (BMCR). The status of this mode may be checked in bit 3 of the PHY Status Register. Writing 1 to this bit enables MII transmit data to be routed to the MII receive outputs. In Loopback mode the data will not be transmitted on to the media. This occurs for either 10 Mb/s or 100 Mb/s data. Normal 10BASE-T, 10BASE-2, or 10BASE-5 operation, in order to be standard compliant, also loops back the MII transmit data to the MII receive data. However the data is also allowed to be transmitted out the AUI or TP ports (depending on the mode). In 100 Mb/s Loopback mode the data is routed through the PCS and PMA layers into the PMD sublayer before it is looped back. Therefore, in addition to serving as a board 33 www.national.com 4.0 Clock Architecture serves to clock out the 125Mb/s serial bit stream for 100BASE-TX and 100BASE-FX applications. The 125 MHz clock is also routed to a counter where it is divided by 5 to produce the 25 MHz TX_CLK signal for the transmit MII. Additionally, a set of phase related 250 MHz clock signals are routed to the Clock Recovery Module (CRM) The DP83843 also incorporates Clock Recovery circuitry which act as a frequency reference to ensure proper opera(CRM) which extracts the 125 MHz clock from the 125 tion. Mb/s receive datastream present during 100BASE-TX and For 10 Mb/s operation, the external 25 MHz reference is routed to a 100 MHz voltage controlled oscillator. The high 100BASE-FX applications (Figure 17). The 10 Mb/s receive clock requirements are handled by a frequency output from the oscillator is divided by five and PLL which is tuned to extract a clock from either 10BASE-T serves to clock out the 10BASE-T or AUI serial bit stream or AUI receive Manchester encoded data streams for 10 Mb/s applications. The 100 MHz clock is also routed to a counter where it is divided by either eight or two to pro(Figure 17). duce the 2.5 MHz or 10 MHz TX_CLK signal for the trans4.1 Clock Generation Module (CGM) mit MII. Additionally, a set of phase related 100 MHz clock For 100 Mb/s operation, the external 25 MHz reference is signals are routed to the Clock Recovery Module (CRM) routed to a 250 MHz voltage controlled oscillator. The high which act as a frequency reference to ensure proper operafrequency output from the oscillator is divided by two and tion. te The DP83843 incorporates a sophisticated Clock Generation Module (CGM) design which allows full operation supporting all modes with a single 25 MHz ( 50 ppm) CMOS level reference clock. As depicted in Figure 17, the single 25 MHz reference serves both the 100 Mb/s and 10 Mb/s mode clocking requirements. 100M CLOCKING ol e Ref Clock to CRM Divide by 5 VCO (250 MHz) bs 25 MHz Divide by 2 25 MHz MII TX_CLK 125 MHz serial transmit clock input O VCO (100 MHz) 10M CLOCKING 20 MHz 10BASE-T transmit clock Divide by 5 Divide by 8 or 2 2.5 MHz or 10 MHz MII TX_CLK Ref Clock to CRM Figure 17. Clock Generation Module BLOCK DIAGRAM 34 www.national.com 4.0 Clock Architecture (Continued) 125Mb/s Serial Data Input Phase Detector Phase Error Processor Deserializer RXD [4:0] Digital Loop Filter 25 MHz RX_CLK te Divide by 2 Frequency Reference From CGM ol e Phase to Frequency Converter Frequency Controlled Oscillator bs Figure 18. 100BASE-X Clock Recovery Module block diagram Phase Detector & CRS Filter O 10 Mb/s Serial Data Input CRS Phase Selector Clk Gen Serial / Nibble MUX Frequency Reference From CGM 10 MHz RX_CLK RXD[0] Serial Data Deserializer RXD[3:0] 2.5 MHz RX_CLK Figure 19. 10M Manchester Clock Recovery Module block diagram 35 www.national.com 4.0 Clock Architecture (Continued) 4.2 100BASE-X Clock Recovery Module 10BASE-T or AUI inputs, is routed to the input of the phase detector. A loop consisting of the phase detector, digital loop filter, phase selector, and the frequency generator then works to synthesize a 20 MHz clock based on the receive data stream. This clock is used to latch the serial data into the deserializer where the data is then optionally converted to 4-bit code groups for presentation to the MII as nibble wide data clocked out at 2.5 MHz. Optionally, the deserializer can be bypassed and the 10 Mb/s data is clocked out serially at 10 MHz. The diagram in Figure 18 illustrates a high level block architecture of the 100BASE-X Clock Recovery circuit. The 125Mb/s serial binary receive data stream that has been recovered by the integrated TP-PMD receiver is routed to the input of the phase detector. A loop consisting of the phase detector, phase error processor, digital loop filter, phase to frequency converter, and the frequency controlled oscillator then works to synthesize a 125 MHz clock based on the receive data stream. This clock is used to latch the serial data into the deserializer where the data is then converted to 5-bit code groups for processing by descrambler, code-group alignment, and code-group decoder functional blocks. As a function of the Phase Detector, upon recognizing an incoming 10 Mb/s datastream, Carrier Sense (CRS) is generated for use by the MAC. 4.4 Reference Clock Connection Options 4.3 10 Mb/s Clock Recovery Module ol e te The two basic options for connecting the DP83843 to an The diagram in Figure 19 illustrates a high level block archi- external reference clock consist of the use of either an tecture of the 10 Mb/s Clock Recovery circuit. The 10 Mb/s oscillator or a crystal. Figure 20 and 21 illustrate the recserial Manchester receive data stream, from either the ommended connection for the two typical options. 25 MHz Osc 50ppm X1 X2 n/c bs Figure 20. Oscillator Reference Clock Connection Diagram O 33pF X1 X2 33pF 25 MHz Xtal 50ppm Figure 21. Xtal Reference Clock Connection Diagram 36 www.national.com 5.0 Reset Operation Table 4. Latched pins at Reset The DP83843 can be reset either by hardware or software. A hardware reset may be accomplished either by asserting the RESET pin during normal operation, or upon powering up the device. A software reset is accomplished by setting the reset bit in the Basic Mode Control Register. Pin # While either the hardware or software reset can be implemented at any time after device initialization, providing a hardware reset, as described in Section 6.2 must be implemented upon device power-up/initialization. Omitting the hardware reset operation during the device power-up/initialization sequence can result in improper device operation. Depending on the crystal starting up time, it is recommended to wait 20 ms after the supply has reached its proper value before initiating a hardware reset. Primary Function Latched in at Reset 21 COL FXEN 22 CRS SYMBOL 38 LED_FDPOL PHYAD4 39 LED_LINK PHYAD3 40 LED_RX PHYAD2 41 LED_TX PHYAD1 42 LED_COL PHYAD0 63 THIN REPEATER 69 SERIAL10 SERIAL10 5.1 Power-up / Reset te 5.3 Software Reset A software reset is accomplished by setting the reset bit (bit 15) of the Basic Mode Control register (address 00h). This bit is self clearing and, when set, will return a value of "1" until the software reset operation has completed. The period from the point in time when the reset bit is set to the point in time when software reset has concluded is approximately 5 s. ol e When VCC is first applied to the DP83843 it takes some amount of time for power to actually reach the nominal 5V potential. This initial power-up time can be referred to as a VCC ramp when VCC is "ramping" from 0V to 5V. When the initial VCC ramp reaches approximately 4V, the DP83843 begins an internal reset operation which must be allowed sufficient time, relative to the assertion and deassertion of the RESET pin, to reset the device. There are two methods for guaranteeing successful reset upon device power-up. The first method accounts for those designs that utilize a special power up circuit which, through hardware, will assert the RESET pin upon power-up. In this case, the deassertion (falling edge) of the RESET pin must not occur until at least 500 s after the time at which the VCC ramp initially reached the 4V point. The software reset will reset the device such that all registers will be reset to default values and the hardware configuration values will be re-latched into the device (similar to the power-up/reset operation). Driver code should wait 500 s following a software reset before allowing further serial MII operations with the DP83843. bs The second method accounts for those applications which produce a reset pulse sometime after the initial power-up of the device. In this case, it is recommended that a positive pulse, with a duration of at least 1 s, be applied to the RESET pin no sooner than 500 s after the point in time where the initial VCC ramp reached 4V. O In both methods described above, it is important to note that the logic levels present at each of the hardware configuration pins of the DP83843 (see list below) are also latched into the device as a function of the reset operation (either hardware or software). These hardware configuration values are guaranteed to be latched into the DP83843 2 s after the deassertion of the RESET pin. The hardware configuration values latched into the DP83843 during the reset operation are dependent on the logic levels present at the device pins shown in Table 4 upon power-up. During the power-up/ reset operation the LED1 through LED5 pins are undefined, the SPEED10 will be asserted. The 25 MHz clock reference must be applied for reset to take effect. 5.2 Hardware Reset A hardware reset is accomplished by applying a positive pulse (TTL level), with a duration of at least 1 s, to the RESET pin of the DP83843 during normal operation. This will reset the device such that all registers will be reset to default values and the hardware configuration values will be re-latched into the device (similar to the power-up/reset operation). 37 www.national.com 6.0 DP83843 Application 6.1 Typical Node Application 6.2 Power And Ground Filtering Figure 22 illustrates a typical implementation of a 10/100 Mb/s node application. This is given only to indicate the major circuit elements of such a design. It is not intended to be a full circuit diagram. For detailed system level application information please contact your local National sales representative. Sufficient filtering between the DP83843 power and ground pins placed as near to these pins as possible is recommended. Figure 23 suggests one option for device noise filtering including special consideration for the sensitive analog power pins. This cap is an optional component for control of transmit transition time. An inital value of 10pF is suggested. TBD 49.9 49.9 100pF 3kV 49.9 DP83843 { (73) TPTD- --TX- Optional 10pF Cap connected to the center tap of the transmit transformer TX_CLK (33) GND (67) TPRD+ MDC (35) MDIO (34) Management --TX+ te Transmit MII RJ45-8 GND (74) TPTD+ TX_EN (25) TXD0 (31) TXD1 (30) TXD2 (29) TXD3 (28) TX_ER (24) VDD --RX+ (65) TPRDRXD0 (15) RXD1 (14) RXD2 (13) RXD3 (12) RX_ER (19) RX_DV (20) RX_CLK (18) Receive MII ol e { 1.5K --RX- (66) VCM_CAP 49.9 49.9 100pF 3kV 49.9 GND Optional 10pF Cap connected to the center tap of the receive transformer GND RX_EN (23) (78) TXAR100 10K NC (50) FXRD+/AUIRD+ NC NC CRS/SYMBOL (22) COL/FXEN (21) Floating configures the device for full AN0 (4) AN1 (3) (48) FXSD+/CD+ (47) FXSD-/CD- bs Auto-Negotiation (49) FXRD-/AUIRD- NC NC THIN/REPEATER (63) This point should be tied directly to the TW_AVDD power pin NC 0.1uF 0.0033uF TW_AVDD NC NC 69.8K (60) TWREF 10K SPEED10 (5) GND NC (43) FXTD+/AUITD+ (44) FXTD-/AUITD- SERIAL10 (69) NC Active High Reset Input (500us min) O RESET (1) X1 (9) X2 (8) 4.87K (61) BGREF TWAGND (42) LED_COL/PHYAD0 (41) LED_TX/PHYAD1 (40) LED_RX/PHYAD2 (39) LED_LINK/PHYAD3 (38) LED_FDPOL/PHYAD4 VDD 10K 10K 10K 10K 10K 25MHz Xtal 50ppm NC (62) NC (59) NC (58) NC (56) NC (55) 33pF NC (2) 33pF GND 1K VCC 1K 1K GND 1K NC NC NC NC NC NC 1K This configuration results in a PHY address of 00001 GND GND Figure 22. Typical Implementation of 10/100 Mb/s Node Application 6.3 Power Plane Considerations vided herein represent a more simplified approach when compared to earlier recommendations. By reducing the The recommendations for power plane considerations pronumber of instances of plane partitioning within a given 38 www.national.com 6.0 DP83843 Application (Continued) system design, empirical data has shown a resultant improvement (reduction) in radiated emissions testing. Additionally, by eliminating power plane partitioning within the system VCC and system ground domains, specific impedance controlled signal routing can remain uninterrupted. By placing chassis ground on the top and bottom layers, additional EMI shielding is created around the 125Mb/s signal traces that must be routed between the magnetics and the RJ45-8 media connector. The example in Figure 24 assumes the use of Micro-Strip impedance control techniques for trace routing. Figure 24 illustrates a way of creating isolated power sources using beads on surface traces. No power or ground plane partitioning is implied or required. VCC FB TW_AGND(#64) SUB_GND1(#70) GND VCC 0.1UF te IO_VDD1(#6), IO_VDD2(#16), IO_VDD3(#26), IO_VDD5(#36) CD_VDD0(#72), CD_VDD1(#76), PCS_VDD(#10) CD_GND0(#71), CD_GND1(#75), PCS_VSS(#11) bs DP83843 GND O VCC GND ALL CAPS ARE 16V CERAMIC = FERRITE BEAD TDK # HF70ACB-321611T 26 AT 100MHZ AUIFX_VDD(#46) TR_AGND(#80) SUB_GND2(#77) TR_AVDD(#79) ATP_GND(#57) VCC 0.1UF GND GND VCC 0.001UF 0.1UF 10UF IO_VSS1(#7), IO_VSS2(#17), IO_VSS3(#27), IO_VSS4(#32), IO_VSS5(#37) AUIFX_GND(#45) FB ol e TW_AVDD(#68) CP_AGND(#51) 0.1UF 0.0033UF GND 0.1UF GND CP_AVDD(#52) FB FB 0.001UF CPTW_DVSS(#53) VCC VCC 0.0033UF CPTW_DVDD(#54) ALTHOUGH THE FB'S TO GND REDUCE NOISE ON THESE TWO CRITICAL PINS, THEY MAY INCREASE EMI EMISSIONS. THEREFORE, DEPENDING ON YOUR APPLICATION THEY MAY OR MAY NOT BE A BENEFIT. FB GND 0.1UF GND Figure 23. Power and Ground Filtering for the DP83843 39 www.national.com 6.0 DP83843 Application (Continued) Chassis Ground Layer 1 (top) Ground Plane: Chassis Signal Routing Magnetics DP83843 RJ45 Layer 2 te System Ground Signal Routing DP83843 Magnetics ol e Ground Plane: System Ground RJ45 System Ground Layer 3 bs VCC System VCC Signal Routing Planes: DP83843 Magnetics RJ45 O System VCC System VCC Chassis Ground Layer 4 (bottom) Ground Plane: Signal Routing DP83843 Magnetics RJ45 Chassis Figure 24. Typical plane layout recommendation for DP83843 40 www.national.com 6.0 DP83843 Application (Continued) For applications where high reliability is required, it is recommended that additional ESD protection diodes be added as shown below. There are numerous dual series connected diode pairs that are available specifically for ESD protection. The level of protection will vary dependent upon the diode ratings. The primary parameter that affects the level of ESD protection is peak forward surge current. Typical specifications for diodes intended for ESD protection range from 500mA (Motorola BAV99LT1 single pair diodes) In the case of an installed Ethernet system however, the to 12A (STM DA108S1 Quad pair array). network interface pins are still susceptible to external ESD Since performance is dependent upon components used, events. For example, a category 5 cable being dragged board impedance characteristics, and layout, the circuit across a carpet has the potential of developing a charge should be completely tested to ensure performance to the well above the typical 2kV ESD rating of a semiconductor required levels. device. 6.3.1 ESD Protection Typically, ESD precautions are predominantly in effect when handling the devices or board before being installed in a system. In those cases, strict handling procedures can be implemented during the manufacturing process to greatly reduce the occurrences of catastrophic ESD events. After the system is assembled, internal components are usually relatively immune from ESD events. DP83843 10/100 te Vcc RJ-45 Diodes placed on the device side of the isolation transformer TX ol e Pin 1 Pin 2 bs Vcc Pin 3 O RX Pin 6 Figure 25. Typical DP83843 Network Interface with additional ESD protection 41 www.national.com 7.0 User Information 7.1 Link LED While in Force 100Mb/s Good Link not complete the negotiation since it is not advertising 100Mb/s capability. In an application in which the user only desires 10Mb/s operation and is being sent 100Mb/s signals, then the correct operation is to never complete the negotiation. Type: Information Hardware Problem: 7.3 10Mb/s Repeater Mode The Good Link LED (LED_LINK pin 39) will not assert when the DP83843BVJE is programmed to force good link in 100Mb/s mode. However, as long as the DP83843BVJE is configured for forced 100BASE-X operation and good link is forced for 100M operation, it will still be able to transmit data even though the good link LED is not lit. Type: Urgent Hardware Problem: The DP83843BVJE is not designed to support the use of certain AUI attachments in repeater applications nor will it When the DP83843BVJE is configured for forced good link directly support 10Mb/s repeater applications while in in 100Mb/s mode, by setting bit 6 of the PCS register 10Mb/s serial or nibble mode. (address 16h), the LINK_LED pin will not assert unless an Description: internal state machine term, referred to as Cipher_In_Sync When implementing repeater applications which include a (aka CIS), is asserted. The assertion of CIS is based on Coaxial Transceiver Interface (CTI) connected to the the receive descrambler either being bypassed or becom- DP83843 AUI interface, CRS will be asserted due to transing synchronized with the receive scrambled data stream. mit data because the transmit data is looped back to the te Description: As long as the DP83843BVJE is configured for forced receive channel at the CTI transceiver. The assertion of 100BASE-X operation however, setting bit 6 of the PCS CRS during transmit will result in undue collisions at the repeater controller. register (address 16h) will allow for transmission of data. Additionally, because there is no way to guarantee phase In order to assert the Link LED while in Forced Good Link alignment of the 10MHz TX_CLK between multiple PHYTERs in a serial 10M repeater application (same is 100Mb/s mode, the user may select one of two options: true for 2.5MHz TX_CLK in 10Mb/s nibble mode), assum1: After setting bit 6 of the PCS register (address 16h), the ing each PHYTER is referenced to a single 25MHz X1 user may connect the DP83843BVJE to a known good far- clock signal, it is impossible to meet the input set and hold end link partner that is transmitting valid scrambled IDLEs. requirements across all ports during a transmit operation. This will assert the internal CIS term and, in turn, assert Solution: the Link LED. ol e Solution / Workaround: bs 2: After setting bit 6 of the PCS register (address 16h), the user may then assert bit 12 of the LBR register (address 17h) to bypass the scrambler/descrambler. This will assert the internal CIS term and, in turn, assert the Link LED. The user should then clear bit 12 of the LBR register (address 17h) to re-engage the scrambler/descrambler to allow for normal scrambled operation while in forced good link 100Mb/s mode. 7.2 False Link Indication When in Forced 10Mb/s Type: O Informational Hardware Problem: It is not recommended that the DP83843BVJE be used for AUI repeater applications where the transmit data is looped back to the receive channel at the transceiver. (i.e. CTI). Additionally, 10M serial and nibble repeater applications are not currently directly supported. 7.4 Resistor Value Modifications Type: Urgent Hardware Problem: To ensure optimal performance, the DP83843BVJE bandgap reference and receive equalization reference resistor values require updating. The DP83843BVJE will indicate valid link status when Description: forced to 10Mb/s (without Auto-Negotiation) while receiving The internal bandgap reference of the DP83843BVJE is 100BASE-TX scrambled Idles. slightly offset which results in an offset in various IEEE Description: conformance parameters such as VOD. The DP83843BVJE can incorrectly identify 100BASE-TX scrambled Idles being received as valid 10BASE-T energy and consequently indicate a valid link by the assertion of the Link LED as well as by setting the Link Status bit (bit 2) in the BMSR (reg 01h). The internal adaptive equalization reference bias is also slightly offset which can result in slightly reduced maximum cable length performance. Solution / Workaround: In order to set the proper internal bandgap reference, it is recommended that the value of the resistor connected to Do not force 10Mb/s operation. Instead, use Auto-Negotia- the BGREF pin (pin 61) be set to 4.87K (1/10th Watt tion to advertise 10BASE-T full and/or half duplex (as resistor with a 1% tolerance is recommended). This resisdesired) via the ANAR register (reg 04h) tor should be connected between the BGREF pin and By using Auto-Negotiation and only specifying 10BASE-T TW_AGND. (either half or full duplex), the DP83843BVJE will recognize In order to ensure maximum cable length performance for the scrambled idles as a valid 100Mb/s stream, but it will 100BASE-TX operation, it is recommended that a 70K Solution / Workaround: 42 www.national.com O bs ol e te resistor be placed between the TWREF pin (pin 60) and Description: TW_AGND. (1/10th Watt resistor with a 1% tolerance is The Next Page Toggle bit is used only in Next Page operarecommended) tions, and is used to distinguish one page from another. The AutoNegotiation specification indicates that the toggle 7.5 Magnetics bit should take on an initial value equal to that of bit 11 in Type: the ANAR, Reg 4h. Informational Hardware The DP83843BVJE incorrectly initializes this bit to 0, indeProblem: pendent of the setting of bit 11 in the ANAR. Note that this bit is a RESERVED bit in the 802.3 specification, and N/A defaults to 0 for all combinations of strap options. Description: If the user were to program both the Next Page bit, bit 15, The DP83843BVJE has been extensively tested with the and the RESERVED bit, bit 11, to a logic 1 to perform a following single package magnetics: next page type negotiation, and the partner node also supported next page operation, then the negotiation would not Valor PT4171 and ST6118 complete due to the initial wrong polarity of the toggle bit. Bel Fuse S558-5999-39 Solution / Workaround: Pulse H1086 Do not set RESERVED bit 11 (reg 04h) to a logic 1 if you Solution / Workaround: plan to perform next page operations. Please note that one of the most important parameters that is directly affected by the magnetics is 100BASE-TX Out- 7.7 Base Page to Next Page Initial FLP Burst put Transition Timing. Even with the Valor PT4171S mag- Spacing netics, it is possible, depending on the system design, Type: layout, and associated parasitics, the output transition Informational Hardware times may need to be further controlled. Problem: In order to help control the output transition time of the 100BASE-TX transmit signal, the user may wish to place a In performing Next Page Negotiation, the FLP burst spaccapacitive load across the TPTD+/- pins as close to these ing on the initial burst when changing from the Base Page pins as possible. However, because every system is differ- to the Next Page can be as long as 28ms. The 802.3u ent, it is suggested that the system designer experiment specification, Clause 28 sets a maximum of 22.3ms. Thus, with the capacitive value in order to obtain the desired there is a potential violation of 5.7ms. results. Description: Note that the board layout, the magnetics, and the output This anomaly is due to the handshake between the arbitrasignal of the DP83843BVJE each contribute to the final rise tion and transmit state machines within the device. All other and fall times as measured across the RJ45-8 transmit FLP burst to burst spacings, either base page or next page, pins. It should be noted that excessive capacitive loading will be in the range of 13ms to 15ms. across the TPTD+/- pins may result in improper transmit return loss performance at high frequencies (up to 80MHz). Note that the violating burst causes NO functional probFinally, when performing 100Mb/s transmit return loss lems for either base page or next page exchange. This is measurements, it is recommended that the DP83843BVJE due to the fact that the nlp_test_max_timer in the receive state machine has a minimum specification of 50ms, and be placed in True Quiet mode as described here: the nlp_test_min_timer has a minimum specification of In order to configure the PHYTER for "True Quiet" opera- 5ms. Thus, even if the transmitter waits 28ms vs. 22.3ms tion, the following software calls should occur via the serial between FLP bursts, the nlp_test_max_timer will not have MII management port following normal initialization of the come close to expiring. (50 + 5 - 28) = 27ms slack time. device: Solution. - Write 01h to register 1Fh (this enables the extended NOT APPLICABLE, Not a functional problem register set) - Write 02h to register 05h (this disables the NRZI 7.8 100Mb/s FLP Exchange Followed by Quiet encoder, required for True Quiet) Type: - write 00h to register 1Fh (this exits the extended register Informational Hardware set) Problem: - Set bit 9 of register 16h (this enables TX_QUIET which The scenario is when the DP83843BVJE and another stastops transmitting 100M IDLEs)) tion are BOTH using AutoNegotiation AND advertising 7.6 Next Page Toggle Bit Initialization 100mb full or half. If both units complete the FLP exchange properly, but the partner does NOT send any idles (a Type: FAULT condition), then the DP83843BVJE will get into a Urgent Software state in which it constantly sends 100mb idles and looks for 100mb idles from the partner. Problem: The DP83843BVJE's Next Page Toggle bit initializes to 0 independent of the value programmed in bit 11 of the Advertised Abilities Register (ANAR), Reg 4h 43 www.national.com Description: 7.10 BAD_SSD Event Lockup The symptoms of this problem include: Type: Register 1: Will show negotiation NOT complete (bit 5 = 0) Urgent Hardware Register 6: Will show a page received, then page receive Problem: will be cleared on read of this register (bit 1 = 1, then bit 1 = When the PHYTER receives a particular invalid data 0 if read twice) sequence, it can get stuck in the RX_DATA state with an Register 1a: Will have the data 00a3 invalid alignment. It will not recover until the link is broken or software intervenes. The required data sequence looks Solution / Workaround: like a bad_ssd event (I,J, followed by symbol with MSB=0), The workarounds include (these are mutually exclusive): followed eventually by a good IJK pattern before seeing 10 1. Provide a 100mb data stream to the DP83843BVJE (fix consecutive idle bits. The data pattern also has to show up on a specific alignment. the problem) Description: Root cause is that the transition from BAD_SSD state to the CARRIER_DET state, which can only occur if there is a single IDLE between packets, does not cause a re-loading of the data alignment. If the Bad SSD event which preceded this met certain conditions defined above, then the alignment logic is in an invalid state and the state machine will not be able to detect an end of frame condition. te 2. Force 10mb mode by writing 0000h (half10) or 0100 (full10) to Register 0. This is a logical progression since the 100mb side of the partner logic is down. 3. If you want to run AutoNegotiation again, with reduced capabilities or all capabilities: Turn off AutoNegotiation by writing a 0000h to Register 0. (Need to do this to clear the DP83843 from sending idles.) ol e Change the capabilities to the desired configuration by writing to Register 4 (0061 for full10/half10, or 0021 for half10 Solution: only, etc.) There is no workaround available. Since the data pattern Enable AutoNegotiation by writing a 1200 to Register 0. should never occur on a normally operating network, it has been decided that no corrective action is required for the (This restarts AutoNegotiation as well) current product. 7.9 Common Mode Capacitor for EMI improvement Type: Informational Hardware Problem: As with any high-speed design it is always practical to take precautions regarding the design and layout of a system to attempt to ensure acceptable EMI performance. bs Description: In an attempt to improve the EMI performance of a DP83843BVJE based PCI Node Card, a 10pF capacitor was installed from the center-tap of the primary winding of the transmit transformer to gnd. This common mode capacitive filtering improved (reduced) the EMI emissions by several dB at critical frequencies when tested in an FCC certified open field test site. O Solution / Workaround: It is recommended that the footprint for a typical ceramic chip cap be included on all new DP83843BVJE based designs to allow for the experimentation of EMI improvement. Again, a component footprint for the 10pF capacitor should be installed from the center-tap of the primary winding of the transmit transformer to system gnd. The inclusion of this capacitor should have no deleterious effect on the differential signalling of the transmitted signal. In fact, because of the unique current source transmitter of the DP83843BVJE, this center-tap cap has been shown to actually improve some of the signal characteristics such as rise/fall times and transmit return loss. When including this component in a given design, it is recommended that it be connected from the transmit transformer primary center-tap directly to ground with an absolute minimum of routing (preferably just an immediate via to the ground plane). 44 www.national.com 8.0 Register Block 8.1 Register Definitions Register maps and address definitions are given in the following tables: Table 5. Register Block - Phyter Register Map Offset Access Tag Description 00h RW BMCR Basic Mode Control Register 01h RO BMSR Basic Mode Status Register 02h RO PHYIDR1 PHY Identifier Register #1 03h RO PHYIDR2 PHY Identifier Register #2 04h RW ANAR Auto-Negotiation Advertisement Register 05h RW ANLPAR Auto-Negotiation Link Partner Ability Register 06h RW ANER Auto-Negotiation Expansion Register 07h RW ANNPTR Auto-Negotiation Next Page TX Reserved Reserved te 08h-0Fh RO PHYSTS PHY Status Register 11h RW MIPSCR MII Interrupt PHY Specific Control Register 12h RO MIPGSR MII Interrupt PHY Generic Status Register 13h RW DCR Disconnect Counter Register 14h RW FCSCR False Carrier Sense Counter Register 15h RW RECR Receive Error Counter Register 16h RW PCSR PCS Sub-Layer Configuration and Status Register 17h RW LBR Loopback and Bypass Register 18h RW 10BTSCR 10BASE-T Status & Control Register 19h RW PHYCTRL PHY Control Register Reserved Reserved 1Ah-1Fh ol e 10h bs In the register definitions under the `Default' heading, the following definitions hold true: O -- RW = Read/Write; Register bit is able to be read and written to by software -- RO = Read Only; Register bit is able to be read but not written to by software -- L(H) = Latch/Hold; Register bit is latched and held until read by software based upon the occurrence of the corresponding event -- SC = Self Clear; Register bit will clear itself after the event has occurred without software intervention -- P = Permanent; Register bit is permanently set to the default value and no action will cause the bit to change 45 www.national.com 8.0 Register Block (Continued) Table 6. Basic Mode Control Register (BMCR) Address 00h Bit 15 Bit Name Default Reset 0, RW/SC Description Reset: 1 = Initiate software Reset / Reset in Process 0 = Normal operation This bit sets the status and control registers of the PHY to their default states. This self-clearing bit returns a value of one until the reset process is complete (approximately 1.2 ms for reset duration). Reset is finished once the Auto-Negotiation process has begun or the device has entered its forced mode. 14 Loopback 0, RW Loopback: 1 = Loopback enabled 0 = Normal operation te The loopback function enables MII transmit data to be routed to the MII receive data path. Setting this bit may cause the descrambler to lose synchronization and produce a 500 s "dead time" before any valid data will appear at the MII receive outputs. 13 Speed Selection Strap, RW Speed Select: ol e 1 = 100 Mb/s 0 = 10 Mb/s Link speed is selected by this bit or by Auto-Negotiation if bit 12 of this register is set (in which case, the value of this bit is ignored) At reset, this bit is set according to the strap configuration of the AN0 and AN1 pins. After reset, this bit may be written to by software. Auto-Negotiation En- Strap, RW able Auto-Negotiation Enable: 1 = Auto-Negotiation Enabled - bits 8 and 13 of this register are ignored when this bit is set. bs 12 0 = Auto-Negotiation Disabled - bits 8 and 13 determine the link speed and mode. At reset, this bit is set according to the strap configuration of the AN0 and AN1 pins. After reset, this bit may be written to by software. Power Down O 11 0, RW Power Down: 1 = Power Down 0 = Normal Operation Setting this bit configures the PHYTER for minimum power requirements.While in Power Down mode, the PHYTER is not capable of transmitting or receiving data on an active network. Additionally, the PHYTER is not capable of "Wake-on-LAN" and will not react to receive data while in Power Down mode. Power Down mode is useful for scenarios where minimum system power is desired (ie. Green PCs) but can only be used in systems that have control over the PHYTER via Serial MII management. 46 www.national.com 8.0 Register Block (Continued) Table 6. Basic Mode Control Register (BMCR) Address 00h (Continued) Bit 10 Bit Name Default Isolate Strap, RW Description Isolate: 1 = Isolates the DP83843 from the MII with the exception of the serial management. When this bit is asserted, the DP83843 does not respond to TXD[3:0], TX_EN, and TX_ER inputs, and it presents a high impedance on its TX_CLK, RX_CLK, RX_DV, RX_ER, RXD[3:0], COL and CRS outputs. 0 = Normal operation If the PHY address is set to "00000" at power-up/reset the isolate bit will be set to one, otherwise it defaults to 0. After reset this bit may be written to by software. Restart Auto-Negoti- 0, RW/SC ation Restart Auto-Negotiation: 1 = Restart Auto-Negotiation. Re-initiates the Auto-Negotiation process. If Auto-Negotiation is disabled (bit 12 of this register cleared), this bit has no function and should be cleared. This bit is self-clearing and will return a value of 1 until Auto-Negotiation is initiated by the Device, whereupon it will self-clear. Operation of the Auto-Negotiation process is not affected by the management entity clearing this bit. te 9 0 = Normal operation Duplex Mode Strap, RW Duplex Mode: ol e 8 1 = Full Duplex operation. Duplex selection is allowed when AutoNegotiation is disabled (bit 12 of this register is cleared). 0 = Half Duplex operation At reset this bit is set by either AN0 or AN1. After reset this bit may be written to by software. 7 Collision Test 0, RW Collision Test: 1 = Collision test enabled 0 = Normal operation bs When set, this bit will cause the COL signal to be asserted in response to the assertion of TX_EN within 512BT. The COL signal will be de-asserted within 4BT in response to the de-assertion of TX_EN. 6:0 Reserved 0, RO Reserved: Write ignored, read as zero O Table 7. Basic Mode Status Register (BMSR) Address 01h Bit 15 14 Bit Name 100BASE-T4 Default 0, RO/P Description 100BASE-T4 Capable: 1 = Device able to perform in 100BASE-T4 mode 0 = Device not able to perform in 100BASE-T4 mode The PHYTER is NOT capable of supporting 100BASE-T4 and this bit is permanently set to 0. 100BASE-TX Full Duplex 1, RO/P 100BASE-TX Half Duplex 1, RO/P 100BASE-TX Full Duplex Capable: 1 = Device able to perform 100BASE-TX in full duplex mode 0 = Device not able to perform 100BASE-TX in full duplex mode 13 100BASE-TX Half Duplex Capable: 1 = Device able to perform 100BASE-TX in half duplex mode 0 = Device not able to perform 100BASE-TX in half duplex mode 47 www.national.com 8.0 Register Block (Continued) Table 7. Basic Mode Status Register (BMSR) Address 01h (Continued) Bit 12 Bit Name Default 10BASE-T Full Duplex 1, RO/P 10BASE-T Half Duplex 1, RO/P Description 10BASE-T Full Duplex Capable: 1 = Device able to perform 10BASE-T in full duplex mode 0 = Device not able to perform 10BASE-T in full duplex mode 11 10BASE-T Half Duplex Capable: 1 = Device able to perform 10BASE-T in half duplex mode 0 = Device not able to perform 10BASE-T in half duplex mode 10:7 Reserved 0, RO Reserved: Write as 0, read as 0 6 Preamble 1, RO/P Preamble suppression Capable: Suppression 1 = Device able to perform management transaction with preamble suppressed* te 0 = Device not able to perform management transaction with preamble suppressed * Need minimum of 32 bits of preamble after reset. 5 Auto-Negotiation Complete 0, RO Auto-Negotiation Complete: 1 = Auto-Negotiation process complete 0 = Auto-Negotiation process not complete Remote Fault 0, RO/LH Remote Fault: ol e 4 1 = Remote Fault condition detected (cleared on read or by a chip reset). Fault criteria is Far End Fault Isolation or notification from Link Partner of Remote Fault. 0 = No remote fault condition detected 3 Auto-Negotiation Ability 1, RO/P Link Status 0, RO/L Auto Configuration Ability: 1 = Device is able to perform Auto-Negotiation 0 = Device is not able to perform Auto-Negotiation 2 Link Status: bs 1 = Valid link established (for either 10 or 100 Mb/s operation) 0 = Link not established The criteria for link validity is implementation specific. The link status bit is implemented with a latching function, so that the occurrence of a link failure condition causes the Link Status bit to become cleared and remain cleared until it is read via the management interface. Jabber Detect O 1 0 Extended Capability 0, RO/L Jabber Detect: 1 = Jabber condition detected 0 = No Jabber This bit is implemented with a latching function so that the occurrence of a jabber condition causes it to become set until it is cleared by a read to this register by the management interface or by a Device Reset. This bit only has meaning in 10 Mb/s mode. 1, RO/P Extended Capability: 1 = Extended register capable 0 = Basic register capable only 48 www.national.com 8.0 Register Block (Continued) The PHY Identifier Registers #1 and #2 together form a unique identifier for the DP83843. The Identifier consists of a concatenation of the Organizationally Unique Identifier (OUI), the vendor's model number and the model revision number. A PHY may return a value of zero in each of the 32 bits of the PHY Identifier if desired. The PHY Identifier is intended to support network management. National's IEEE assigned OUI is 080017h. Table 8. PHY Identifier Register #1 (PHYIDR1) Address 02h Bit 15:0 Bit Name Default OUI_MSB Description <00 1000 0000 OUI Most Significant Bits: This register stores bits 3 to 18 of the 0000 00>, RO/P OUI (080017h) to bits 15 to 0 of this register respectively. The most significant two bits of the OUI are ignored (the IEEE standard refers to these as bits 1 and 2). Table 9. PHY Identifier Register #2 (PHYIDR2) Address 03h 15:10 9:4 Bit Name Default OUI_LSB VNDR_MDL 3:0 MDL_REV Description <01 0111>, RO/P OUI Least Significant Bits: <00 0001>, RO/P Vendor Model Number: <0000>, RO/P Model Revision Number: Bits 19 to 24 of the OUI (080017h) are mapped to bits 15 to 10 of this register respectively. te Bit Six bits of vendor model number mapped to bits 9 to 4 (most significant bit to bit 9). ol e Four bits of vendor model revision number mapped to bits 3 to 0 (most significant bit to bit 3). This field will be incremented for all major device changes. This register contains the advertised abilities of this device as they will be transmitted to its Link Partner during AutoNegotiation. Table 10. Auto-Negotiation Advertisement Register (ANAR) Address 04h Bit 15 Bit Name NP Default 0, RW Description Next Page Indication: bs 0 = Next Page Transfer not desired 1 = Next Page Transfer desired 14 13 Reserved 0, RO/P Reserved by IEEE: Writes ignored, Read as 0 RF 0, RW Remote Fault: 1 = Advertises that this device has detected a Remote Fault 0 = No Remote Fault detected Reserved 0, RW Reserved for Future IEEE use: Write as 0, Read as 0 FDFC 0, RW Full Duplex Flow Control: O 12:11 10 9 T4 1 = Advertise that the DTE(MAC) has implemented both the optional MAC control sublayer and the pause function as specified in clause 31 and annex 31B of 802.3u 0= No MAC based full duplex flow control 0, RO/P 100BASE-T4 Support: 1= 100BASE-T4 is supported by the local device 0 = 100BASE-T4 not supported 8 TX_FD Strap, RW 100BASE-TX Full Duplex Support: 1 = 100BASE-TX Full Duplex is supported by the local device 0 = 100BASE-TX Full Duplex not supported At reset, this bit is set by AN0/AN1. After reset, this bit may be written to by software. 49 www.national.com 8.0 Register Block (Continued) Table 10. Auto-Negotiation Advertisement Register (ANAR) Address 04h (Continued) Bit 7 Bit Name Default TX Strap, RW Description 100BASE-TX Support: 1 = 100BASE-TX is supported by the local device 0 = 100BASE-TX not supported At reset, this bit is set by AN0/AN1. After reset, this bit may be written to by software. 6 10_FD Strap, RW 10BASE-T Full Duplex Support: 1 = 10BASE-T Full Duplex is supported by the local device 0 = 10BASE-T Full Duplex not supported At reset, this bit is set by AN0/AN1. After reset, this bit may be written to by software. 5 10 Strap, RW 10BASE-T Support: te 1 = 10BASE-T is supported by the local device 0 = 10BASE-T not supported At reset, this bit is set by AN0/AN1. After reset, this bit may be written to by software. 4:0 Selector <00001>, RW Protocol Selection Bits: ol e These bits contain the binary encoded protocol selector supported by this node. <00001> indicates that this device supports IEEE 802.3 CSMA/CD. Advertised abilities of the Link Partner as received during Auto-Negotiation. Table 11. Auto-Negotiation Link Partner Ability Register (ANLPAR) Address 05h Bit 15 Bit Name NP Default 0, RO Description Next Page Indication: bs 0 = Link Partner does not desire Next Page Transfer 1 = Link Partner desires Next Page Transfer 14 ACK 0, RO Acknowledge: 1 = Link Partner acknowledges reception of the ability data word 0 = Not acknowledged O The Device's Auto-Negotiation state machine will automatically control the use of this bit from the incoming FLP bursts. Software should not attempt to write to this bit. 13 RF 0, RO Remote Fault: 1 = Remote Fault indicated by Link Partner 0 = No Remote Fault indicated by Link Partner 12:10 Reserved 0, RO Reserved for Future IEEE use: Write as 0, read as 0 9 T4 0, RO 100BASE-T4 Support: 1 = 100BASE-T4 is supported by the Link Partner 0 = 100BASE-T4 not supported by the Link Partner 8 TX_FD 0, RO 100BASE-TX Full Duplex Support: 1 = 100BASE-TX Full Duplex is supported by the Link Partner 0 = 100BASE-TX Full Duplex not supported by the Link Partner 7 TX 0, RO 100BASE-TX Support: 1 = 100BASE-TX is supported by the Link Partner 0 = 100BASE-TX not supported by the Link Partner 50 www.national.com 8.0 Register Block (Continued) Table 11. Auto-Negotiation Link Partner Ability Register (ANLPAR) Address 05h Bit 6 Bit Name Default 10_FD 0, RO Description 10BASE-T Full Duplex Support: 1 = 10BASE-T Full Duplex is supported by the Link Partner 0 = 10BASE-T Full Duplex not supported by the Link Partner 5 10 0, RO 10BASE-T Support: 1 = 10BASE-T is supported by the Link Partner 0 = 10BASE-T not supported by the Link Partner 4:0 Selector <00000>, RO Protocol Selection Bits: O bs ol e te Link Partners's binary encoded protocol selector. 51 www.national.com 8.0 Register Block (Continued) Table 11. Auto-Negotiation Link Partner Ability Register (ANLPAR) Address 05h Bit Bit Name Default Description This register also contains the Link Partner Next Page contents. 15 NP X RO Next Page Indication: 0 = Link Partner does not desire another Next Page Transfer 1 = Link Partner desires another Next Page Transfer 14 ACK X, RO Acknowledge: 1 = Link Partner acknowledges reception of the ability data word 0 = Not acknowledged The Device's Auto-Negotiation state machine will automatically control the use of this bit from the incoming FLP bursts. Software should not attempt to write to this bit. 13 MP X, RO Message Page: te 1 = Message Page 0 = Unformatted Page 12 ACK2 X, RO Acknowledge 2: 0 = Link Partner does not have the ability to comply to next page message TOGGLE ol e 1 = Link Partner has the ability to comply to next page message 11 X, RO Toggle: 0 = Previous value of the transmitted Link Code word equalled logic one 1 = Previous value of the transmitted Link Code word equalled logic zero CODE XXX, RW This field represents the code field of the next page transmission. If the MP bit is set (bit 13 of this register), then the code shall be interpreted as a "Message Page," as defined in annex 28C of Clause 28. Otherwise, the code shall be interpreted as an "Unformatted Page," and the interpretation is application specific. bs 10:0 Table 12. Auto-Negotiation Expansion Register (ANER) Address 06h Bit 15:5 3 2 Default Description 0, RO Reserved: Writes ignored, Read as 0. PDF 0, RO Parallel Detection Fault: O 4 Bit Name Reserved LP_NP_ABLE NP_ABLE 1 = A fault has been detected via the Parallel Detection function 0 = A fault has not been detected via the Parallel Detection function 0, RO Link Partner Next Page Able: Status indicating if the Link Partner supports Next Page negotiation. A one indicates that the Link Partner does support Next Page. 1, RO/P Next Page Able: Indicates if this node is able to send additional "Next Pages." 1 PAGE_RX 0, RO/L Link Code Word Page Received: This bit is set when a new Link Code Word Page has been received. Cleared on read of this register. 0 LP_AN_ABLE 0, RO Link Partner Auto-Negotiation Able: A one in this bit indicates that the Link Partner supports Auto-Negotiation. 52 www.national.com 8.0 Register Block (Continued) This register contains the next page information sent by this device to its Link Partner during Auto-Negotiation. Table 13. Auto-Negotiation Next Page Transmit Register (ANNPTR) Address 07h Bit 15 Bit Name Default NP 0, RW Description Next Page Indication: 0 = No other Next Page Transfer desired 1 = Another Next Page desired 14 Reserved 0, RO Reserved: Writes ignored, read as 0 13 MP 1, RW Message Page: 1 = Message Page 0 = Unformatted Page 12 ACK2 0, RW Acknowledge2: 1 = Will comply with message 0 = Cannot comply with message 11 TOG_TX 1, RO te Acknowledge2 is used by the next page function to indicate that a device has the ability to comply with the message received. Toggle: 1 = Previous value of transmitted Link Code Word equalled logic 0 ol e 0 = Previous value of transmitted Link Code Word equalled logic 1 Toggle is used by the Arbitration function within Auto-Negotiation to ensure synchronization with the Link Partner during Next Page exchange. This bit shall always take the opposite value of the Toggle bit in the previously exchanged Link Code Word. The initial value is the inverse of bit 11 in the base Link Code Word (ANAR), which makes the default value of TOG_TX = 1. CODE 001, RW This field represents the code field of the next page transmission. If the MP bit is set (bit 13 of this register), then the code shall be interpreted as a "Message Page," as defined in annex 28C of Clause 28. Otherwise, the code shall be interpreted as an "Unformatted Page," and the interpretation is application specific. bs 10:0 O The default value of the CODE represents a Null Page as defined in annex 28C of Clause 28. 53 www.national.com 8.0 Register Block (Continued) This register provides a single location within the register set for quick access to commonly accessed information. Table 14. PHY Status Register (PHYSTS) Address 10h Bit 15 Bit Name Default Receive Error Latch 0, RO/L Description Receive Error Latch: 1 = Receive error event has occurred since last read of RXERCNT 0 = No receive error event has occurred 14 CIM Latch 0, RO/L Carrier Integrity Monitor Latch: 1 = Carrier Integrity Monitor has found an isolate event since last read of DCR 0 = No Carrier Integrity Monitor isolate event has occurred 13 False Carrier Sense Latch 0, RO/L False Carrier Sense Latch: 1 = False Carrier event has occurred since last read of FCSCR te 0 = No False Carrier event has occurred 12 Reserved 0, RO Reserved: Write ignored, read as 0. 11 Device Ready 0, RO Device Ready: This bit signifies that the device is now ready to transmit data. 1 = Device Ready 10 Page Received ol e 0 = Device not Ready 0, RO/L Link Code Word Page Received: This bit is set when a new Link Code Word Page has been received. Cleared on read of the ANER register. 9 Auto-Negotiation En- Strap, RO abled Auto-Negotiation Enabled: 1 = Auto-Negotiation Enabled. 0 = Auto-Negotiation Disabled. 8 MII Interrupt 0, RO/L MII Interrupt Pending: 7 bs Indicates that an internal interrupt is pending and is cleared by the current read. A read of this bit will clear the bit in the MIPGSR (12h) also. Remote Fault 0, RO/L Remote Fault: 1 = Remote Fault condition detected (cleared on read of BMSR register or by a chip reset). Fault criteria is Far end Fault Isolation or notification from Link Partner of Remote Fault. 0 = No remote fault condition detected Jabber Detect O 6 5 NWAY Complete 0, RO/L Jabber Detect: 1 = Jabber condition detected 0 = No Jabber This bit is implemented with a latching function so that the occurrence of a jabber condition causes it to become set until it is cleared by a read to the BMSR register by the management interface or by a Device reset. This bit only has meaning in 10 Mb/s mode. 0, RO Auto-Negotiation Complete: 1 = Auto-Negotiation complete 0 = Auto-Negotiation not complete 4 Reset Status 0, RO Reset Status: 0 = Normal operation 1 = Reset in progress 54 www.national.com 8.0 Register Block (Continued) Table 14. PHY Status Register (PHYSTS) Address 10h (Continued) Bit 3 Bit Name Default Loopback Status 0, RO Description Loopback: 1 = Loopback enabled 0 = Normal operation 2 Duplex Status RO Duplex: This bit indicates duplex status and is determined from Auto-Negotiation or Forced Modes. 1 = Running in Full duplex mode 0 = Running in Half duplex mode Note: This bit is only valid if Auto-Negotiation is enabled and complete and there is a valid link or if Auto-Negotiation is disabled and there is a valid link. Speed Status RO Speed10: te 1 This bit indicates the status of the speed and is determined from Auto-Negotiation or Forced Modes. 1 = Running in 10Mb/s mode 0 = Running in 100 Mb/s mode 0 Link Status ol e Note: This bit is only valid if Auto-Negotiation is enabled and complete and there is a valid link or if Auto-Negotiation is disabled and there is a valid link. 0, RO Link Status: 1 = Valid link established (for either 10 or 100 Mb/s operation) 0 = Link not established The criteria for link validity is implementation specific. Bit 15:2 1 bs This register implements the MII Interrupt PHY Specific Control register. Sources for interrupt generation include: Link State Change, Jabber Event, Remote Fault, Auto-Negotiation Complete or any of the counters becoming half-full. Note that the TINT bit operates independently of the INTEN bit. In other words, INTEN does not need to be active to generate the test interrupt. Table 15. MII Interrupt PHY Specific Control Register (MIPSCR) Address 11h Bit Name Default Description Reserved 0, RO Reserved: Writes ignored, Read as 0 INTEN 0, RW Interrupt Enable: O 1 = Enable event based interrupts 0 TINT 0 = Disable event based interrupts 0, RW Test Interrupt: Forces the PHY to always generate an interrupt to allow testing of the interrupt. 1 = Generate an interrupt at the end of each access 0 = Do not generate interrupt This register implements the MII Interrupt PHY Generic Status Register. Table 16. MII Interrupt PHY Generic Status Register (MIPGSR) Address 12h Bit 15 Bit Name MINT Default 0, RO/COR Description MII Interrupt Pending: Indicates that an interrupt is pending and is cleared by the current read. A read of this will also clear the MII Interrupt bit (8) of the PHYSTS (10h) register. 14:0 Reserved 0, RO Reserved: Writes ignored, Read as 0 55 www.national.com 8.0 Register Block (Continued) This counter provides information required to implement the isolates attribute within the Repeater Port managed object class of Clause 30 of the IEEE 802.3 specification. Table 17. Disconnect Counter Register (DCR) Address 13h Bit 15:0 Bit Name Default DCNT[15:0] <0000h>, RW / COR Description Disconnect Counter: This 16 bit counter increments for each isolate event. Each time the CIM detects a transition from the False Carrier state to the Link Unstable state of the Carrier Integrity State Machine, the counter increments. This counter rolls over when it reaches its max count (FFFFh). This counter provides information required to implement the FalseCarriers attribute within the MAU managed object class of Clause 30 of the IEEE 802.3 specification. Table 18. False Carrier Sense Counter Register (FCSCR) Address 14h 15:0 Bit Name Default FCSCNT[15:0] <0000h>, RW / COR Description False Carrier Event Counter: te Bit This 16 bit counter increments for each false carrier event. A false carrier event occurs when carrier sense is asserted without J/K symbol detection. This counter rolls over when it reaches its max count (FFFFh). Bit RXERCNT[15:0] Default <0000h>, RW / COR Description RX_ER Counter: This 16 bit counter is incremented for each receive error detected. The counter is incremented when valid carrier is present and there is at least one occurrence of an invalid data symbol. This event can increment only once per valid carrier event. If a collision is present, this attribute will not increment. This counter rolls over when it reaches its max count (FFFFh). bs 15:0 Bit Name ol e This counter provides information required to implement the aSymbolErrorDuringCarrier attribute within the PHY managed object class of Clause 30 of the IEEE 802.3 specification. Table 19. Receive Error Counter Register (RECR) Address 15h Table 20. 100 Mb/s PCS Configuration and Status Register (PCSR) Address 16h Bit 15 Bit Name Single_SD Default 0, RW Description SIngle Ended Signal Detect Enable: 1=Single Ended SD mode enabled O 0=Single Ended SD mode disabled 14 13 FEFI_EN DESCR_TO_RST Strap, RW Far End Fault Indication Mode: 1 = FEFI mode enabled 0 = FEFI mode disabled Note: If Auto-Negotiation is enabled, bit 12 of BMCR, this bit is RO and forced to zero. Additionally, if FX_EN is set to a one then this bit is RO and forced to a one. 0, RW Reset Descrambler Time-Out Counter: 1 = Reset Time-Out Counter 0 = Normal operation 56 www.national.com 8.0 Register Block (Continued) Table 20. 100 Mb/s PCS Configuration and Status Register (PCSR) Address 16h (Continued) Bit 12 Bit Name Default DESCR_TO_SEL 0, RW Description Descrambler Time-out Select: 1 = Descrambler Timer set to 2 ms 0 = Descrambler Timer set to 722 s The Descrambler Timer selects the interval over which a minimum number of IDLES are required to be received to maintain descrambler synchronization. The default time of 722 s supports 100BASE-X compliant applications. A timer time-out indicates a loss of descrambler synchronization which cause the descrambler to restart its operation by immediately looking for IDLES. 11 DESCR_TO_DIS 0, RW te The 2 ms option allows applications with Maximum Transmission Units (packet sizes) larger than IEEE 802.3 to maintain descrambler synchronization (i.e., Token Ring/Fast-Ethernet switch/router applications). Descrambler Time-out Disable: 1 = Time-out Counter in the descrambler section of the receiver disabled 0 = Time-out Counter enabled LD_SCR_SD 0, RW Load Scrambler Seed: ol e 10 1 = Load Scrambler Seed continuously 0 = Normal operation 9 TX_QUIET 0, RW 100 Mps Transmit True Quiet Mode: 1 = Transmit True Quiet mode 0 = Normal mode 8:7 TX_PATTERN[1:0] <00>, RW 100 Mps Transmit Test Pattern: <00> = Normal operation bs <01> = Send FEFI pattern <10> = Send 1.28 speriod pattern (640 ns high/low time) <11> = Send 160 ns period pattern (80 ns high/low time) 6 F_LINK_100 0, RW Force Good Link in 100 Mb/s: 1 = Force 100 Mb/s Good Link status 0 = Normal 100 Mb/s operation O This bit is useful for diagnostic purposes. 5 CIM_DIS Strap, RW Carrier Integrity Monitor Disable: 1 = Carrier Integrity Monitor function disabled (Node/Switch operation) 0 = Carrier Integrity Monitor function enabled (Repeater operation) The THIN/REPEATER determines the default state of this bit to automatically enable or disable the CIM function as required for IEEE 802.3 compliant applications. The value latched into this bit at power-on/reset is the compliment of the value forced on the THIN/REPEATER input. After power-on/reset, software may enable or disable this function independent of repeater or node/switch mode. 57 www.national.com 8.0 Register Block (Continued) Table 20. 100 Mb/s PCS Configuration and Status Register (PCSR) Address 16h (Continued) Bit 4 Bit Name Default CIM_STATUS 0, RO Description Carrier Integrity Monitor Status: This bit indicates the status of the Carrier Integrity Monitor function. This status is optionally muxed out through the TX_LED pin when the LED_TXRX_MODE bits (8:7) of the PHYCTRL register (address 19h) are set to either <10> or <01>. 1 = Unstable link condition detected 0 = Unstable link condition not detected 3 CODE_ERR 0, RW Code Errors: 1 = Forces code errors to be reported with the value 5h on RXD[3:0] and with RX_ER set to 1. 0 = Forces code errors to be reported with the value of 6h on RXD[3:0] and with RX_ER set to 1. PME_ERR 0, RW Premature End Errors: te 2 1 = Forces premature end errors to be reported with the value 4h on RXD[3:0] and with RX_ER set to 1. 1 ol e 0 = Forces premature end errors to be reported with the value 6h on RXD[3:0] and with RX_ER set to 1. Premature end errors are caused by the detection of two IDLE symbols in the receive data stream prior to the T/R symbol pair denoting end of stream delimiter. LINK_ERR 0, RW Link Errors: 1 = Forces link errors to be reported with the value 3h on RXD[3:0] and with RX_ER set to 1. 0 = Data is passed to RXD[3:0] unchanged and with RX_ER set to 0. 0 PKT_ERR 0, RW Packet Errors: bs 1 = Forces packet errors (722 s time-out) to be reported with the value 2h on RXD[3:0] and with RX_ER set to 1. 0 = Data is passed to RXD[3:0] unchanged and with RX_ER set to 0. Table 21. Loopback & Bypass Register (LBR) Address 17h Bit Bit Name Reserved O 15 14 13 BP_STRETCH BP_4B5B Default Description 0, RO Reserved: Writes ignored, read as 0. 0, RW Bypass LED Stretching: This will bypass the LED stretching and the LEDs will reflect the internal value. 1 = Bypass LED stretching 0 = Normal operation Strap, RW Bypass 4B5B Encoding and 5B4B Decoding: This bit is set according to the strap configuration of the SYMBOL pin at power-up/reset. After reset this bit may be written to by software. 1 = 4B5B encoder and 5B4B decoder functions bypassed 0 = Normal 4B5B and 5B4B operation 58 www.national.com 8.0 Register Block (Continued) Table 21. Loopback & Bypass Register (LBR) Address 17h (Continued) Bit 12 Bit Name Default BP_SCR Strap, RW Description Bypass Scrambler/Descrambler Function: This bit is set according to the strap configuration of the SYMBOL pin or the FXEN pin at power-up/reset. After reset this bit may be written to by software. 1 = Scrambler and descrambler functions bypassed 0 = Normal scrambler and descrambler operation 11 BP_RX Strap, RW Bypass Receive Function: This bit is set according to the strap configuration of the SYMBOL pin at power-up/reset. After reset this bit may be written to by software. 1 = Receive functions (descrambler and symbol decoding functions) bypassed. 10 BP_TX Strap, RW te 0 = Normal operation. Bypass Transmit Function: This bit is set according to the strap configuration of the SYMBOL pin at power-up/reset. After reset this bit may be written by software. ol e 1 = Transmit functions (symbol encoder and scrambler) bypassed 0 = Normal operation 9:7 100_DP_CTL Strap, RW 100Mps Data Path Control Bits: At reset, if FXEN is true then this will default to <011>, else it will default to <000>. These bits control the 100Mps loopback function in CorePhy as follows: <000> Normal Mode <001> CorePhy Loopback <010> Reserved bs <011> Normal Fiber <100> Reserved <101> Reserved <110> Reserved <111> Reserved O Note: A write to the Loopback bit (14) of the BMCR (00h) will override the value set in this register. 6 RESERVED 0, RO Reserved: Writes as 0, read as 0 5 TW_LBEN 0, RW TWISTER Loopback Enable: 4 10Mb_ENDEC_LB 1 = TWISTER loopback 0 = Normal mode Note: A write to the Loopback bit (14) of the BMCR (00h) will override the value set in this register. 0, RW 10 Mb/s ENDEC Loopback: 1 = 10Mb/s ENDEC loopback 0 = Normal TREX operation Note: A write to the Loopback bit (14) of the BMCR (00h) will override the value set in this register. 3 RESERVED 0, RO Reserved: Writes as 0, read as 0 2 RESERVED 0, RO Reserved: Writes as 0, read as 0 59 www.national.com 8.0 Register Block (Continued) Table 21. Loopback & Bypass Register (LBR) Address 17h (Continued) Bit Bit Name Default Description 1 RESERVED 0, RO Reserved: Writes as 0, read as 0 0 RESERVED 0, RO Reserved: Writes as 0, read as 0 Table 22. 10BASE-T Control & Status Register (10BTSCR) Address 18h Bit Bit Name Default Description 15:14 RESERVED 0, RO Reserved: Writes ignored, read as 0 13 AUI_TPI 0, RO TREX Operating Mode: This bit shows the current operating mode of TREX as chosen by the Auto-Switch function. 1 = AUI mode 12 RX_SERIAL Strap, RW te 0 = TPI mode 10BASE-T RX Serial Mode: This bit is set according to the strap configuration of the SERIAL10 pin at power-up/reset. After reset this bit may be written to by software. 1 = 10BASE-T rx Serial mode selected ol e 0 = 10BASE-T rx Nibble mode selected Serial mode is not supported for 100 Mb/s operation. 11 TX_SERIAL Strap, RW 10BASE-T TX Serial Mode: This bit is set according to the strap configuration of the SERIAL_10 pin at power-up/reset. After reset this bit may be written to by software. 1 = 10BASE-T tx Serial mode selected 0 = 10BASE-T tx Nibble mode selected 10 bs Serial mode is not supported for 100 Mb/s operation. POL_DS 0, RW Polarity Detection & Correction Disable: 1 = Polarity Sense & Correction disabled 0 = Polarity Sense & Correction enabled 9 AUTOSW_EN 0, RW AUI/TPI Autoswitch: 1 = Enable autoswitch O 0 = Disable autoswitch function 8 LP_DS The use of autoswitch should be strictly limited to applications that do not support Auto-Negotiation. Do not enable Auto-Negotiation when enabling autoswitch as this may result in improper operation. 0, RW Link Pulse Disable: 1 = Reception of link pulses ignored, good link condition forced 0 = Good link not forced, link pulses observed for good link 7 HB_DS 0, RW Heartbeat Disable: 1 = Heartbeat function disabled 0 = Heartbeat function enabled When the device is configured for full duplex operation, this bit will be ignored (the collision/heartbeat function has no meaning in Full Duplex mode). HB_DS will read back as 1 if in Full Duplex mode or Repeater mode. 60 www.national.com 8.0 Register Block (Continued) Table 22. 10BASE-T Control & Status Register (10BTSCR) Address 18h (Continued) Bit 6 Bit Name Default LS_SEL 0, RW Description Low Squelch Select: Selects between standard 10BASE-T receiver squelch threshold and a reduced squelch threshold that is useful for longer cable applications. 1 = Low Squelch Threshold selected 0 = Normal 10BASE-T Squelch Threshold selected 5 AUI_SEL 0, RW AUI Select: 1 = Select AUI interface 0 = Select TPI interface 4 JAB_DS 0, RW Jabber Disable: te Enables or disables the Jabber function when the device is in 10BASE-T Full Duplex or 10BASE-T TREX Loopback mode (TREX_LBEN bit 4 in the LBR, address 17h). 1 = Jabber function disabled 0 = Jabber function enabled 3 THIN_SEL 0, RW Thin Ethernet Select: 1 = Asserts THIN pin (pin 63) ol e 0 = Deasserts THIN pin (pin 63) This pin may be used as a general purpose select pin. 2 RX_FILT_DS 0, RW TPI Receive Filter Disable: 1 = Disable TPI receive filter 0 = Enable TPI receive filter RESERVED 0 RESERVED 0, RO Reserved: Writes ignored, read as 0 0, RO Reserved: Writes as 0, read as 0 bs 1 Table 23. PHY Control Register (PHYCTRL) Address 19h Bit 15 14 Default Description RESERVED 0, RO Reserved: Writes ignored, read as 0 RESERVED 0, RO Reserved: Writes ignored, read as 0 TW_EQSEL[1:0] <00>, RW TWISTER Equalization Select: Used in combination to select the 4 equalization modes. Modes 3, 2, 1 should be accessible to external device pin for debug purposes. O 13:12 Bit Name <11> = Equalization off <10> = Equalization on <01> = Adaptive Equalization <00> = Full Adaptive Equalization 11 TW_BLW_DS 0, RW TWISTER Base Line Wander Disable: 1 = BLW Feedback loop disabled 0 = BLW Feedback loop enabled 10 RESERVED 0, RO Reserved: Writes ignored, read as 0 61 www.national.com 8.0 Register Block (Continued) Table 23. PHY Control Register (PHYCTRL) Address 19h (Continued) Bit 9 Bit Name Default REPEATER Strap, RW Description Repeater/Node Mode: 1 = Repeater mode 0 = Node mode In repeater mode the Carrier Sense (CRS) output from the device is asserted due to receive activity only. In Node mode, and not configured for full duplex operation, CRS is asserted due to either receive or transmit activity. In 100 Mb/s operation the CIM monitor is disabled. In Repeater mode HB_DS is enabled (bit 7 register 10BTSCR(18h)) This bit is set according to the strap configuration of the REPEATER pin at power-up/reset. 8:7 LED_TXRX_MODE <00>, RW LED_TX/RX Mode Select: te <11> = LED_RX indicates both RX and TX activity and LED_TX indicates interrupt. Interrupt signal is active high. <10> = LED_RX indicates both RX and TX activity and LED_TX indicates Carrier Integrity Monitor status.Interrupt signal is active high. <01> = LED_RX indicates RX activity only and LED_TX indicates Carrier Integrity Monitor status. ol e <00> = Normal LED_TX and LED_RX operation. Note: Using LED_TX to indicate Carrier Integrity Monitor status is useful for network management purposes in 100BASE-TX mode. This mode only works if the PHY_Address_2 is strapped low because the PHYTER does not properly implement the Activity LED function if LED_RX/PHYAD[2] is strapped high. 6 LED_DUP_MODE 0, RW LED_DUP Mode Select: 1 = LED_FDPOL configured to indicate polarity reversal in 10BASE-T mode, and full duplex in 100BASE-TX mode 5 bs 0 = LED_FDPOL configured to indicate full duplex in all operating modes. FX_EN Strap, RW Fiber Mode Enable: This bit is set by the FX_EN at power-on/reset or by software after reset. If this bit is set then the signals FEFI_EN and BP_SCR are driven internally. When this bit is set, fiber mode enabled, AutoNegotiation must be disabled. O 1 = Fiber Mode enabled 4:0 PHYADDR[4:0] 0 = Fiber Mode disabled (STRAP), RW PHY Address: The values of the PHYAD[4:0] pins are latched to this register at power-up/reset. The first PHY address bit transmitted or received is the MSB of the address (bit 4). A station management entity connected to multiple PHY entities must know the appropriate address of each PHY. A PHY address of <00000> that is latched in to the part at power up/reset will cause the Isolate bit of the BMCR (bit 10, register address 00h) to be set. After power up/reset the only way to enable or disable isolate mode is to set or clear the Isolate bit (bit 10) of BMCR (address 00). After power up/reset writing <00000> to bits [4:0] of this register will not cause the part to enter isolate mode. 62 www.national.com 9.0 Electrical Specifications Absolute Maximum Ratings Supply Voltage (VCC) Recommended Operating Conditions -0.5 V to 7.0 V Input Voltage (DCIN) -0.5 V to VCC + 0.5 V Supply voltage (VDD) Output Voltage (DCOUT) -0.5 V to VCC + 0.5 V Ambient Temperature (TA) Storage Temperature o o -65 C to 150 C -50mA 2000 V ECL Signal Output Current ESD Protection Min 4.75 Typ 5.0 Max Units 5.25 V 0 70 X1 Input Frequency Stability -50 +50 (over temperature) X1 Input Duty Cycle Center Frequency (XFC) 35 65 25 o C PPM % MHz All preliminary electrical specifications are based on IEEE 802.3u requirements and internal design considerations. These specifications will not become final until complete verification of the DP83843. Thermal Characteristics* te Max 96 Maximum Case Temperature Maximum Die Temperature 104.7 Theta Junction to Case (Tjc) Units oC oC /W Theta Junction to Ambient (Tja) degrees Celsius/Watt - No Airflow @ 1.0W 42.7 oC /W Theta Junction to Ambient (Tja) degrees Celsius/Watt - 225 LFPM Airflow @ 1.0W 35.3 oC /W Theta Junction to Ambient (Tja) degrees Celsius/Watt - 500 LFPM Airflow @ 1.0W 30.4 oC /W Theta Junction to Ambient (Tja) degrees Celsius/Watt - 900 LFPM Airflow @ 1.0W 26.9 oC /W ol e 1.1 oC O bs *Valid for Phyters with data code 9812 or later, for earlier data codes please contact your National Sales Representative for data. 63 www.national.com 9.0 Electrical Specifications (Continued) 9.1 DC Electrical Specification VIH VIL Pin Types Parameter I I/O I/O, Z Input High Voltage Max Units AN0 and AN1 VCC - 1.0 V X1 VCC - 1.0 V 0.8 V AN0 and AN1 1.0 V X1 1.0 V Input Low Voltage X1 I I/O I/O, Z X1 Pin Unconnected (VCC/2) +0.5 V 10 A -100 A 10 A X2 = N.C. 100 A 0.4 V Input High Current VIN = VCC X2 = N.C. (VCC/2) -0.5 (VCC/2) ol e I I/O I/O, Z IIL Typ V AN0 and AN1 Input Mid Level Voltage IIH Min 2.0 I I/O I/O, Z VIM Conditions te Symbol Input Low Current VIN = GND O, Z I/O I/O, Z Output Low Voltage IOL = 4 mA VOH O, Z I/O I/O, Z Output High Voltage IOL = -4 mA LED SPEED10 Output Low Voltage IOL = 2.5 mA LED SPEED10 Output High Voltage IOL = -2.5 mA I/O, Z O, Z TRI-STATE Leakage VOUT = VCC 10 A I/O, Z O, Z TRI-STATE Leakage VOUT = GND -10 A VOL VOH O IOZ1 bs VOL IOZ2 VCC - 0.5 V 0.4 VCC - 0.5 V V RINdiff TPRD+/- Differential Input Resistance see Test Conditions section 5 6 VTPTD_100 TPTD+/- 100M Transmit Voltage see Test Conditionssection .95 1 VTPTDsym TPTD+/- 100M Transmit see Test Voltage Symmetry Conditions section -2 VTPTD_10 TPTD+/- 10M Transmit Voltage 2.2 CIN1 I CMOS Input Capacitance 8 pF CIN2 I PECL Input Capacitance 10 pF see Test Conditions section 64 2.5 k 1.05 V +2 % 2.8 V www.national.com 9.0 Electrical Specifications (Continued) Symbol Pin Types Parameter Conditions Min Typ Max Units COUT1 O Z CMOS Output Capacitance 8 pF COUT2 O Z PECL Output Capacitance 10 pF SDTHon TPRD+/- 100BASE-TX Signal detect turnon thresh SDTHoff TPRD+/- 100BASE-TX Signal detect turnoff thresh 200 VTH1 TPRD+/- 10BASE-T Receive Threshold 300 585 mV VTH2 TPRD+/- 10BASE-T Receive Low Squelch Threshold 150 300 mV VDIFF FXSD+/-, FXRD+/- PECL Input Voltage Differential VCM FXSD+/-, FXRD+/- PECL Common Mode Voltage see Test Conditions section IINECL FXSD+/-, FXRD+/- PECL Input Current VIN = VOLmax or VOHECL FXTD+/- VOLECL FXTD+/- VOBaui mV diff pk-pk te mV diff pk-pk ol e 300 mV VCC - 2.0 VCC - 0.5 mV -300 300 A PECL Output High VIN = VIHmax Voltage VCC - 1.125 VCC - 0.78 V PECL Output Low VIN = VILmax Voltage VCC - 1.86 VCC - 1.515 V 550 1200 mV VOHmax AUITD+/- Differential Output see Test Voltage Conditions section AUITD+/- Differential Idle Output Voltage Imbalance see Test Conditions section 40 AUIRD+/-, AUICD+/- Differential Squelch Threshold see Test Conditions section 160 300 mV O VDSaui see Test Conditions section bs VODaui 1000 mV Idd100 Supply 100BASE-TX (Full Duplex) see Test Conditions section 135 150 mA Idd10 Supply 10BASE-TX (Full Duplex) see Test Conditions section 100 110 mA IddFX Supply 100BASE-FX (Full Duplex) see Test Conditions section 100 115 mA IddAN Supply Auto-Negotiation see Test Conditions section 100 120 mA IddPD Supply Power Down see Test Conditions section 25 30 mA 65 www.national.com 9.0 Electrical Specifications (Continued) 9.2 CGM Clock Timing X1 IN TX_CLK OUT T2.0.2 Parameter Description T2.0.1 X1 to TX_CLK Delay T2.0.2 TX_CLK Duty Cycle Notes Min Typ Max Units -3 +3 ns 35 65 % Max Units 300 ns ol e 9.3 MII Serial Management AC Timing MDC te T2.0.1 T3.0.1 T3.0.4 bs MDIO (OUTPUT) MDC T3.0.2 O MDIO (INPUT) Parameter Description T3.0.3 VALID DATA Notes Min Typ T3.0.1 MDC to MDIO (Output) Delay Time 0 T3.0.2 MDIO (Input) to MDC Setup Time 10 ns T3.0.3 MDIO (Input) to MDC Hold Time 10 ns T3.0.4 MDC Frequency 2.5 66 MHz www.national.com 9.0 Electrical Specifications (Continued) 9.4 100 Mb/s AC Timing 9.4.1 100 Mb/s MII Transmit Timing TX_CLK T4.1.1 TXD[3:0] TX_EN TX_ER VALID DATA Description T4.1.1 TXD[3:0], TX_EN, TX_ER Data Setup to TX_CLK T4.1.2 TXD[3:0], TX_EN, TX_ER Data Hold from TX_CLK TXD[4:0] Data Setup to TX_CLK TXD[4:0] Data Hold from TX_CLK RX_EN T4.2.1 RX_CLK Min 14 Typ Max Units ns 100 Mb/s Symbol mode 10 ns 100 Mb/s Normal mode -1 ns 100 Mb/s Symbol mode -1 ns ol e 9.4.2 100 Mb/s MII Receive Timing Notes 100 Mb/s Normal mode te Parameter T4.1.2 T4.2.4 T4.2.2 T4.2.3 Parameter T4.2.1 Description T4.2.3 T4.2.4 Notes Min Typ Max Units RX_EN to RX_CLK, RXD[3:0], RX_ER, RX_DV Active All 100 Mb/s modes 15 ns RX_EN to RX_CLK, RXD[3:0], RX_ER, RX_DV TRI-STATE All 100 Mb/s modes 25 ns O T4.2.2 VALID DATA bs RXD[3:0] RX_DV RX_ER RX_CLK to RXD[3:0], RX_DV, RX_ER Delay 100 Mb/s Normal mode 10 30 ns RX_CLK to RXD[4:0], Delay 100 Mb/s Symbol mode 10 30 ns RX_CLK Duty Cycle All 100 Mb/s modes 35 65 % 67 www.national.com 9.0 Electrical Specifications (Continued) 9.4.3 100BASE-TX Transmit Packet Latency Timing TX_CLK TX_EN TXD TPTD+/- T4.3.1 Description (J/K) Notes TX_CLK to TPTD+/- Latency DATA Max Units 100 Mb/s Normal mode 6.0 bits 100 Mb/s Symbol mode 6.0 bits ol e Parameter IDLE te T4.3.1 Min Typ O bs Note: For Normal mode, latency is determined by measuring the time from the first rising edge of TX_CLK occurring after the assertion of TX_EN to the first bit of the "j" code group as output from the TPTD pins. 1 bit time = 10ns in 100 Mb/s mode. For Symbol mode, because TX_EN has no meaning, latency is measured from the first rising edge of TX_CLK occurring after the assertion of a data nibble on the Transmit MII to the first bit (MSB) of that nibble as output from the TPTD pins. 1 bit time = 10 ns in 100 Mb/s mode. 68 www.national.com 9.0 Electrical Specifications (Continued) 9.4.4 100BASE-TX Transmit Packet Deassertion Timing TX_CLK TXD TX_EN Parameter T4.4.1 DATA (T/R) IDLE ol e TPTD+/- te T4.4.1 Description Notes TX_CLK to TPTD+/- Deassertion Min Typ Max Units 100 Mb/s Normal mode 6.0 bits 100 Mb/s Symbol mode 6.0 bits O bs Note: Deassertion is determined by measuring the time from the first rising edge of TX_CLK occurring after the deassertion of TX_EN to the first bit of the "T" code group as output from the TPTD pins. For Symbol mode, because TX_EN has no meaning, Deassertion is measured from the first rising edge of TX_CLK occurring after the deassertion of a data nibble on the Transmit MII to the last bit (LSB) of that nibble when it deasserts on the wire. 1 bit time = 10 ns in 100 Mb/s mode. 69 www.national.com 9.0 Electrical Specifications (Continued) 9.4.5 100BASE-TX Transmit Timing TPTD+/+1 RISE -1 RISE -1 FALL +1 FALL T4.5.2 T4.5.1 ol e TPTD+/EYE PATTERN T4.5.1 T4.5.1 te T4.5.1 T4.5.2 Parameter T4.5.1 Description 100 Mb/s TPTD+/- Rise and Fall Times Notes see Test Conditions section T4.5.2 bs 100 Mb/s Rise/Fall Mismatch 100 Mb/s TPTD+/- Transmit Jitter Min Typ Max Units 3 4 5 ns 500 ps 1.4 ns Note: Normal Mismatch is the difference between the maximum and minimum of all rise and fall times. O Note: Rise and fall times taken at 10% and 90% of the +1 or -1 amplitude. 70 www.national.com 9.0 Electrical Specifications (Continued) 9.4.6 100BASE-TX Receive Packet Latency Timing TPRD+/- IDLE DATA (J/K) T4.6.1 CRS T4.6.2 Parameter te RXD[3:0] RX_DV RX_ER/RXD[4] Description Notes Min Typ Max Units Carrier Sense on Delay 100 Mb/s Normal mode 17.5 bits T4.6.2 Receive Data Latency 100 Mb/s Normal mode 21 bits 100 Mb/s Symbol mode 12 bits ol e T4.6.1 Note: Carrier Sense On Delay is determined by measuring the time from the first bit of the "J" code group to the assertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode. Note: TPRD voltage amplitude is greater than the Signal Detect Turn-On Threshold Value. 9.4.7 100BASE-TX Receive Packet Deassertion Timing DATA IDLE (T/R) bs TPRD+/- T4.7.1 CRS RXD[3:0] RX_DV RX_ER/RXD[4] Description O Parameter T4.7.1 Carrier Sense Off Delay Notes 100 Mb/s Normal mode Min Typ Max Units 21.5 bits Note: Carrier Sense Off Delay is determined by measuring the time from the first bit of the "T" code group to the deassertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode. 71 www.national.com 9.0 Electrical Specifications (Continued) 9.4.8 100BASE-FX Transmit Packet Latency Timing TX_CLK TX_EN TXD FXTD+/- T4.8.1 (J/K) DATA ol e Parameter IDLE te T4.8.1 Description TX_CLK to FXTD+/- Latency Notes Min Typ Max Units 100 Mb/s Normal mode 4.0 bits 100 Mb/s Symbol mode 4.0 bits O bs Note: For Normal mode, Latency is determined by measuring the time from the first rising edge of TX_CLK occurring after the assertion of TX_EN to the first bit of the "j" code group as output from the FXTD pins. For Symbol mode, because TX_EN has no meaning, Latency is measured from the first rising edge of TX_CLK occurring after the assertion of a data nibble on the Transmit MII to the first bit (MSB) of that nibble when it first appears at the FXTD outputs. 72 www.national.com 9.0 Electrical Specifications (Continued) 9.4.9 100BASE-FX Transmit Packet Deassertion Timing TX_CLK TXD TX_EN FXTD+/- Description (T/R) Notes IDLE Max Units 100 Mb/s Normal mode 4.0 bits 100 Mb/s Symbol mode 4.0 bits ol e Parameter T4.9.1 DATA te T4.9.1 TX_CLK to FXTD+/- Deassertion Min Typ Note: Deassertion is determined by measuring the time from the first rising edge of TX_CLK occurring after the deassertion of TX_EN to the first bit of the "T" code group as output from the FXTD pins. For Symbol mode, because TX_EN has no meaning, Deassertion is measured from the first rising edge of TX_CLK occurring after the deassertion of a data nibble on the Transmit MII to the last bit (LSB) of that nibble when it deasserts as output from the FXTD pins. 1 bit time = 10 ns in 100 Mb/s mode. bs 9.4.10 100BASE-FX Receive Packet Latency Timing FXRD+/- IDLE (J/K) DATA T4.10.1 O CRS T4.10.2 RXD[3:0] RX_DV RX_ER/RXD[4] Parameter Description T4.10.1 Carrier Sense On Delay T4.10.2 Receive Data Latency Notes 100 Mb/s Normal mode Min Typ Max Units 17.5 bits 100 Mb/s Normal mode 19 bits 100 Mb/s Symbol mode 19 bits Note: Carrier Sense On Delay is determined by measuring the time from the first bit of the "J" code group to the assertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode. 73 www.national.com 9.0 Electrical Specifications (Continued) 9.4.11 100BASE-FX Receive Packet Deassertion Timing FXRD+/- DATA IDLE (T/R) T4.11.1 CRS RXD[3:0] RX_DV RX_ER/RXD[4] T4.11.1 Description Carrier Sense Off Delay Notes Min Typ 100 Mb/s Normal mode Max Units 21.5 bits te Parameter Note: Carrier Sense Off Delay is determined by measuring the time from the first bit of the "T" code group to the deassertion of Carrier Sense. Note: 1 bit time = 10 ns in 100 Mb/s mode. 9.5 10 Mb/s AC Timing TX_CLK ol e 9.5.12 10 Mb/s MII Transmit Timing T5.12. 1 TXD[3:0] TX_EN TX_ER T5.12.1 Description Notes Min Typ Max Units TXD[3:0], TX_EN Data Setup to TX_CLK 10 Mb/s Nibble mode 25 ns TXD0 Data Setup to TX_CLK 10 Mb/s Serial mode 25 ns TXD[3:0], TX_EN Data Hold from TX_CLK 10 Mb/s Nibble mode -1 ns TXD0 Data Hold from TX_CLK 10 Mb/s Serial mode -1 ns O T5.12.2 VALID DATA bs Parameter T5.12. 2 74 www.national.com 9.0 Electrical Specifications (Continued) 9.5.13 10 Mb/s MII Receive Timing RX_EN T5.13.4 T5.13.1 T5.13. 2 RX_CLK T5.13.3 RXD[3:0] RX_DV RX_ER VALID DATA Description Notes Min Typ te Parameter Max Units T5.13.1 RX_EN to RX_CLK, RXD[3:0], RX_DV Active All 10 Mb/s modes 10 ns T5.13.2 RX_EN to RX_CLK, RXD[3:0], RX_DV TRISTATE 25 ns T5.13.3 RX_CLK to RXD[3:0], RX_DV, RX_ER Delay 10 Mb/s Nibble mode 210 ns RX_CLK to RXD[3:0], RX_DV, RX_ER Delay 10 Mb/s Serial mode 40 60 ns T5.13.4 RX_CLK Duty Cycle 35 65 % All 10 Mb/s modes ol e 190 All 10 Mb/s modes 9.5.14 10BASE-T Transmit Timing (Start of Packet) TX_CLK T5.14. 1 T5.14.2 T5.14. 3 bs TX_EN TXD T5.14.4 O TPTD+/- Parameter Description Notes Min Typ Max Units T5.14.1 Transmit Enable Setup Time from the 10 Mb/s Nibble mode Rising Edge of TX_CLK 10 Mb/s Serial mode 25 ns 25 ns T5.14.2 Transmit Data Setup Time from the Rising Edge of TX_CLK 10 Mb/s Nibble mode 25 ns 10 Mb/s Serial mode 25 ns T5.14.3 Transmit Data Hold Time from the Rising Edge of TX_CLK 10 Mb/s Nibble mode -1 ns 10 Mb/s Serial mode -1 T5.14.4 Transmit Output Delay from the Rising Edge of TX_CLK 10 Mb/s Nibble mode 6.8 bits 10 Mb/s Serial mode 2.5 bits ns Note: 1 bit time = 100 ns in 10 Mb/s mode for both nibble and serial operation. 75 www.national.com 9.0 Electrical Specifications (Continued) 9.5.15 10BASE-T Transmit Timing (End of Packet) T5.15.1 TX_CLK TX_EN 0 T5.15.2 0 TPTD+/- T5.15.1 T5.15.2 Notes Transmit Enable Hold Time from the 10 Mb/s Nibble mode Rising Edge of TX_CLK 10 Mb/s Serial mode Min Typ Max Units -1 ns -1 ns End of Packet High Time 10 Mb/s Nibble mode 250 ns (with `0' ending bit) 10 Mb/s Serial mode 250 ns End of Packet High Time 10 Mb/s Nibble mode 250 ns (with `1' ending bit) 10 Mb/s Serial mode 250 ns O bs T5.15.3 Description T5.15.3 1 ol e Parameter 1 te TPTD+/- 76 www.national.com 9.0 Electrical Specifications (Continued) 9.5.16 10BASE-T Receive Timing (Start of Packet) 1ST SFD BIT DECODED 1 0 1 TPRD+/T5.16.1 CRS T5.16. RX_CLK RXD T5.16. Parameter ol e RX_DV te T5.16.4 Description Notes Min Typ Max Units 1 s T5.16.1 Carrier Sense Turn On Delay (TPRD+/- to CRS) 10 Mb/s Nibble mode 10 Mb/s Serial mode 1 s T5.16.2 Decoder Acquisition Time 10 Mb/s Nibble mode 3.6 s 10 Mb/s Serial mode 3.2 s 10 Mb/s Nibble mode 17.3 bits 10 Mb/s Serial mode 10 bits 10 Mb/s Nibble mode 10 bits 10 Mb/s Serial mode 4.5 bits Max Units Receive Data Latency bs T5.16.3 T5.16.4 SFD Propagation Delay Note: 10BASE-T receive Data Latency is measured from first bit of preamble on the wire to the assertion of RX_DV. Note: 1 bit time = 100 ns in 10 Mb/s mode for both nibble and serial operation. O 9.5.17 10BASE-T Receive Timing (End of Packet) 1 0 IDLE 1 TPRD+/RX_CLK T5.17. 1 CRS Parameter T5.17.1 Description Carrier Sense Turn Off Delay Notes Min Typ 10 Mb/s Nibble mode 1.1 us 10 Mb/s Serial mode 450 ns 77 www.national.com 9.0 Electrical Specifications (Continued) 9.5.18 10 Mb/s AUI Timing 1 0 T5.18. 0 AUITD+/T5.18. T5.18. Parameter Description AUI Transmit Output High Before Idle T5.18.2 AUI Transmit Output Idle Time T5.18.3 AUI Receive End of Packet Hold Time Notes Min Typ Max 200 8000 ol e T5.18.1 te AUIRD+/- 225 Units ns ns ns Note: The worst case for T5.18.1 is data ending in a `0'. 9.5.19 10 Mb/sHeartbeat Timing bs TXE TXC T5.19. T5.19. COL Description O Parameter T5.19.1 T5.19.2 CD Heartbeat Delay CD Heartbeat Duration Notes Min Typ Max Units 10 Mb/s Nibble mode 700 ns 10 Mb/s Serial mode 700 ns 10 Mb/s Nibble mode 700 ns 10 Mb/s Serial mode 700 ns 78 www.national.com 9.0 Electrical Specifications (Continued) 9.5.20 10 Mb/s Jabber Timing TXE T5.20.1 T5.20. TPTD+/- COL T5.20.1 T5.20.2 Description Notes Jabber Activation Time Jabber Deactivation Time Min Typ Max Units 10 Mb/s Nibble mode 26 ms 10 Mb/s Serial mode 26 ms 10 Mb/s Nibble mode 500 ms 10 Mb/s Serial mode 500 ms te Parameter ol e 9.5.21 10BASE-T Normal Link Pulse Timing T5.21.2 bs T5.21.1 Parameter Description Pulse Width T5.21.2 Pulse Period Min Typ Max 100 8 16 Units ns 24 ms O T5.21.1 Notes Note: These specifications represent both transmit and receive timings. 79 www.national.com 9.0 Electrical Specifications (Continued) 9.6 Auto-Negotiation Fast Link Pulse (FLP) Timing T6.21. T6.21. T6.21. 1 T6.21.1 FAST LINK PULSE(S) CLOCK PULSE DATA PULSE CLOCK PULSE T6.21. T6.21.5 FLP BURST Description FLP BURST Notes ol e Parameter te T6.21.4 Clock, Data Pulse Width T6.21.2 Clock Pulse to Clock Pulse Period T6.21.3 Clock Pulse to Data Pulse Period T6.21.4 Number of Pulses in a Burst T6.21.5 Burst Width T6.21.6 FLP Burst to FLP Burst Period Data = 1 bs T6.21.1 Min Typ Max 100 Units ns 139 s 55.5 69.5 s 17 33 # 111 125 2 8 ms 24 ms Max Units 2.7 ns Note: These specifications represent both transmit and receive timings. 9.7 100BASE-X Clock Recovery Module (CRM) Timing NOMINAL WINDOW CENTER O FXRD+/TPRD+/- Parameter T7.21.1 T7.21.1 IDEAL WINDOW RECOGNITION Description Notes CRM Window Recognition Region Min -2.7 Typ Note: The Ideal window recognition region is 4 ns. 80 www.national.com 9.0 Electrical Specifications (Continued) 9.7.22 100BASE-X CRM Acquisition Time FXSD+ OR SD+ INTERNAL T7.22.1 FXRD+/- T7.22.1 Description CRM Acquisition PLL LOCKED Notes 100 Mb/s Min Typ Max Units 250 s te Parameter PLL PRIOR TO LOCK Note: The Clock Generation Module (CGM) must be stable for at least 100 s before the Clock Recovery Module (CRM) can lock to receive data. Note: SD+ internal comes from the internal Signal Detect function block when in 100BASE-TX mode. TPRD +/- ol e 9.7.23 100BASE-TX Signal Detect Timing T7.23. T7.23.2 bs SD+ INTERNAL Parameter Description Notes Min Typ Max Units T7.23.1 SD Internal Turn-on Time 1 ms T7.23.2 SD Internal Turn-off Time 300 s Note: The SD internal signal is available as an external signal in Symbol mode. O Note: The signal amplitude at TPRD +/- is TP-PMD compliant. 81 www.national.com 9.0 Electrical Specifications (Continued) 9.8 Reset Timing VCC T8.23. T8.23. T8.23. HARDWARE RESET (OPTION #1) te HARDWARE RESET (OPTION #2) 32 CLOCKS ol e MDC T8.23. LATCH-IN OF HARDWARE CONFIGURATION PINS T8.23.5 INPUT OUTPUT DUAL FUNCTION PINS BECOME ENABLED AS OUTPUTS Description bs Parameter Notes Min Typ Max Units 500 s 1 s 500 s Internal Reset Time T8.23.2 Hardware RESET Pulse Width T8.23.3 Post Reset Stabilization time MDIO is pulled high for 32 bit serial manprior to MDC preamble for reg- agement initialization ister accesses T8.23.4 Hardware Configuration Latch- Hardware Configuration Pins are dein Time from the Deassertion of scribed in the Pin Description section Reset (either soft or hard) 800 ns Hardware Configuration pins transition to output drivers 800 ns O T8.23.1 T8.23.5 It is important to choose pull-up and/or pull-down resistors for each of the hardware configuration pins that provide fast RC time constants in order to latch-in the proper value prior to the pin transitioning to an output driver Note: Software Reset should be initiated no sooner then 500 s after power-up or the deassertion of hardware reset. Note: It is important to choose pull-up and/or pull-down resistors for each of the hardware configuration pins that provide fast RC time constants in order to latch-in the proper value prior to the pin transitioning to an output driver. Note: The timing for Hardware Reset Option 2 is equal to parameter T1 plus parameter T2 (501 s total). 82 www.national.com 9.0 Electrical Specifications (Continued) 9.9 Loopback Timing TX_CLK TX_EN CRS T9.23.1 RX_DV bs RXD[3:0] ol e RX_CLK te TXD[3:0] Parameter T9.23.1 Description TX_EN to RX_DV Loopback Notes Min Typ Max Units 100 Mb/s 240 ns 10 Mb/s Serial mode 650 ns 10 Mb/s Nibble mode 2 s Note: Due to the nature of the descrambler function, all 100BASE-X Loopback modes will cause an initial "dead-time" of up to 550 s during which time no data will be present at the receive MII outputs. The 100BASE-X timing specified is based on device delays after the initial 550s "dead-time". O Note: During loopback (all modes) both the TPTD or FXTD/AUITD outputs remain inactive by default. 83 www.national.com 9.0 Electrical Specifications (Continued) 9.10 Isolation Timing CLEAR BIT 10 OF BMCR (RETURN TO NORMAL OPERATION FROM ISOLATE MODE) T10.23.1 H/W OR S/W RESET (WITH PHYAD 00000) T10.23.2 MODE Parameter Description From software clear of bit 10 in the BMCR register to the transition from Isolate to Normal Mode T10.23.2 From Deassertion of S/W or H/W Reset to transition from Isolate to Normal mode Notes Min Typ Max Units 100 s 500 s O bs ol e T10.23.1 NORMAL te ISOLATE 84 www.national.com 10.0 Test Conditions of this load is 50 pF. The diagram in Figure 28 illustrates the test configuration. This section contains information relating to the specific test environments, including stimulus and loading parameters, for the DP83843. These test conditions are categorized in the following subsections by each type of pin/interface including: It should be noted that the current source and sink limits are set to 4.0 mA when testing/loading the MII output pins. The current source and sink limits are set to 2.5 mA when testing/loading the LED output pins. -- FXTD/AUITD+/- Outputs sourcing AUI -- FXTD/AUITD+/- Outputs sourcing 100BASE-FX 10.4 TPTD+/- Outputs (sourcing 10BASE-T) -- CMOS Outputs i.e. MII and LEDs When configured for 10BASE-T operation, these differen-- TPTD+/- Outputs sourcing 100BASE-TX tial outputs source Manchester encoded binary data at 10BASE-T logic levels. These outputs are loaded as illus-- TPTD+/- Outputs sourcing 10BASE-T trated in Figure 29. Note that the transmit amplitude meaAdditionally, testing conditions for Idd measurements are surements are made across the secondary of the transmit included. transformer as specified by the IEEE 802.3 specification. 10.1 FXTD/AUITD+/- Outputs (sourcing AUI levels) 10.5 TPTD+/- Outputs (sourcing 100BASE-TX) ol e te When configured for 100BASE-TX operation, these differWhen configured for AUI operation, these differential out- ential outputs source scrambled 125Mb/s data at MLT-3 puts source Manchester encoded 10 Mb/s data at AUI logic logic levels. These outputs are loaded as illustrated in levels. These outputs are loaded as illustrated in Figure 26. Figure 29. Note that the transmit amplitude and rise/fall time measurements are made across the secondary of the 10.2 FXTD/AUITD+/- Outputs (sourcing PECL) transmit transformer as specified by the IEEE 802.3u specWhen configured for 100BASE-FX operation, these differ- ification. ential outputs source unscrambled 125 Mb/s data at PECL logic levels. These outputs are loaded as illustrated in 10.6 Idd Measurement Conditions Figure 27. The DP83843 PHYTER is currently tested for total device Idd under four operational modes: 10.3 CMOS Outputs (MII and LED) Each of the MII and LED outputs are loaded with a con- -- 100BASE-TX Full Duplex (max packet length / min IPG) trolled current source to either ground or VCC for testing -- 10BASE-TX Half Duplex (max packet length / min IPG) Voh, Vol, and AC parametrics. The associated capacitance -- 100BASE-FX Full Duplex (max packet length / min IPG) AUIRD AUICD bs AUITD 200 100H TRANSFORMER O 200 39 39 DB-15 CONNECTOR 39 39 78 .01F .01F TYPICAL AUI TRANSMIT LOAD 27H Figure 26. AUI Test Load 85 www.national.com 10.0 Test Conditions (Continued) AUITD/FXTD+ DP83843 PHYTER AUITD/FXTD- 50 te 50 VTT = VCC - 2.2V VTT VTT Figure 27. 100BASE-FX Test Load CURRENT SOUR ol e VCC 50pF DP83843 PHYTER CMOS OUTPUT bs 50pF CURRENT SINK GND O Figure 28. CMOS Output Test Load TPTD+ 100 DP83843 PHYTER 100 TPTD10/100 AC COUPLING TRANSFORMER Figure 29. 10/100 Twisted Pair Load (zero meters) 86 www.national.com ol e te DP83843 PHYTER 11.0 Package Dimensions inches (millimeters) unless otherwise noted O bs Molded Plastic Quad Flat Package Order Number DP83843BVJE NC Package Number VJE80A LIFE SUPPORT POLICY NATIONAL'S PRODUCTS ARE NOT AUTHORIZED FOR USE AS CRITICAL COMPONENTS IN LIFE SUPPORT DEVICES OR SYSTEMS WITHOUT THE EXPRESS WRITTEN APPROVAL OF THE PRESIDENT OF NATIONAL SEMICONDUCTOR CORPORATION. As used herein: 1. Life support devices or systems are devices or systems which, (a) are intended for surgical implant into the body, or (b) support or sustain life, and whose failure to perform, when properly used in accordance with instructions for use provided in the labeling, can be reasonably expected to result in a significant injury to the user. National Semiconductor Corporation Tel: 1-800-272-9959 Fax: 1-800-737-7018 Email: support@nsc.com National Semiconductor Europe Fax: (+49) 0-180-530 85 86 Email: europe.support@nsc.com Deutsch Tel: (+49) 0-180-530 85 85 English Tel: (+49) 0-180-532 78 32 2. A critical component is any component of a life support device or system whose failure to perform can be reasonably expected to cause the failure of the life support device or system, or to affect its safety or effectiveness. National Semiconductor Asia Pacific Customer Response Group Tel: 65-254-4466 Fax: 65-250-4466 Email: sea.support@nsc.com National Semiconductor Japan Ltd. Tel: 81-3-5620-6175 Fax: 81-3-5620-6179 www.national.com National does not assume any responsibility for use of any circuitry described, no circuit patent licenses are implied and National reserves the right at any time without notice to change said circuitry and specifications. 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