PIC16C55X EPROM-Based 8-Bit CMOS Microcontrollers Devices included in this data sheet: Pin Diagram Referred to collectively as PIC16C55X. PDIP, SOIC, Windowed CERDIP High Performance RISC CPU: * Only 35 instructions to learn * All single-cycle instructions (200 ns), except for program branches which are two-cycle * Operating speed: - DC - 20 MHz clock input - DC - 200 ns instruction cycle Device Program Memory Data Memory PIC16C554 512 80 PIC16C558 2K 128 * * * * *1 2 3 4 5 6 7 8 9 18 17 16 15 14 13 12 11 10 RA1 RA0 OSC1/CLKIN OSC2/CLKOUT VDD RB7 RB6 RB5 RB4 PIC16C55X RA2 RA3 RA4/T0CKI MCLR/ VPP VSS RB0/INT RB1 RB2 RB3 PIC16C55X * PIC16C554 * PIC16C558 20 19 18 17 16 15 14 13 12 11 RA1 RA0 OSC1/CLKIN OSC2/CLKOUT VDD VDD RB7 RB6 RB5 RB4 SSOP RA2 RA3 RA4/T0CKI MCLR/ VPP VSS VSS RB0/INT RB1 RB2 RB3 Interrupt capability 16 special function hardware registers 8-level deep hardware stack Direct, Indirect and Relative addressing modes *1 2 3 4 5 6 7 8 9 10 Peripheral Features: * 13 I/O pins with individual direction control * High current sink/source for direct LED drive * Timer0: 8-bit timer/counter with 8-bit programmable prescaler Special Microcontroller Features: * Power-on Reset (POR) * Power-up Timer (PWRT) and Oscillator Start-up Timer (OST) * Watchdog Timer (WDT) with its own on-chip RC oscillator for reliable operation 1998 Microchip Technology Inc. Special Microcontroller Features (cont'd) * * * * * Programmable code protection Power saving SLEEP mode Selectable oscillator options Serial in-circuit programming (via two pins) Four user programmable ID locations CMOS Technology: * Low-power, high-speed CMOS EPROM technology * Fully static design * Wide operating voltage range - 2.5V to 5.5V * Commercial, industrial and extended temperature range * Low power consumption - < 2.0 mA @ 5.0V, 4.0 MHz - 15 A typical @ 3.0V, 32 kHz - < 1.0 A typical standby current @ 3.0V Preliminary DS40143C-page 1 PIC16C55X Device Differences Device Voltage Range Oscillator Process Technology (Microns) PIC16C554 2.5 - 5.5 See Note 1 0.9 PIC16C558 2.5 - 5.5 See Note 1 0.9 Note 1: If you change from this device to another device, please verify oscillator characteristics in your application. DS40143C-page 2 Preliminary 1998 Microchip Technology Inc. PIC16C55X Table of Contents 1.0 General Description......................................................................................................................................................................5 2.0 PIC16C55X Device Varieties .......................................................................................................................................................7 3.0 Architectural Overview .................................................................................................................................................................9 4.0 Memory Organization ................................................................................................................................................................ 13 5.0 I/O Ports .................................................................................................................................................................................... 23 6.0 Timer0 Module .......................................................................................................................................................................... 29 7.0 Special Features of the CPU..................................................................................................................................................... 35 8.0 Instruction Set Summary ........................................................................................................................................................... 51 9.0 Development Support................................................................................................................................................................ 63 10.0 Electrical Specifications............................................................................................................................................................. 69 11.0 Packaging Information............................................................................................................................................................... 81 Appendix A: Enhancements............................................................................................................................................................ 87 Appendix B: Compatibility ............................................................................................................................................................... 87 INDEX .................................................................................................................................................................................................. 89 PIC16C55X Product Identification System .......................................................................................................................................... 93 To Our Valued Customers Most Current Data Sheet To obtain the most up-to-date version of this data sheet, please check our Worldwide Web site at: http://www.microchip.com You can determine the version of a data sheet by examining its literature number found on the bottom outside corner of any page. The last character of the literature number is the version number. e.g., DS30000A is version A of document DS30000. Errata An errata sheet may exist for current devices, describing minor operational differences (from the data sheet) and recommended workarounds. As device/documentation issues become known to us, we will publish an errata sheet. The errata will specify the revision of silicon and revision of document to which it applies. To determine if an errata sheet exists for a particular device, please check with one of the following: * Microchip's Worldwide Web site; http://www.microchip.com * Your local Microchip sales office (see last page) * The Microchip Corporate Literature Center; U.S. FAX: (602) 786-7277 When contacting a sales office or the literature center, please specify which device, revision of silicon and data sheet (include literature number) you are using. Corrections to this Data Sheet We constantly strive to improve the quality of all our products and documentation. We have spent a great deal of time to ensure that this document is correct. However, we realize that we may have missed a few things. If you find any information that is missing or appears in error, please: * Fill out and mail in the reader response form in the back of this data sheet. * E-mail us at webmaster@microchip.com. We appreciate your assistance in making this a better document. 1998 Microchip Technology Inc. Preliminary DS40143C-page 3 PIC16C55X NOTES: DS40143C-page 4 Preliminary 1998 Microchip Technology Inc. PIC16C55X 1.0 GENERAL DESCRIPTION The PIC16C55X are 18 and 20-Pin EPROM-based members of the versatile PIC16CXX family of low-cost, high-performance, CMOS, fully-static, 8-bit microcontrollers. All PICmicro(R) microcontrollers employ an advanced RISC architecture. The PIC16C55X have enhanced core features, eight-level deep stack, and multiple internal and external interrupt sources. The separate instruction and data buses of the Harvard architecture allow a 14-bit wide instruction word with the separate 8-bit wide data. The two-stage instruction pipeline allows all instructions to execute in a single-cycle, except for program branches (which require two cycles). A total of 35 instructions (reduced instruction set) are available. Additionally, a large register set gives some of the architectural innovations used to achieve a very high performance. PIC16C55X microcontrollers typically achieve a 2:1 code compression and a 4:1 speed improvement over other 8-bit microcontrollers in their class. The PIC16C554 has 80 bytes of RAM. The PIC16C558 has 128 bytes of RAM. Each device has 13 I/O pins and an 8-bit timer/counter with an 8-bit programmable prescaler. PIC16C55X devices have special features to reduce external components, thus reducing cost, enhancing system reliability and reducing power consumption. There are four oscillator options, of which the single pin RC oscillator provides a low-cost solution, the LP oscillator minimizes power consumption, XT is a standard crystal, and the HS is for High Speed crystals. The SLEEP (power-down) mode offers power saving. The user can wake up the chip from SLEEP through several external and internal interrupts and reset. 1998 Microchip Technology Inc. A highly reliable Watchdog Timer with its own on-chip RC oscillator provides protection against software lock-up. A UV-erasable CERDIP-packaged version is ideal for code development while the cost-effective One-Time Programmable (OTP) version is suitable for production in any volume. Table 1-1 shows the features of the PIC16C55X mid-range microcontroller families. A simplified block diagram of the PIC16C55X is shown in Figure 3-1. The PIC16C55X series fit perfectly in applications ranging from motor control to low-power remote sensors. The EPROM technology makes customization of application programs (detection levels, pulse generation, timers, etc.) extremely fast and convenient. The small footprint packages make this microcontroller series perfect for all applications with space limitations. Low-cost, low-power, high-performance, ease of use and I/O flexibility make the PIC16C55X very versatile. 1.1 Family and Upward Compatibility Those users familiar with the PIC16C5X family of microcontrollers will realize that this is an enhanced version of the PIC16C5X architecture. Please refer to Appendix A for a detailed list of enhancements. Code written for PIC16C5X can be easily ported to PIC16C55X family of devices (Appendix B). The PIC16C55X family fills the niche for users wanting to migrate up from the PIC16C5X family and not needing various peripheral features of other members of the PIC16XX mid-range microcontroller family. 1.2 Development Support The PIC16C55X family is supported by a full-featured macro assembler, a software simulator, an in-circuit emulator, a low-cost development programmer and a full-featured programmer. A "C" compiler and fuzzy logic support tools are also available. Preliminary DS40143C-page 5 PIC16C55X TABLE 1-1: PIC16C55X FAMILY OF DEVICES PIC16C558 PIC16C554 Clock Memory Peripherals Features Maximum Frequency of Operation (MHz) 20 20 EPROM Program Memory (x14 words) 512 2K Data Memory (bytes) 80 128 Timer Module(s) TMR0 TMR0 Interrupt Sources 3 3 I/O Pins 13 13 Voltage Range (Volts) 2.5-5.5 2.5-5.5 Brown-out Reset -- -- Packages 18-pin DIP, SOIC; 20-pin SSOP 18-pin DIP, SOIC; 20-pin SSOP All PICmicro(R) Family devices have Power-on Reset, selectable Watchdog Timer, selectable code protect and high I/O current capability. All PIC16C55X Family devices use serial programming with clock pin RB6 and data pin RB7. DS40143C-page 6 Preliminary 1998 Microchip Technology Inc. PIC16C55X 2.0 PIC16C55X DEVICE VARIETIES A variety of frequency ranges and packaging options are available. Depending on application and production requirements the proper device option can be selected using the information in the PIC16C55X Product Identification System section at the end of this data sheet. When placing orders, please use this page of the data sheet to specify the correct part number. 2.1 UV Erasable Devices The UV erasable version, offered in CERDIP package is optimal for prototype development and pilot programs. This version can be erased and reprogrammed to any of the oscillator modes. Microchip's PICSTART and PROMATE programmers both support programming of the PIC16C55X. 2.2 One-Time-Programmable (OTP) Devices The availability of OTP devices is especially useful for customers who need the flexibility for frequent code updates and small volume applications. In addition to the program memory, the configuration bits must also be programmed. 1998 Microchip Technology Inc. 2.3 Quick-Turnaround-Production (QTP) Devices Microchip offers a QTP Programming Service for factory production orders. This service is made available for users who choose not to program a medium to high quantity of units and whose code patterns have stabilized. The devices are identical to the OTP devices but with all EPROM locations and configuration options already programmed by the factory. Certain code and prototype verification procedures apply before production shipments are available. Please contact your Microchip Technology sales office for more details. 2.4 Serialized Quick-Turnaround-Production (SQTPSM) Devices Microchip offers a unique programming service where a few user-defined locations in each device are programmed with different serial numbers. The serial numbers may be random, pseudo-random or sequential. Serial programming allows each device to have a unique number which can serve as an entry-code, password or ID number. Preliminary DS40143C-page 7 PIC16C55X NOTES: DS40143C-page 8 Preliminary 1998 Microchip Technology Inc. PIC16C55X 3.0 ARCHITECTURAL OVERVIEW The high performance of the PIC16C55X family can be attributed to a number of architectural features commonly found in RISC microprocessors. To begin with, the PIC16C55X uses a Harvard architecture, in which, program and data are accessed from separate memories using separate busses. This improves bandwidth over traditional von Neumann architecture where program and data are fetched from the same memory. Separating program and data memory further allows instructions to be sized differently than 8-bit wide data words. Instruction opcodes are 14-bits wide making it possible to have all single word instructions. A 14-bit wide program memory access bus fetches a 14-bit instruction in a single cycle. A two-stage pipeline overlaps fetch and execution of instructions. Consequently, all instructions (35) execute in a single-cycle (200 ns @ 20 MHz) except for program branches. The table below lists the memory (EEPROM and ROM). Device Program Memory Data Memory PIC16C554 512 80 PIC16C558 2K 128 The PIC16C55X devices contain an 8-bit ALU and working register. The ALU is a general purpose arithmetic unit. It performs arithmetic and Boolean functions between data in the working register and any register file. The ALU is 8-bits wide and capable of addition, subtraction, shift and logical operations. Unless otherwise mentioned, arithmetic operations are two's complement in nature. In two-operand instructions, typically one operand is the working register (W register). The other operand is a file register or an immediate constant. In single operand instructions, the operand is either the W register or a file register. The W register is an 8-bit working register used for ALU operations. It is not an addressable register. Depending on the instruction executed, the ALU may affect the values of the Carry (C), Digit Carry (DC), and Zero (Z) bits in the STATUS register. The C and DC bits operate as a Borrow and Digit Borrow out bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for examples. A simplified block diagram is shown in Figure 3-1, with a description of the device pins in Table 3-1. The PIC16C554 addresses 512 x 14 on-chip program memory. The PIC16C558 addresses 2K x 14 program memory. All program memory is internal. The PIC16C55X can directly or indirectly address its register files or data memory. All special function registers including the program counter are mapped into the data memory. The PIC16C55X have an orthogonal (symmetrical) instruction set that makes it possible to carry out any operation on any register using any addressing mode. This symmetrical nature and lack of `special optimal situations' make programming with the PIC16C55X simple yet efficient. In addition, the learning curve is reduced significantly. 1998 Microchip Technology Inc. Preliminary DS40143C-page 9 PIC16C55X FIGURE 3-1: BLOCK DIAGRAM Program Memory Device PIC16C554 PIC16C558 512 x 14 2K x 14 Data Memory (RAM) 80 x 8 128 x 8 EPROM 13 Program Memory 512 x 14 to 2K x 14 Program Bus PORTA RA0 RA1 RA2 RA3 RAM File Registers 80 x 8 to 128 x 8 8 Level Stack (13-bit) 14 8 Data Bus Program Counter RAM Addr(1) RA4/T0CKI PORTB 8 Addr MUX Instruction reg Direct Addr 7 8 Indirect Addr FSR reg RB0/INT RB7:RB1 STATUS reg 8 3 Power-up Timer Instruction Decode & Control Timing Generation Oscillator Start-up Timer MUX ALU Power-on Reset 8 Watchdog Timer W reg OSC1/CLKIN OSC2/CLKOUT Timer0 MCLR VDD, VSS Note 1: Higher order bits are from the status register. DS40143C-page 10 Preliminary 1998 Microchip Technology Inc. PIC16C55X TABLE 3-1: Name PIC16C55X PINOUT DESCRIPTION DIP SOIC Pin # SSOP Pin # I/O/P Type Buffer Type Description OSC1/CLKIN 16 18 I ST/CMOS Oscillator crystal input/external clock source input. OSC2/CLKOUT 15 17 O -- Oscillator crystal output. Connects to crystal or resonator in crystal oscillator mode. In RC mode, OSC2 pin outputs CLKOUT which has 1/4 the frequency of OSC1, and denotes the instruction cycle rate. MCLR/VPP 4 4 I/P ST Master clear (reset) input/programming voltage input. This pin is an active low reset to the device. RA0 17 19 I/O ST Bi-directional I/O port RA1 18 20 I/O ST Bi-directional I/O port RA2 1 1 I/O ST Bi-directional I/O port RA3 2 2 I/O ST Bi-directional I/O port RA4/T0CKI 3 3 I/O ST Bi-directional I/O port or external clock input for TMR0. Output is open drain type. RB0/INT 6 7 I/O TTL/ST(1) Bi-directional I/O port can be software programmed for internal weak pull-up. RB0/INT can also be selected as an external interrupt pin. RB1 7 8 I/O TTL Bi-directional I/O port can be software programmed for internal weak pull-up. RB2 8 9 I/O TTL Bi-directional I/O port can be software programmed for internal weak pull-up. RB3 9 10 I/O TTL Bi-directional I/O port can be software programmed for internal weak pull-up. RB4 10 11 I/O TTL Bi-directional I/O port can be software programmed for internal weak pull-up. Interrupt on change pin. RB5 11 12 I/O TTL Bi-directional I/O port can be software programmed for internal weak pull-up. Interrupt on change pin. RB6 12 13 I/O TTL/ST(2) Bi-directional I/O port can be software programmed for internal weak pull-up. Interrupt on change pin. Serial programming clock. RB7 13 14 I/O TTL/ST(2) Bi-directional I/O port can be software programmed for internal weak pull-up. Interrupt on change pin. Serial programming data. VSS 5 5,6 P -- Ground reference for logic and I/O pins. VDD 14 15,16 P -- Positive supply for logic and I/O pins. Legend: O = output I/O = input/output P = power -- = Not used I = Input ST = Schmitt Trigger input TTL = TTL input Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt. Note 2: This buffer is a Schmitt Trigger input when used in serial programming mode. 1998 Microchip Technology Inc. Preliminary DS40143C-page 11 PIC16C55X Clocking Scheme/Instruction Cycle 3.1 3.2 The clock input (OSC1/CLKIN pin) is internally divided by four to generate four non-overlapping quadrature clocks namely Q1, Q2, Q3 and Q4. Internally, the program counter (PC) is incremented every Q1, the instruction is fetched from the program memory and latched into the instruction register in Q4. The instruction is decoded and executed during the following Q1 through Q4. The clocks and instruction execution flow are shown in Figure 3-2. Instruction Flow/Pipelining An "Instruction Cycle" consists of four Q cycles (Q1, Q2, Q3 and Q4). The instruction fetch and execute are pipelined such that fetch takes one instruction cycle while decode and execute takes another instruction cycle. However, due to the pipelining, each instruction effectively executes in one cycle. If an instruction causes the program counter to change (e.g., GOTO) then two cycles are required to complete the instruction (Example 3-1). A fetch cycle begins with the program counter (PC) incrementing in Q1. In the execution cycle, the fetched instruction is latched into the "Instruction Register (IR)" in cycle Q1. This instruction is then decoded and executed during the Q2, Q3, and Q4 cycles. Data memory is read during Q2 (operand read) and written during Q4 (destination write). FIGURE 3-2: CLOCK/INSTRUCTION CYCLE Q1 Q2 Q3 Q4 Q2 Q1 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 Q1 Q2 Internal phase clock Q3 Q4 PC OSC2/CLKOUT (RC mode) EXAMPLE 3-1: PC PC+1 Fetch INST (PC) Execute INST (PC-1) PC+2 Fetch INST (PC+1) Execute INST (PC) Fetch INST (PC+2) Execute INST (PC+1) INSTRUCTION PIPELINE FLOW 1. MOVLW 55h 2. MOVWF PORTB 3. CALL SUB_1 4. BSF PORTA, BIT3 Fetch 1 Execute 1 Fetch 2 Execute 2 Fetch 3 Execute 3 Fetch 4 Flush Fetch SUB_1 Execute SUB_1 All instructions are single cycle, except for any program branches. These take two cycles since the fetch instruction is "flushed" from the pipeline while the new instruction is being fetched and then executed. DS40143C-page 12 Preliminary 1998 Microchip Technology Inc. PIC16C55X 4.0 MEMORY ORGANIZATION 4.1 Program Memory Organization FIGURE 4-2: The PIC16C55X has a 13-bit program counter capable of addressing an 8K x 14 program memory space. Only the first 512 x 14 (0000h - 01FFh) for the PIC16C554 and 2K x 14 (0000h - 07FFh) for the PIC16C558 are physically implemented. Accessing a location above these boundaries will cause a wrap-around within the first 512 x 14 space PIC16C554 or 2K x 14 space PIC16C558. The reset vector is at 0000h and the interrupt vector is at 0004h (Figure 4-1, Figure 4-2). FIGURE 4-1: PROGRAM MEMORY MAP AND STACK FOR THE PIC16C558 PC<12:0> CALL, RETURN RETFIE, RETLW 13 Stack Level 1 Stack Level 2 Stack Level 8 PROGRAM MEMORY MAP AND STACK FOR THE PIC16C554 Reset Vector 000h Interrupt Vector 0004 0005 PC<12:0> CALL, RETURN RETFIE, RETLW 13 On-chip Program Memory Stack Level 1 Stack Level 2 07FFh 0800h Stack Level 8 1FFFh Reset Vector 000h 4.2 Interrupt Vector 0004 0005 On-chip Program Memory 01FFh 0200h 1FFFh Data Memory Organization The data memory (Figure 4-3 and Figure 4-4) is partitioned into two Banks which contain the general purpose registers and the special function registers. Bank 0 is selected when the RP0 bit (STATUS <5>) is cleared. Bank 1 is selected when the RP0 bit is set. The Special Function Registers are located in the first 32 locations of each Bank. Register locations 20-6Fh (Bank0) on the PIC16C554 and 20-7Fh (Bank0) and A0-BFh (Bank1) on the PIC16C558 are general purpose registers implemented as static RAM. Some special purpose registers are mapped in Bank 1. 4.2.1 GENERAL PURPOSE REGISTER FILE The register file is organized as 80 x 8 in the PIC16C554 and 128 x 8 in the PIC16C558. Each can be accessed either directly or indirectly through the File Select Register, FSR (Section 4.4). 1998 Microchip Technology Inc. Preliminary DS40143C-page 13 PIC16C55X FIGURE 4-3: DATA MEMORY MAP FOR THE PIC16C554 File Address 00h 01h 02h 03h 04h 05h 06h 07h 08h 09h 0Ah 0Bh 0Ch 0Dh 0Eh 0Fh 10h 11h 12h 13h 14h 15h 16h 17h 18h 19h 1Ah 1Bh 1Ch 1Dh 1Eh 1Fh 20h 6Fh INDF(1) TMR0 PCL STATUS FSR PORTA PORTB INDF(1) OPTION PCL STATUS FSR TRISA TRISB PCLATH INTCON PCLATH INTCON PCON FIGURE 4-4: File Address File Address 80h 81h 82h 83h 84h 85h 86h 87h 88h 89h 8Ah 8Bh 8Ch 8Dh 8Eh 8Fh 90h 91h 92h 93h 94h 95h 96h 97h 98h 99h 9Ah 9Bh 9Ch 9Dh 9Eh 9Fh 00h 01h 02h 03h 04h 05h 06h 07h 08h 09h 0Ah 0Bh 0Ch 0Dh 0Eh 0Fh 10h 11h 12h 13h 14h 15h 16h 17h 18h 19h 1Ah 1Bh 1Ch 1Dh 1Eh 1Fh 20h A0h General Purpose Register DATA MEMORY MAP FOR THE PIC16C558 File Address INDF(1) TMR0 PCL STATUS FSR PORTA PORTB INDF(1) OPTION PCL STATUS FSR TRISA TRISB PCLATH INTCON PCLATH INTCON PCON General Purpose Register General Purpose Register 70h 7Fh 80h 81h 82h 83h 84h 85h 86h 87h 88h 89h 8Ah 8Bh 8Ch 8Dh 8Eh 8Fh 90h 91h 92h 93h 94h 95h 96h 97h 98h 99h 9Ah 9Bh 9Ch 9Dh 9Eh 9Fh A0h BFh C0h FFh Bank 0 Unimplemented data memory locations, read as '0'. Note 1: Not a physical register. DS40143C-page 14 7Fh Bank 1 FFh Bank 0 Bank 1 Unimplemented data memory locations, read as '0'. Note 1: Not a physical register. Preliminary 1998 Microchip Technology Inc. PIC16C55X 4.2.2 The special function registers can be classified into two sets (core and peripheral). The special function registers associated with the "core" functions are described in this section. Those related to the operation of the peripheral features are described in the section of that peripheral feature. SPECIAL FUNCTION REGISTERS The Special Function Registers are registers used by the CPU and peripheral functions for controlling the desired operation of the device (Table 4-1). These registers are static RAM. TABLE 4-1: SPECIAL REGISTERS FOR THE PIC16C55X Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR Reset Value on all other resets(1) xxxx xxxx xxxx xxxx Bank 0 00h INDF Addressing this location uses contents of FSR to address data memory (not a physical register) 01h TMR0 Timer0 Module's Register xxxx xxxx uuuu uuuu 02h PCL Program Counter's (PC) Least Significant Byte 0000 0000 0000 0000 03h STATUS 0001 1xxx 000q quuu 04h FSR 05h PORTA -- -- -- RA4 RA3 RA2 RA1 RB7 RB6 RB5 RB4 RB3 RB2 RB1 IRP(2) RP1(2) RP0 TO PD Z DC C Indirect data memory address pointer xxxx xxxx uuuu uuuu RA0 ---x xxxx ---u uuuu RB0 06h PORTB xxxx xxxx uuuu uuuu 07h Unimplemented -- -- 08h Unimplemented -- -- 09h Unimplemented -- -- 0Ah PCLATH -- -- -- ---0 0000 ---0 0000 0Bh INTCON GIE (3) T0IE 0000 000x 0000 000u 0Ch Unimplemented -- -- 0Dh-1Eh Unimplemented -- -- 1Fh -- -- xxxx xxxx xxxx xxxx Write buffer for upper 5 bits of program counter INTE RBIE T0IF INTF RBIF Unimplemented Bank 1 Addressing this location uses contents of FSR to address data memory (not a physical register) 80h INDF 81h OPTION 82h PCL 83h STATUS 84h FSR 85h TRISA -- -- -- TRISA4 TRISA3 TRISA2 TRISA1 86h TRISB TRISB7 TRISB6 TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 87h Unimplemented 88h RBPU INTEDG T0CS T0SE PSA PS2 PS1 PS0 Program Counter's (PC) Least Significant Byte -- -- RP0 TO PD Z DC C Indirect data memory address pointer 1111 1111 1111 1111 0000 0000 0000 0000 0001 1xxx 000q quuu xxxx xxxx uuuu uuuu TRISA0 ---1 1111 ---1 1111 TRISB0 1111 1111 1111 1111 -- -- Unimplemented -- -- 89h Unimplemented -- -- 8Ah PCLATH -- -- -- ---0 0000 ---0 0000 8Bh INTCON GIE (3) T0IE 0000 000x 0000 000u 8Ch Unimplemented -- -- 8Dh Unimplemented -- -- 8Eh PCON ---- --0- ---- --u- 8Fh-9Eh Unimplemented -- -- 9Fh Unimplemented -- -- -- -- -- Write buffer for upper 5 bits of program counter INTE -- RBIE -- T0IF -- INTF POR RBIF -- Legend: -- = Unimplemented locations read as `0', u = unchanged, x = unknown, q = value depends on condition, shaded = unimplemented Note 1: Other (non power-up) resets include MCLR reset and Watchdog Timer reset during normal operation. Note 2: IRP & RP1bits are reserved, always maintain these bits clear. Note 3: Bit 6 of INTCON register is reserved for future use. Always maintain this bit as clear. 1998 Microchip Technology Inc. Preliminary DS40143C-page 15 PIC16C55X 4.2.2.1 It is recommended, therefore, that only BCF, BSF, SWAPF and MOVWF instructions be used to alter the STATUS register because these instructions do not affect any status bits. For other instructions, not affecting any status bits, see the "Instruction Set Summary". STATUS REGISTER The STATUS register, shown in Figure 4-5, contains the arithmetic status of the ALU, the RESET status and the bank select bits for data memory. The STATUS register can be the destination for any instruction, like any other register. If the STATUS register is the destination for an instruction that affects the Z, DC or C bits, then the write to these three bits is disabled. These bits are set or cleared according to the device logic. Furthermore, the TO and PD bits are not writable. Therefore, the result of an instruction with the STATUS register as the destination may be different than intended. Note 1: The IRP and RP1 bits (STATUS<7:6>) are not used by the PIC16C55X and should be programmed as '0'. Use of these bits as general purpose R/W bits is NOT recommended, since this may affect upward compatibility with future products. Note 2: The C and DC bits operate as a Borrow and Digit Borrow out bit, respectively, in subtraction. See the SUBLW and SUBWF instructions for examples. For example, CLRF STATUS will clear the upper-three bits and set the Z bit. This leaves the status register as 000uu1uu (where u = unchanged). FIGURE 4-5: STATUS REGISTER (ADDRESS 03H OR 83H) Reserved Reserved IRP RP1 bit7 bit 7: R/W-0 RP0 R-1 TO R-1 PD R/W-x Z R/W-x DC R/W-x C bit0 R W -n -x = Readable bit = Writable bit = Value at POR reset = Unknown at POR reset IRP: Register Bank Select bit (used for indirect addressing) 1 = Bank 2, 3 (100h - 1FFh) 0 = Bank 0, 1 (00h - FFh) The IRP bit is reserved on the PIC16C55X, always maintain this bit clear. bit 6-5: RP1:RP0: Register Bank Select bits (used for direct addressing) 11 = Bank 3 (180h - 1FFh) 10 = Bank 2 (100h - 17Fh) 01 = Bank 1 (80h - FFh) 00 = Bank 0 (00h - 7Fh) Each bank is 128 bytes. The RP1 bit is reserved on the PIC16C55X, always maintain this bit clear. bit 4: TO: Time-out bit 1 = After power-up, CLRWDT instruction, or SLEEP instruction 0 = A WDT time-out occurred bit 3: PD: Power-down bit 1 = After power-up or by the CLRWDT instruction 0 = By execution of the SLEEP instruction bit 2: Z: Zero bit 1 = The result of an arithmetic or logic operation is zero 0 = The result of an arithmetic or logic operation is not zero bit 1: DC: Digit carry/borrow bit (ADDWF, ADDLW,SUBLW,SUBWF instructions)(for borrow the polarity is reversed) 1 = A carry-out from the 4th low order bit of the result occurred 0 = No carry-out from the 4th low order bit of the result bit 0: C: Carry/borrow bit (ADDWF, ADDLW,SUBLW,SUBWF instructions) 1 = A carry-out from the most significant bit of the result occurred 0 = No carry-out from the most significant bit of the result occurred Note: For borrow the polarity is reversed. A subtraction is executed by adding the two's complement of the second operand. For rotate (RRF, RLF) instructions, this bit is loaded with either the high or low order bit of the source register. DS40143C-page 16 Preliminary 1998 Microchip Technology Inc. PIC16C55X 4.2.2.2 OPTION REGISTER The OPTION register is a readable and writable register which contains various control bits to configure the TMR0/WDT prescaler, the external RB0/INT interrupt, TMR0 and the weak pull-ups on PORTB. FIGURE 4-6: R/W-1 RBPU bit7 Note: To achieve a 1:1 prescaler assignment for TMR0, assign the prescaler to the WDT (PSA = 1). OPTION REGISTER (ADDRESS 81H) R/W-1 INTEDG R/W-1 T0CS R/W-1 T0SE R/W-1 PSA R/W-1 PS2 R/W-1 PS1 bit 7: RBPU: PORTB Pull-up Enable bit 1 = PORTB pull-ups are disabled 0 = PORTB pull-ups are enabled by individual port latch values bit 6: INTEDG: Interrupt Edge Select bit 1 = Interrupt on rising edge of RB0/INT pin 0 = Interrupt on falling edge of RB0/INT pin bit 5: T0CS: TMR0 Clock Source Select bit 1 = Transition on RA4/T0CKI pin 0 = Internal instruction cycle clock (CLKOUT) bit 4: T0SE: TMR0 Source Edge Select bit 1 = Increment on high-to-low transition on RA4/T0CKI pin 0 = Increment on low-to-high transition on RA4/T0CKI pin bit 3: PSA: Prescaler Assignment bit 1 = Prescaler is assigned to the WDT 0 = Prescaler is assigned to the Timer0 module R/W-1 PS0 bit0 R = Readable bit W = Writable bit - n = Value at POR reset bit 2-0: PS2:PS0: Prescaler Rate Select bits Bit Value TMR0 Rate WDT Rate 000 001 010 011 100 101 110 111 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 1 : 256 1:1 1:2 1:4 1:8 1 : 16 1 : 32 1 : 64 1 : 128 1998 Microchip Technology Inc. Preliminary DS40143C-page 17 PIC16C55X 4.2.2.3 INTCON REGISTER Note: The INTCON register is a readable and writable register which contains the various enable and flag bits for all interrupt sources. FIGURE 4-7: Interrupt flag bits get set when an interrupt condition occurs regardless of the state of its corresponding enable bit or the global enable bit, GIE (INTCON<7>). INTCON REGISTER (ADDRESS 0BH OR 8BH) R/W-0 GIE bit7 Reserved -- bit 7: GIE: Global Interrupt Enable bit 1 = Enables all un-masked interrupts 0 = Disables all interrupts bit 6: -- = Reserved for future use. Always maintain this bit clear. bit 5: T0IE: TMR0 Overflow Interrupt Enable bit 1 = Enables the TMR0 interrupt 0 = Disables the TMR0 interrupt bit 4: INTE: RB0/INT External Interrupt Enable bit 1 = Enables the RB0/INT external interrupt 0 = Disables the RB0/INT external interrupt bit 3: RBIE: RB Port Change Interrupt Enable bit 1 = Enables the RB port change interrupt 0 = Disables the RB port change interrupt bit 2: T0IF: TMR0 Overflow Interrupt Flag bit 1 = TMR0 register has overflowed (must be cleared in software) 0 = TMR0 register did not overflow bit 1: INTF: RB0/INT External Interrupt Flag bit 1 = The RB0/INT external interrupt occurred (must be cleared in software) 0 = The RB0/INT external interrupt did not occur bit 0: RBIF: RB Port Change Interrupt Flag bit 1 = When at least one of the RB7:RB4 pins changed state (must be cleared in software) 0 = None of the RB7:RB4 pins have changed state DS40143C-page 18 R/W-0 T0IE R/W-0 INTE R/W-0 RBIE R/W-0 T0IF R/W-0 INTF Preliminary R/W-x RBIF bit0 R W -n -x = Readable bit = Writable bit = Value at POR reset = Unknown at POR reset 1998 Microchip Technology Inc. PIC16C55X 4.2.2.4 PCON REGISTER The PCON register contains flag bits to differentiate between a Power-on Reset, an external MCLR reset or WDT reset. See Section 7.3 and Section 7.4 for detailed reset operation. FIGURE 4-8: U-0 -- bit7 PCON REGISTER (ADDRESS 8Eh) U-0 -- U-0 -- U-0 -- U-0 -- U-0 -- R/W-0 POR U-0 -- bit0 R = Readable bit W = Writable bit U = Unimplemented bit, read as `0' - n = Value at POR reset bit 7-2: Unimplemented: Read as '0' bit 1: POR: Power-on Reset Status bit 1 = No Power-on Reset occurred 0 = Power-on Reset occurred bit 0: Unimplemented: Read as '0' 1998 Microchip Technology Inc. Preliminary DS40143C-page 19 PIC16C55X 4.3 PCL and PCLATH 4.3.2 The program counter (PC) is 13-bits wide. The low byte comes from the PCL register, which is a readable and writable register. The high bits (PC<12:8>) are not directly readable or writable and come from PCLATH. On any reset, the PC is cleared. Figure 4-9 shows the two situations for the loading of the PC. The upper example in the figure shows how the PC is loaded on a write to PCL (PCLATH<4:0> PCH). The lower example in Figure 4-9 shows how the PC is loaded during a CALL or GOTO instruction (PCLATH<4:3> PCH). FIGURE 4-9: LOADING OF PC IN DIFFERENT SITUATIONS PCH The PIC16C55X family has an 8 level deep x 13-bit wide hardware stack (Figure 4-1 and Figure 4-2). The stack space is not part of either program or data space and the stack pointer is not readable or writable. The PC is PUSHed onto the stack when a CALL instruction is executed or an interrupt causes a branch. The stack is POPed in the event of a RETURN, RETLW or a RETFIE instruction execution. PCLATH is not affected by a PUSH or POP operation. The stack operates as a circular buffer. This means that after the stack has been PUSHed eight times, the ninth push overwrites the value that was stored from the first push. The tenth push overwrites the second push (and so on). PCL 12 8 7 0 PC 5 8 PCLATH<4:0> Instruction with PCL as Destination Note 1: There are no STATUS bits to indicate stack overflow or stack underflow conditions. Note 2: ALU result PCLATH PCH 12 11 10 STACK PCL 8 0 7 PC There are no instructions mnemonics called PUSH or POP. These are actions that occur from the execution of the CALL, RETURN, RETLW and RETFIE instructions, or vectoring to an interrupt address. GOTO, CALL 2 PCLATH<4:3> 11 Opcode <10:0> PCLATH 4.3.1 COMPUTED GOTO A computed GOTO is accomplished by adding an offset to the program counter (ADDWF PCL). When doing a table read using a computed GOTO method, care should be exercised if the table location crosses a PCL memory boundary (each 256 byte block). Refer to the application note "Implementing a Table Read" (AN556). DS40143C-page 20 Preliminary 1998 Microchip Technology Inc. PIC16C55X 4.4 Indirect Addressing, INDF and FSR Registers A simple program to clear RAM locations 20h-2Fh using indirect addressing is shown in Example 4-1. The INDF register is not a physical register. Addressing the INDF register will cause indirect addressing. EXAMPLE 4-1: Indirect addressing is possible by using the INDF register. Any instruction using the INDF register actually accesses data pointed to by the file select register (FSR). Reading INDF itself indirectly will produce 00h. Writing to the INDF register indirectly results in a no-operation (although status bits may be affected). An effective 9-bit address is obtained by concatenating the 8-bit FSR register and the IRP bit (STATUS<7>), as shown in Figure 4-10. However, IRP is not used in the PIC16C55X. FIGURE 4-10: movlw movwf clrf incf btfss goto NEXT RP0 bank select 0x20 FSR INDF FSR FSR,4 NEXT ;initialize pointer ;to RAM ;clear INDF register ;inc pointer ;all done? ;no clear next ;yes continue CONTINUE: DIRECT/INDIRECT ADDRESSING PIC16C55X Direct Addressing (1)RP1 INDIRECT ADDRESSING 6 from opcode Indirect Addressing IRP(1) 0 7 bank select location select 00 01 10 FSR register 0 location select 11 00h 00h not used Data Memory 7Fh 7Fh Bank 0 Bank 1 Bank 2 Bank 3 For memory map detail see Figure 4-3 and Figure 4-4. Note 1: The RP1 and IRP bits are reserved, always maintain these bits clear. 1998 Microchip Technology Inc. Preliminary DS40143C-page 21 PIC16C55X NOTES: DS40143C-page 22 Preliminary 1998 Microchip Technology Inc. PIC16C55X 5.0 I/O PORTS FIGURE 5-2: BLOCK DIAGRAM OF RA4 PIN The PIC16C55X have two ports, PORTA and PORTB. 5.1 Data bus PORTA and TRISA Registers PORTA is a 5-bit wide latch. RA4 is a Schmitt Trigger input and an open drain output. Port RA4 is multiplexed with the T0CKI clock input. All other RA port pins have Schmitt Trigger input levels and full CMOS output drivers. All pins have data direction bits (TRIS registers) which can configure these pins as input or output. A '1' in the TRISA register puts the corresponding output driver in a hi- impedance mode. A '0' in the TRISA register puts the contents of the output latch on the selected pin(s). WR PORTA On reset, the TRISA register is set to all inputs. FIGURE 5-1: Data bus WR PortA D BLOCK DIAGRAM OF PORT PINS RA<3:0> CK Q I/O pin(1) Data Latch WR TRISA D Q CK Q VSS Schmitt Trigger input buffer TRISA Latch VSS RD TRISA Q D EN EN RD PORTA TMR0 clock input Q VDD CK Q N Reading the PORTA register reads the status of the pins, whereas writing to it will write to the port latch. All write operations are read-modify-write operations. So a write to a port implies that the port pins are first read, then this value is modified and written to the port data latch. Note: D Q VDD P Data Latch WR TRISA D Q CK Q N VSS Schmitt Trigger input buffer TRIS Latch I/O pin VSS RD TRISA Q D EN RD PORTA 1998 Microchip Technology Inc. Preliminary DS40143C-page 23 PIC16C55X TABLE 5-1: PORTA FUNCTIONS Name Bit # Buffer Type RA0 RA1 RA2 RA3 RA4/T0CKI bit0 bit1 bit2 bit3 bit4 ST ST ST ST ST Legend: SUMMARY OF REGISTERS ASSOCIATED WITH PORTA Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR Value on All Other Resets RA4 RA3 RA2 RA1 RA0 ---x xxxx ---u uuuu ---1 1111 ---1 1111 05h PORTA -- -- -- 85h TRISA -- -- -- Legend: Note: Bi-directional I/O port. Bi-directional I/O port. Bi-directional I/O port. Bi-directional I/O port. Bi-directional I/O port or external clock input for TMR0. Output is open drain type. ST = Schmitt Trigger input TABLE 5-2: Address Function TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 -- = Unimplemented locations, read as `0' x = unknown u = unchanged Shaded bits are not used by PORTA. DS40143C-page 24 Preliminary 1998 Microchip Technology Inc. PIC16C55X 5.2 PORTB and TRISB Registers latched in INTCON<0>). This interrupt can wake the device from SLEEP. The user, in the interrupt service routine, can clear the interrupt in the following manner: PORTB is an 8-bit wide bi-directional port. The corresponding data direction register is TRISB. A '1' in the TRISB register puts the corresponding output driver in a high impedance mode. A '0' in the TRISB register puts the contents of the output latch on the selected pin(s). a) b) A mismatch condition will continue to set flag bit RBIF. Reading PORTB will end the mismatch condition, and allow flag bit RBIF to be cleared. Reading PORTB register reads the status of the pins, whereas writing to it will write to the port latch. All write operations are read-modify-write operations. So a write to a port implies that the port pins are first read, then this value is modified and written to the port data latch. This interrupt on mismatch feature, together with software configurable pull-ups on these four pins allow easy interface to a key pad and make it possible for wake-up on key-depression. (See AN552 in the Microchip Embedded Control Handbook.) Each of the PORTB pins has a weak internal pull-up (200 A typical). A single control bit can turn on all the pull-ups. This is done by clearing the RBPU (OPTION<7>) bit. The weak pull-up is automatically turned off when the port pin is configured as an output. The pull-ups are disabled on Power-on Reset. Note: If a change on the I/O pin should occur when the read operation is being executed (start of the Q2 cycle), then the RBIF interrupt flag may not get set. The interrupt on change feature is recommended for wake-up on key depression operation and operations where PORTB is only used for the interrupt on change feature. Polling of PORTB is not recommended while using the interrupt on change feature. Four of PORTB's pins, RB7:RB4, have an interrupt on change feature. Only pins configured as inputs can cause this interrupt to occur (i.e., any RB7:RB4 pin configured as an output is excluded from the interrupt on change comparison). The input pins (of RB7:RB4) are compared with the old value latched on the last read of PORTB. The "mismatch" outputs of RB7:RB4 are OR'ed together to generate the RBIF interrupt (flag FIGURE 5-3: Any read or write of PORTB. This will end the mismatch condition. Clear flag bit RBIF. BLOCK DIAGRAM OF RB7:RB4 PINS RBPU(1) VDD VDD Data Latch Data bus D WR PortB Q weak P pull-up VDD P CK WR TRISB D Q CK Q RD TRISB I/O pin N TRIS Latch VSS VSS TTL ST Input Buffer Buffer Latch Q D EN RD PortB Set RBIF From other RB7:RB4 pins Q D EN RB7:RB6 in serial programming mode RD Port B Note 1: TRISB = 1 enables weak pull-up if RBPU = '0' (OPTION<7>). 1998 Microchip Technology Inc. Preliminary DS40143C-page 25 PIC16C55X FIGURE 5-4: BLOCK DIAGRAM OF RB3:RB0 PINS RBPU(1) VDD Data Latch Data bus D WR PortB Q VDD P CK D Q CK Q I/O pin N TRIS Latch WR TRISB weak P pull-up VDD VSS VSS TTL ST Input Buffer Buffer RD TRISB Latch D Q RD PortB EN RB0:INT ST Buffer RD Port B Note 1: TRISB = 1 enables weak pull-up if RBPU = '0' (OPTION<7>). TABLE 5-3: Name PORTB FUNCTIONS Bit # Buffer Type Function Input/output or external interrupt input. Internal software programmable weak pull-up. RB1 bit1 TTL Input/output pin. Internal software programmable weak pull-up. RB2 bit2 TTL Input/output pin. Internal software programmable weak pull-up. RB3 bit3 TTL Input/output pin. Internal software programmable weak pull-up. RB4 bit4 TTL Input/output pin (with interrupt on change). Internal software programmable weak pull-up. RB5 bit5 TTL Input/output pin (with interrupt on change). Internal software programmable weak pull-up. (2) RB6 bit6 Input/output pin (with interrupt on change). Internal software TTL/ST programmable weak pull-up. Serial programming clock pin. RB7 bit7 Input/output pin (with interrupt on change). Internal software TTL/ST(2) programmable weak pull-up. Serial programming data pin. Legend: ST = Schmitt Trigger, TTL = TTL input Note 1: This buffer is a Schmitt Trigger input when configured as the external interrupt. Note 2: This buffer is a Schmitt Trigger input when used in serial programming mode. RB0/INT bit0 TABLE 5-4: (1) TTL/ST SUMMARY OF REGISTERS ASSOCIATED WITH PORTB Address Name Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR Value on All Other Rests 06h PORTB RB7 RB6 RB5 RB4 RB3 RB2 RB1 RB0 xxxx xxxx uuuu uuuu 86h TRISB TRISB7 TRISB6 1111 1111 1111 1111 81h OPTION RBPU INTEDG 1111 1111 1111 1111 Legend: Note: TRISB5 TRISB4 TRISB3 TRISB2 TRISB1 TRISB0 T0CS T0SE PSA PS2 PS1 PS0 x = unknown, u = unchanged Shaded bits are not used by PORTB. DS40143C-page 26 Preliminary 1998 Microchip Technology Inc. PIC16C55X 5.3 I/O Programming Considerations 5.3.1 BI-DIRECTIONAL I/O PORTS EXAMPLE 5-1: ; Initial PORT settings: PORTB<7:4> Inputs ; ; PORTB<3:0> Outputs ; PORTB<7:6> have external pull-up and are not ; connected to other circuitry ; ; PORT latch PORT pins ; ---------- ---------- Any instruction which writes, operates internally as a read followed by a write operation. The BCF and BSF instructions, for example, read the register into the CPU, execute the bit operation and write the result back to the register. Caution must be used when these instructions are applied to a port with both inputs and outputs defined. For example, a BSF operation on bit5 of PORTB will cause all eight bits of PORTB to be read into the CPU. Then the BSF operation takes place on bit5 and PORTB is written to the output latches. If another bit of PORTB is used as a bidirectional I/O pin (e.g., bit0) and it is defined as an input at this time, the input signal present on the pin itself would be read into the CPU and re-written to the data latch of this particular pin, overwriting the previous content. As long as the pin stays in the input mode, no problem occurs. However, if bit0 is switched into output mode later on, the content of the data latch may now be unknown. BCF BCF BSF BCF BCF 5.3.2 ; 01pp ; 10pp ; ; 10pp ; 10pp pppp pppp 11pp pppp 11pp pppp pppp pppp 11pp pppp 10pp pppp SUCCESSIVE OPERATIONS ON I/O PORTS The actual write to an I/O port happens at the end of an instruction cycle, whereas for reading, the data must be valid at the beginning of the instruction cycle (Figure 5-5). Therefore, care must be exercised if a write followed by a read operation is carried out on the same I/O port. The sequence of instructions should be such to allow the pin voltage to stabilize (load dependent) before the next instruction which causes that file to be read into the CPU is executed. Otherwise, the previous state of that pin may be read into the CPU rather than the new state. When in doubt, it is better to separate these instructions with an NOP or another instruction not accessing this I/O port. Example 5-1 shows the effect of two sequential read-modify-write instructions (ex., BCF, BSF, etc.) on an I/O port. A pin actively outputting a Low or High should not be driven from external devices at the same time in order to change the level on this pin ("wired-or", "wired-and"). The resulting high output currents may damage the chip. PC Instruction fetched PORTB, 7 PORTB, 6 STATUS,RP0 TRISB, 7 TRISB, 6 ; ; Note that the user may have expected the pin ; values to be 00pp pppp. The 2nd BCF caused ; RB7 to be latched as the pin value (High). Reading the port register, reads the values of the port pins. Writing to the port register writes the value to the port latch. When using read modify write instructions (ex. BCF, BSF, etc.) on a port, the value of the port pins is read, the desired operation is done to this value, and this value is then written to the port latch. FIGURE 5-5: READ-MODIFY-WRITE INSTRUCTIONS ON AN I/O PORT SUCCESSIVE I/O OPERATION Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 PC PC + 1 PC + 2 PC + 3 MOVWF PORTB Write to PORTB MOVF PORTB, W Read PORTB NOP NOP This example shows write to PORTB followed by a read from PORTB. Note that: data setup time = (0.25 TCY - TPD) where TCY = instruction cycle and TPD = propagation delay of Q1 cycle to output valid. RB7:RB0 RB <7:0> TPD Execute MOVWF PORTB 1998 Microchip Technology Inc. Note: Port pin sampled here Execute MOVF PORTB, W Preliminary Therefore, at higher clock frequencies, a write followed by a read may be problematic. Execute NOP DS40143C-page 27 PIC16C55X NOTES: DS40143C-page 28 Preliminary 1998 Microchip Technology Inc. PIC16C55X 6.0 TIMER0 MODULE bit (OPTION<4>). Clearing the T0SE bit selects the rising edge. Restrictions on the external clock input are discussed in detail in Section 6.2. The Timer0 module timer/counter has the following features: * * * * * * The prescaler is shared between the Timer0 module and the WatchdogTimer. The prescaler assignment is controlled in software by the control bit PSA (OPTION<3>). Clearing the PSA bit will assign the prescaler to Timer0. The prescaler is not readable or writable. When the prescaler is assigned to the Timer0 module, prescale value of 1:2, 1:4, ..., 1:256 are selectable. Section 6.3 details the operation of the prescaler. 8-bit timer/counter Readable and writable 8-bit software programmable prescaler Internal or external clock select Interrupt on overflow from FFh to 00h Edge select for external clock Figure 6-1 is a simplified block diagram of the Timer0 module. 6.1 Timer mode is selected by clearing the T0CS bit (OPTION<5>). In timer mode, the TMR0 will increment every instruction cycle (without prescaler). If Timer0 is written, the increment is inhibited for the following two cycles (Figure 6-2 and Figure 6-3). The user can work around this by writing an adjusted value to TMR0. Timer0 interrupt is generated when the TMR0 register timer/counter overflows from FFh to 00h. This overflow sets the T0IF bit. The interrupt can be masked by clearing the T0IE bit (INTCON<5>). The T0IF bit (INTCON<2>) must be cleared in software by the Timer0 module interrupt service routine before re-enabling this interrupt. The Timer0 interrupt cannot wake the processor from SLEEP since the timer is shut off during SLEEP. See Figure 6-4 for Timer0 interrupt timing. Counter mode is selected by setting the T0CS bit. In this mode Timer0 will increment either on every rising or falling edge of pin RA4/T0CKI. The incrementing edge is determined by the source edge (T0SE) control FIGURE 6-1: TIMER0 Interrupt TIMER0 BLOCK DIAGRAM Data bus RA4/T0CKI pin FOSC/4 0 PSout 1 1 Programmable Prescaler 8 Sync with Internal clocks 0 TMR0 PSout (2 Tcy delay) T0SE Set Flag bit T0IF on Overflow PSA PS2:PS0 T0CS Note 1: 2: Bits, T0SE, T0CS, PS2, PS1, PS0 and PSA are located in the OPTION register. The prescaler is shared with Watchdog Timer (Figure 6-6) FIGURE 6-2: PC (Program Counter) TIMER0 (TMR0) TIMING: INTERNAL CLOCK/NO PRESCALER Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 PC-1 Instruction Fetch TMR0 T0 PC PC+1 MOVWF TMR0 MOVF TMR0,W T0+1 Instruction Executed 1998 Microchip Technology Inc. PC+2 MOVF TMR0,W PC+3 MOVF TMR0,W T0+2 NT0 NT0 Write TMR0 executed Read TMR0 reads NT0 Read TMR0 reads NT0 Preliminary PC+4 MOVF TMR0,W NT0 Read TMR0 reads NT0 PC+5 PC+6 MOVF TMR0,W NT0+1 NT0+2 Read TMR0 reads NT0 + 1 T0 Read TMR0 reads NT0 + 2 DS40143C-page 29 PIC16C55X FIGURE 6-3: TIMER0 TIMING: INTERNAL CLOCK/PRESCALE 1:2 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 PC (Program Counter) PC-1 Instruction Fetch PC PC+1 MOVWF TMR0 MOVF TMR0,W Instruction Execute PC+4 PC+5 MOVF TMR0,W PC+6 MOVF TMR0,W NT0+1 NT0 Read TMR0 reads NT0 Write TMR0 executed FIGURE 6-4: PC+3 MOVF TMR0,W T0+1 T0 TMR0 PC+2 MOVF TMR0,W Read TMR0 reads NT0 Read TMR0 reads NT0 Read TMR0 reads NT0 Read TMR0 reads NT0 + 1 TIMER0 INTERRUPT TIMING Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 CLKOUT(3) TMR0 timer FEh FFh 1 T0IF bit (INTCON<2>) 00h 01h 02h 1 GIE bit (INTCON<7>) Interrupt Latency Time INSTRUCTION FLOW PC PC Instruction fetched Inst (PC) Instruction executed Inst (PC-1) PC +1 PC +1 Inst (PC+1) Inst (PC) Dummy cycle 0004h 0005h Inst (0004h) Inst (0005h) Dummy cycle Inst (0004h) Note 1: T0IF interrupt flag is sampled here (every Q1). 2: Interrupt latency = 4Tcy, where Tcy = instruction cycle time. 3: CLKOUT is available only in RC oscillator mode. DS40143C-page 30 Preliminary 1998 Microchip Technology Inc. PIC16C55X 6.2 Using Timer0 with External Clock When a prescaler is used, the external clock input is divided by the asynchronous ripple-counter type prescaler so that the prescaler output is symmetrical. For the external clock to meet the sampling requirement, the ripple-counter must be taken into account. Therefore, it is necessary for T0CKI to have a period of at least 4TOSC (and a small RC delay of 40 ns) divided by the prescaler value. The only requirement on T0CKI high and low time is that they do not violate the minimum pulse width requirement of 10 ns. Refer to parameters 40, 41 and 42 in the electrical specification of the desired device. When an external clock input is used for Timer0, it must meet certain requirements. The external clock requirement is due to internal phase clock (TOSC) synchronization. Also, there is a delay in the actual incrementing of Timer0 after synchronization. 6.2.1 EXTERNAL CLOCK SYNCHRONIZATION When no prescaler is used, the external clock input is the same as the prescaler output. The synchronization of T0CKI with the internal phase clocks is accomplished by sampling the prescaler output on the Q2 and Q4 cycles of the internal phase clocks (Figure 6-5). Therefore, it is necessary for T0CKI to be high for at least 2TOSC (and a small RC delay of 20 ns) and low for at least 2TOSC (and a small RC delay of 20 ns). Refer to the electrical specification of the desired device. FIGURE 6-5: 6.2.2 TIMER0 INCREMENT DELAY Since the prescaler output is synchronized with the internal clocks, there is a small delay from the time the external clock edge occurs to the time the TMR0 is actually incremented. Figure 6-5 shows the delay from the external clock edge to the timer incrementing. TIMER0 TIMING WITH EXTERNAL CLOCK Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 External Clock Input or Prescaler output (2) Q1 Q2 Q3 Q4 Small pulse misses sampling (1) (3) External Clock/Prescaler Output after sampling Increment Timer0 (Q4) Timer0 T0 T0 + 1 T0 + 2 Note 1: Delay from clock input change to Timer0 increment is 3Tosc to 7Tosc. (Duration of Q = Tosc). Therefore, the error in measuring the interval between two edges on Timer0 input = 4Tosc max. 2: External clock if no prescaler selected, Prescaler output otherwise. 3: The arrows indicate the points in time where sampling occurs. 1998 Microchip Technology Inc. Preliminary DS40143C-page 31 PIC16C55X 6.3 Prescaler The PSA and PS2:PS0 bits (OPTION<3:0>) determine the prescaler assignment and prescale ratio. An 8-bit counter is available as a prescaler for the Timer0 module, or as a postscaler for the Watchdog Timer, respectively (Figure 6-6). For simplicity, this counter is being referred to as "prescaler" throughout this data sheet. Note that there is only one prescaler available which is mutually exclusive between the Timer0 module and the Watchdog Timer. Thus, a prescaler assignment for the Timer0 module means that there is no prescaler for the Watchdog Timer, and vice-versa. FIGURE 6-6: When assigned to the Timer0 module, all instructions writing to the TMR0 register (e.g., CLRF 1, MOVWF 1, BSF 1,x....etc.) will clear the prescaler. When assigned to WDT, a CLRWDT instruction will clear the prescaler along with the Watchdog Timer. The prescaler is not readable or writable. BLOCK DIAGRAM OF THE TIMER0/WDT PRESCALER Data Bus CLKOUT (=Fosc/4) 0 T0CKI pin 8 M U X 1 M U X 0 1 SYNC 2 Tcy TMR0 reg T0SE T0CS 0 Watchdog Timer 1 M U X Set flag bit T0IF on Overflow PSA 8-bit Prescaler 8 8-to-1MUX PS0 - PS2 PSA WDT Enable bit 1 0 MUX PSA WDT Time-out Note: T0SE, T0CS, PSA, PS0-PS2 are bits in the OPTION register. DS40143C-page 32 Preliminary 1998 Microchip Technology Inc. PIC16C55X 6.3.1 SWITCHING PRESCALER ASSIGNMENT The prescaler assignment is fully under software control (i.e., it can be changed "on the fly" during program execution). To avoid an unintended device RESET, the following instruction sequence (Example 6-1) must be executed when changing the prescaler assignment from Timer0 to WDT. Lines 5-7 are required only if the desired postscaler rate is 1:1 (PS<2:0> = 000) or 1:2 (PS<2:0> = 001). EXAMPLE 6-1: To change prescaler from the WDT to the TMR0 module use the sequence shown in Example 6-2. This precaution must be taken even if the WDT is disabled. EXAMPLE 6-2: CLRWDT CHANGING PRESCALER (TIMER0WDT) 1.BCF STATUS, RP0 ;Skip if already in ; Bank 0 2.CLRWDT ;Clear WDT 3.CLRF TMR0 ;Clear TMR0 & Prescaler 4.BSF STATUS, RP0 ;Bank 1 5.MOVLW '00101111'b; ;These 3 lines (5, 6, 7) 6.MOVWF OPTION ; are required only if ; desired PS<2:0> are 7.CLRWDT ; 000 or 001 8.MOVLW '00101xxx'b ;Set Postscaler to 9.MOVWF OPTION ; desired WDT rate 10.BCF STATUS, RP0 ;Return to Bank 0 TABLE 6-1: Address Name 01h TMR0 0Bh/8Bh INTCON 81h OPTION 85h TRISA CHANGING PRESCALER (WDTTIMER0) ;Clear WDT and ;prescaler BSF MOVLW STATUS, RP0 b'xxxx0xxx' MOVWF BCF OPTION STATUS, RP0 ;Select TMR0, new ;prescale value and ;clock source REGISTERS ASSOCIATED WITH TIMER0 Bit 7 Bit 6 Bit 5 Bit 4 Bit 3 Bit 2 Bit 1 Bit 0 Value on POR xxxx xxxx uuuu uuuu INTE RBIE T0IF INTF RBIF 0000 000x 0000 000x T0SE PSA PS2 PS1 PS0 Timer0 module's register GIE + T0IE RBPU INTEDG T0CS -- -- -- TRISA4 TRISA3 TRISA2 TRISA1 TRISA0 Value on All Other Resets 1111 1111 1111 1111 ---1 1111 ---1 1111 Legend: -- = Unimplemented locations, read as `0'. + = Reserved for future use. Note: Shaded bits are not used by TMR0 module. 1998 Microchip Technology Inc. Preliminary DS40143C-page 33 PIC16C55X NOTES: DS40143C-page 34 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.0 SPECIAL FEATURES OF THE CPU What sets a microcontroller apart from other processors are special circuits to deal with the needs of real time applications. The PIC16C55X family has a host of such features intended to maximize system reliability, minimize cost through elimination of external components, provide power saving operating modes and offer code protection. These are: 1. 2. 3. 4. 5. 6. 7. 8. OSC selection Reset Power-on Reset (POR) Power-up Timer (PWRT) Oscillator Start-Up Timer (OST) Interrupts Watchdog Timer (WDT) SLEEP Code protection ID Locations In-circuit serial programmingTM 1998 Microchip Technology Inc. The PIC16C55X has a Watchdog Timer which is controlled by configuration bits. It runs off its own RC oscillator for added reliability. There are two timers that offer necessary delays on power-up. One is the Oscillator Start-up Timer (OST), intended to keep the chip in reset until the crystal oscillator is stable. The other is the Power-up Timer (PWRT), which provides a fixed delay of 72 ms (nominal) on power-up only, designed to keep the part in reset while the power supply stabilizes. With these two functions on-chip, most applications need no external reset circuitry. The SLEEP mode is designed to offer a very low current power-down mode. The user can wake-up from SLEEP through external reset, Watchdog Timer wake-up or through an interrupt. Several oscillator options are also made available to allow the part to fit the application. The RC oscillator option saves system cost while the LP crystal option saves power. A set of configuration bits are used to select various options. Preliminary DS40143C-page 35 PIC16C55X 7.1 Configuration Bits The configuration bits can be programmed (read as '0') or left unprogrammed (read as '1') to select various device configurations. These bits are mapped in program memory location 2007h. FIGURE 7-1: CP1 CP01 The user will note that address 2007h is beyond the user program memory space. In fact, it belongs to the special test/configuration memory space (2000h - 3FFFh), which can be accessed only during programming. CONFIGURATION WORD CP1 CP01 CP1 CP01 -- Reserved CP1 CP01 PWRTE WDTE F0SC1 F0SC0 bit13 bit0 bit 13-8 5-4: CP<1:0>: Code protection bits(1) bit 7: Unimplemented: Read as '1' bit 6: Reserved: Do not use bit 3: PWRTE: Power-up Timer Enable bit 1 = PWRT disabled 0 = PWRT enabled bit 2: WDTE: Watchdog Timer Enable bit 1 = WDT enabled 0 = WDT disabled bit 1-0: FOSC1:FOSC0: Oscillator Selection bits 11 = RC oscillator 10 = HS oscillator 01 = XT oscillator 00 = LP oscillator CONFIG Address REGISTER: 2007h 11 = Program Memory code protection off 10 = 0400h - 07FFh code protected 01 = 0200h - 07FFh code protected 11 = 0000h - 07FFh code protected Note 1: All of the CP1:CP0 pairs have to be given the same value to enable the code protection scheme listed. DS40143C-page 36 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.2 Oscillator Configurations 7.2.1 OSCILLATOR TYPES TABLE 7-1: The PIC16C55X can be operated in four different oscillator options. The user can program two configuration bits (FOSC1 and FOSC0) to select one of these four modes: * * * * LP XT HS RC 7.2.2 Low Power Crystal Crystal/Resonator High Speed Crystal/Resonator Resistor/Capacitor CRYSTAL OSCILLATOR / CERAMIC RESONATORS In XT, LP or HS modes a crystal or ceramic resonator is connected to the OSC1 and OSC2 pins to establish oscillation (Figure 7-2). The PIC16C55X oscillator design requires the use of a parallel cut crystal. Use of a series cut crystal may give a frequency out of the crystal manufacturers specifications. When in XT, LP or HS modes, the device can have an external clock source to drive the OSC1 pin (Figure 7-3). FIGURE 7-2: Ranges Characterized: Mode Freq OSC1(C1) OSC2(C2) XT 455 kHz 2.0 MHz 4.0 MHz 22 - 100 pF 15 - 68 pF 15 - 68 pF 22 - 100 pF 15 - 68 pF 15 - 68 pF HS 8.0 MHz 16.0 MHz 10 - 68 pF 10 - 22 pF 10 - 68 pF 10 - 22 pF Higher capacitance increases the stability of the oscillator but also increases the start-up time. These values are for design guidance only. Since each resonator has its own characteristics, the user should consult with the resonator manufacturer for appropriate values of external components. TABLE 7-2: Freq OSC1(C1) OSC2(C2) LP 32 kHz 200 kHz 68 - 100 pF 15 - 30 pF 68 - 100 pF 15 - 30 pF XT 100 kHz 2 MHz 4 MHz 68 - 150 pF 15 - 30 pF 15 - 30 pF 150 - 200 pF 15 - 30 pF 15 - 30 pF HS 8 MHz 10 MHz 20 MHz 15 - 30 pF 15 - 30 pF 15 - 30 pF 15 - 30 pF 15 - 30 pF 15 - 30 pF OSC1 To internal logic XTAL RF SLEEP Higher capacitance increases the stability of the oscillator but also increases the start-up time. These values are for design guidance only. Rs may be required in HS mode as well as XT mode to avoid overdriving crystals with low drive level specification. Since each crystal has its own characteristics, the user should consult with the crystal manufacturer for appropriate values of external components. OSC2 RS C2 see Note PIC16C55X See Table 7-1 and Table 7-2 for recommended values of C1 and C2. Note: CAPACITOR SELECTION FOR CRYSTAL OSCILLATOR (PRELIMINARY) Mode CRYSTAL OPERATION (OR CERAMIC RESONATOR) (HS, XT OR LP OSC CONFIGURATION) C1 CAPACITOR SELECTION FOR CERAMIC RESONATORS (PRELIMINARY) A series resistor may be required for AT strip cut crystals. FIGURE 7-3: EXTERNAL CLOCK INPUT OPERATION (HS, XT OR LP OSC CONFIGURATION) Clock from ext. system OSC1 Open OSC2 PIC16C55X 1998 Microchip Technology Inc. Preliminary DS40143C-page 37 PIC16C55X 7.2.3 EXTERNAL CRYSTAL OSCILLATOR CIRCUIT 7.2.4 Either a pre-packaged oscillator can be used or a simple oscillator circuit with TTL gates can be built. Prepackaged oscillators provide a wide operating range and better stability. A well-designed crystal oscillator will provide good performance with TTL gates. Two types of crystal oscillator circuits can be used; one with series resonance, or one with parallel resonance. Figure 7-4 shows implementation of a parallel resonant oscillator circuit. The circuit is designed to use the fundamental frequency of the crystal. The 74AS04 inverter performs the 180 phase shift that a parallel oscillator requires. The 4.7 k resistor provides the negative feedback for stability. The 10 k potentiometers bias the 74AS04 in the linear region. This could be used for external oscillator designs. FIGURE 7-4: EXTERNAL PARALLEL RESONANT CRYSTAL OSCILLATOR CIRCUIT +5V To other Devices 10k PIC16C55X 74AS04 4.7k For timing insensitive applications the "RC" device option offers additional cost savings. The RC oscillator frequency is a function of the supply voltage, the resistor (Rext) and capacitor (Cext) values, and the operating temperature. In addition to this, the oscillator frequency will vary from unit to unit due to normal process parameter variation. Furthermore, the difference in lead frame capacitance between package types will also affect the oscillation frequency, especially for low Cext values. The user also needs to take into account variation due to tolerance of external R and C components used. Figure 7-6 shows how the R/C combination is connected to the PIC16C55X. For Rext values below 2.2 k, the oscillator operation may become unstable, or stop completely. For very high Rext values (e.g., 1 M), the oscillator becomes sensitive to noise, humidity and leakage. Thus, we recommend to keep Rext between 3 k and 100 k. Although the oscillator will operate with no external capacitor (Cext = 0 pF), we recommend using values above 20 pF for noise and stability reasons. With no or small external capacitance, the oscillation frequency can vary dramatically due to changes in external capacitances, such as PCB trace capacitance or package lead frame capacitance. The oscillator frequency, divided by 4, is available on the OSC2/CLKOUT pin, and can be used for test purposes or to synchronize other logic (Figure 3-2 for waveform). CLKIN 74AS04 RC OSCILLATOR 10k XTAL FIGURE 7-6: RC OSCILLATOR MODE 10k VDD 20 pF 20 pF PIC16C55X Rext Figure 7-5 shows a series resonant oscillator circuit. This circuit is also designed to use the fundamental frequency of the crystal. The inverter performs a 180 phase shift in a series resonant oscillator circuit. The 330 resistors provide the negative feedback to bias the inverters in their linear region. FIGURE 7-5: OSC1 Internal Clock Cext VDD Fosc/4 OSC2/CLKOUT EXTERNAL SERIES RESONANT CRYSTAL OSCILLATOR CIRCUIT 330 330 74AS04 74AS04 To other Devices PIC16C55X 74AS04 CLKIN 0.1 F XTAL DS40143C-page 38 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.3 Reset The PIC16C55X differentiates between various kinds of reset: a) b) c) d) e) Power-on reset (POR) MCLR reset during normal operation MCLR reset during SLEEP WDT reset (normal operation) WDT wake-up (SLEEP) A simplified block diagram of the on-chip reset circuit is shown in Figure 7-7. Some registers are not affected in any reset condition; their status is unknown on POR and unchanged in any other reset. Most other registers are reset to a "reset state" on Power-on reset, on MCLR or WDT reset and FIGURE 7-7: on MCLR reset during SLEEP. They are not affected by a WDT wake-up, since this is viewed as the resumption of normal operation. TO and PD bits are set or cleared differently in different reset situations as indicated in Table 7-4. These bits are used in software to determine the nature of the reset. See Table 7-6 for a full description of reset states of all registers. The MCLR reset path has a noise filter to detect and ignore small pulses. See Table 10-4 for pulse width specification. SIMPLIFIED BLOCK DIAGRAM OF ON-CHIP RESET CIRCUIT External Reset MCLR/ VPP Pin WDT Module SLEEP WDT Time-out Reset VDD rise detect Power-on Reset VDD S OST/PWRT OST Chip_Reset 10-bit Ripple-counter OSC1/ CLKIN Pin On-chip(1) RC OSC R Q PWRT 10-bit Ripple-counter Enable PWRT See Table 7-3 for time-out situations. Enable OST Note 1: This is a separate oscillator from the RC oscillator of the CLKIN pin. 1998 Microchip Technology Inc. Preliminary DS40143C-page 39 PIC16C55X 7.4 7.4.1 Power-on Reset (POR), Power-up Timer (PWRT), Oscillator Start-up Timer (OST) 7.4.3 The Oscillator Start-Up Timer (OST) provides a 1024 oscillator cycle (from OSC1 input) delay after the PWRT delay is over. This ensures that the crystal oscillator or resonator has started and stabilized. POWER-ON RESET (POR) A Power-on Reset pulse is generated on-chip when VDD rise is detected (in the range of 1.6 V - 1.8 V). To take advantage of the POR, just tie the MCLR pin through a resistor to VDD. This will eliminate external RC components usually needed to create Power-on Reset. A maximum rise time for VDD is required. See Electrical Specifications for details. The POR circuit does not produce internal reset when VDD declines. When the device starts normal operation (exits the reset condition), device operating parameters (voltage, frequency, temperature, etc.) must be met to ensure operation. If these conditions are not met, the device must be held in reset until the operating conditions are met. For additional information, refer to Application Note AN607 "Power-up Trouble Shooting". 7.4.2 POWER-UP TIMER (PWRT) The Power-up Timer provides a fixed 72 ms (nominal) time-out on power-up only, from POR. The Power-up Timer operates on an internal RC oscillator. The chip is kept in reset as long as PWRT is active. The PWRT delay allows the VDD to rise to an acceptable level. A configuration bit, PWRTE can disable (if set) or enable (if cleared or programmed) the Power-up Timer. The Power-Up Time delay will vary from chip to chip and due to VDD, temperature and process variation. See DC parameters for details. DS40143C-page 40 OSCILLATOR START-UP TIMER (OST) The OST time-out is invoked only for XT, LP and HS modes and only on power-on reset or wake-up from SLEEP. 7.4.4 TIME-OUT SEQUENCE On power-up, the time-out sequence is as follows: First PWRT time-out is invoked after POR has expired, then OST is activated. The total time-out will vary based on oscillator configuration and PWRTE bit status. For example, in RC mode with PWRTE bit erased (PWRT disabled), there will be no time-out at all. Figure 7-8, Figure 7-9 and Figure 7-10 depict time-out sequences. Since the time-outs occur from the POR pulse, if MCLR is kept low long enough, the time-outs will expire. Then bringing MCLR high will begin execution immediately (see Figure 7-9). This is useful for testing purposes or to synchronize more than one PIC16C55X device operating in parallel. Table 7-5 shows the reset conditions for some special registers, while Table 7-6 shows the reset conditions for all the registers. Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.4.5 POWER CONTROL/STATUS REGISTER (PCON) Bit1 is POR (Power-on-reset). It is a `0' on power-on-reset and unaffected otherwise. The user must write a `1' to this bit following a power-on-reset. On a subsequent reset if POR is `0', it will indicate that a power-on-reset must have occurred (VDD may have gone too low). TABLE 7-3: TIME-OUT IN VARIOUS SITUATIONS Power-up Oscillator Configuration TABLE 7-4: Wake-up from SLEEP PWRTE = 0 PWRTE = 1 XT, HS, LP 72 ms + 1024 TOSC 1024 TOSC 1024 TOSC RC 72 ms -- -- STATUS BITS AND THEIR SIGNIFICANCE POR TO PD 0 1 1 Power-on-reset 0 0 X Illegal, TO is set on POR 0 X 0 Illegal, PD is set on POR 1 0 u WDT Reset 1 0 0 WDT Wake-up 1 u u MCLR reset during normal operation 1 1 0 MCLR reset during SLEEP 1998 Microchip Technology Inc. Preliminary DS40143C-page 41 PIC16C55X TABLE 7-5: INITIALIZATION CONDITION FOR SPECIAL REGISTERS Program Counter STATUS Register PCON Register Power-on Reset 000h 0001 1xxx ---- --0- MCLR reset during normal operation 000h 000u uuuu ---- --u- MCLR reset during SLEEP 000h 0001 0uuu ---- --u- WDT reset 000h 0000 uuuu ---- --u- PC + 1 uuu0 0uuu ---- --u- uuu1 0uuu ---- --u- Condition WDT Wake-up Interrupt Wake-up from SLEEP PC + 1(1) Legend: u = unchanged, x = unknown, - = unimplemented bit, reads as `0'. Note 1: When the wake-up is due to an interrupt and global enable bit, GIE is set, the PC is loaded with the interrupt vector (0004h) after execution of PC+1. TABLE 7-6: INITIALIZATION CONDITION FOR REGISTERS Register Address W - INDF 00h TMR0 01h PCL Power-on Reset * MCLR Reset during normal operation * MCLR Reset during SLEEP * WDT Reset 02h xxxx xxxx xxxx xxxx 0000 0000 uuuu uuuu uuuu uuuu 0000 0000 STATUS 03h 0001 1xxx FSR 04h PORTA 05h PORTB 06h PCLATH 0Ah INTCON 0Bh xxxx ---x xxxx ---0 0000 xxxx xxxx xxxx 0000 000x 000q uuuu ---u uuuu ---0 0000 OPTION 81h TRISA 85h TRISB 86h PCON 8Eh 1111 ---1 1111 ---- 1111 1111 1111 --0- quuu(3) uuuu uuuu uuuu 0000 000u 1111 1111 ---1 1111 1111 1111 * Wake up from SLEEP through interrupt * Wake up from SLEEP through WDT time-out uuuu uuuu uuuu uuuu PC + 1(2) uuuq uuuu ---u uuuu ---u quuu(3) uuuu uuuu uuuu uuuu uuuu uuuu ---u uuuu ---- uuuu(1) uuuu uuuu uuuu --u- ---- --uLegend: u = unchanged, x = unknown, - = unimplemented bit, reads as `0',q = value depends on condition. Note 1: One or more bits in INTCON will be affected (to cause wake-up). 2: When the wake-up is due to an interrupt and the GIE bit is set, the PC is loaded with the interrupt vector (0004h). 3: See Table 7-5 for reset value for specific condition. DS40143C-page 42 Preliminary 1998 Microchip Technology Inc. PIC16C55X FIGURE 7-8: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 1 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 7-9: TIME-OUT SEQUENCE ON POWER-UP (MCLR NOT TIED TO VDD): CASE 2 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET FIGURE 7-10: TIME-OUT SEQUENCE ON POWER-UP (MCLR TIED TO VDD): CASE 3 VDD MCLR INTERNAL POR TPWRT PWRT TIME-OUT TOST OST TIME-OUT INTERNAL RESET 1998 Microchip Technology Inc. Preliminary DS40143C-page 43 PIC16C55X FIGURE 7-11: EXTERNAL POWER-ON RESET CIRCUIT (FOR SLOW VDD POWER-UP) VDD VDD D R R1 MCLR C PIC16C55X Note 1: External power-on reset circuit is required only if VDD power-up slope is too slow. The diode D helps discharge the capacitor quickly when VDD powers down. 2: < 40 k is recommended to make sure that voltage drop across R does not violate the device's electrical specification. 3: R1 = 100 to 1 k will limit any current flowing into MCLR from external capacitor C in the event of MCLR/VPP pin breakdown due to Electrostatic Discharge (ESD) or Electrical Overstress (EOS). DS40143C-page 44 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.5 Interrupts The PIC16C55X has 3 sources of interrupt: * External interrupt RB0/INT * TMR0 overflow interrupt * PortB change interrupts (pins RB7:RB4) The interrupt control register (INTCON) records individual interrupt requests in flag bits. It also has individual and global interrupt enable bits. A global interrupt enable bit, GIE (INTCON<7>) enables (if set) all un-masked interrupts or disables (if cleared) all interrupts. Individual interrupts can be disabled through their corresponding enable bits in INTCON register. GIE is cleared on reset. For external interrupt events, such as the INT pin or PORTB change interrupt, the interrupt latency will be three or four instruction cycles. The exact latency depends when the interrupt event occurs (Figure 7-13). The latency is the same for one or two cycle instructions. Once in the interrupt service routine the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bit(s) must be cleared in software before re-enabling interrupts to avoid multiple interrupt requests. Individual interrupt flag bits are set regardless of the status of their corresponding mask bit or the GIE bit. Note 1: Individual interrupt flag bits are set regardless of the status of their corresponding mask bit or the GIE bit. 2: When an instruction that clears the GIE bit is executed, any interrupts that were pending for execution in the next cycle are ignored. The CPU will execute a NOP in the cycle immediately following the instruction which clears the GIE bit. The interrupts which were ignored are still pending to be serviced when the GIE bit is set again. The "return from interrupt" instruction, RETFIE, exits the interrupt routine as well as sets the GIE bit, which re-enables RB0/INT interrupts. The INT pin interrupt, the RB port change interrupt and the TMR0 overflow interrupt flags are contained in the INTCON register. When an interrupt is responded to, the GIE is cleared to disable any further interrupt, the return address is pushed into the stack and the PC is loaded with 0004h. Once in the interrupt service routine the source(s) of the interrupt can be determined by polling the interrupt flag bits. The interrupt flag bit(s) must be cleared in software before re-enabling interrupts to avoid RB0/INT recursive interrupts. FIGURE 7-12: INTERRUPT LOGIC Wake-up (If in SLEEP mode) T0IF T0IE INTF INTE Interrupt to CPU RBIF RBIE GIE 1998 Microchip Technology Inc. Preliminary DS40143C-page 45 PIC16C55X 7.5.1 7.5.2 RB0/INT INTERRUPT TMR0 INTERRUPT An overflow (FFh 00h) in the TMR0 register will set the T0IF (INTCON<2>) bit. The interrupt can be enabled/disabled by setting/clearing T0IE (INTCON<5>) bit. For operation of the Timer0 module, see Section 6.0. An external interrupt on RB0/INT pin is edge triggered: either rising if INTEDG bit (OPTION<6>) is set, or falling if INTEDG bit is clear. When a valid edge appears on the RB0/INT pin, the INTF bit (INTCON<1>) is set. This interrupt can be disabled by clearing the INTE control bit (INTCON<4>). The INTF bit must be cleared in software in the interrupt service routine before re-enabling this interrupt. The RB0/INT interrupt can wake-up the processor from SLEEP, if the INTE bit was set prior to going into SLEEP. The status of the GIE bit decides whether or not the processor branches to the interrupt vector following wake-up. See Section 7.8 for details on SLEEP and Figure 7-16 for timing of wake-up from SLEEP through RB0/INT interrupt. 7.5.3 PORTB INTERRUPT An input change on PORTB <7:4> sets the RBIF (INTCON<0>) bit. The interrupt can be enabled/disabled by setting/clearing the RBIE (INTCON<4>) bit. For operation of PORTB (Section 5.2). Note: If a change on the I/O pin should occur when the read operation is being executed (start of the Q2 cycle), then the RBIF interrupt flag may get set. FIGURE 7-13: INT PIN INTERRUPT TIMING Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 CLKOUT 3 4 INT pin 1 1 INTF flag (INTCON<1>) Interrupt Latency 2 5 GIE bit (INTCON<7>) INSTRUCTION FLOW PC PC+1 PC+1 Instruction fetched Inst (PC) Inst (PC+1) -- Instruction executed Inst (PC-1) PC Inst (PC) Dummy Cycle 0004h 0005h Inst (0004h) Inst (0005h) Dummy Cycle Inst (0004h) Note 1: INTF flag is sampled here (every Q1). 2: Interrupt latency = 3-4 Tcy where Tcy = instruction cycle time. Latency is the same whether Inst (PC) is a single cycle or a 2-cycle instruction. 3: CLKOUT is available only in RC oscillator mode. 4: For minimum width of INT pulse, refer to AC specs. 5: INTF is enabled to be set anytime during the Q4-Q1 cycles. DS40143C-page 46 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.6 Context Saving During Interrupts 7.7 During an interrupt, only the return PC value is saved on the stack. Typically, users may wish to save key registers during an interrupt, e.g. W register and STATUS register. This will have to be implemented in software. Example 7-1 stores and restores the STATUS and W registers. The user register, W_TEMP, must be defined in both banks and must be defined at the same offset from the bank base address (i.e., W_TEMP is defined at 0x20 in Bank 0 and it must also be defined at 0xA0 in Bank 1). The user register, STATUS_TEMP, must be defined in Bank 0. The Example 7-1: * * * * Stores the W register Stores the STATUS register in Bank 0 Executes the ISR code Restores the STATUS (and bank select bit register) * Restores the W register EXAMPLE 7-1: MOVWF W_TEMP ;copy W to temp register, ;could be in either bank SWAPF STATUS,W ;swap status to be saved into W BCF STATUS,RP0 ;change to bank 0 regardless ;of current bank MOVWF STATUS_TEMP ;save status to bank 0 ;register The WDT has a nominal time-out period of 18 ms, (with no prescaler). The time-out periods vary with temperature, VDD and process variations from part to part (see DC specs). If longer time-out periods are desired, a prescaler with a division ratio of up to 1:128 can be assigned to the WDT under software control by writing to the OPTION register. Thus, time-out periods up to 2.3 seconds can be realized. The CLRWDT and SLEEP instructions clear the WDT and the postscaler, if assigned to the WDT, and prevent it from timing out and generating a device RESET. 7.7.2 (ISR) : SWAPF STATUS_TEMP,W ;swap STATUS_TEMP register ;into W, sets bank to original ;state MOVWF STATUS ;move W into STATUS register SWAPF W_TEMP,F ;swap W_TEMP SWAPF W_TEMP,W ;swap W_TEMP into W 1998 Microchip Technology Inc. WDT PERIOD The TO bit in the STATUS register will be cleared upon a Watchdog Timer time-out. : : The watchdog timer is a free running on-chip RC oscillator which does not require any external components. This RC oscillator is separate from the RC oscillator of the CLKIN pin. That means that the WDT will run, even if the clock on the OSC1 and OSC2 pins of the device has been stopped, for example, by execution of a SLEEP instruction. During normal operation, a WDT time-out generates a device RESET. If the device is in SLEEP mode, a WDT time-out causes the device to wake-up and continue with normal operation. The WDT can be permanently disabled by programming the configuration bit WDTE as clear (Section 7.1). 7.7.1 SAVING THE STATUS AND W REGISTERS IN RAM Watchdog Timer (WDT) WDT PROGRAMMING CONSIDERATIONS It should also be taken in account that under worst case conditions (VDD = Min., Temperature = Max., max. WDT prescaler) it may take several seconds before a WDT time-out occurs. Preliminary DS40143C-page 47 PIC16C55X FIGURE 7-14: WATCHDOG TIMER BLOCK DIAGRAM From TMR0 Clock Source (Figure 6-6) 0 Watchdog Timer 1 * M U X Postscaler 8 8 - to -1 MUX PS<2:0> * To TMR0 (Figure 6-6) PSA WDT Enable Bit 1 0 MUX PSA WDT Time-out Note: T0SE, T0CS, PSA, PS0-PS2 are bits in the OPTION register. FIGURE 7-15: SUMMARY OF WATCHDOG TIMER REGISTERS Address Name 2007h Config. bits 81h OPTION Bit 7 -- RBPU Bit 6 + Bit 5 Bit 4 CP1 CP0 Bit 3 Bit 2 PWRTE WDTE INTEDG T0CS T0SE PSA PS2 Bit 1 Bit 0 FOSC1 FOSC0 PS1 PS0 Value on POR 1111 1111 Value on all other Resets 1111 1111 Legend: Shaded cells are not used by the Watchdog Timer. -- = Unimplemented location, read as `0'. + = Reserved for future use. DS40143C-page 48 Preliminary 1998 Microchip Technology Inc. PIC16C55X 7.8 Power-Down Mode (SLEEP) The Power-down mode is entered by executing a SLEEP instruction. If enabled, the Watchdog Timer will be cleared but keeps running, the PD bit in the STATUS register is cleared, the TO bit is set, and the oscillator driver is turned off. The I/O ports maintain the status they had, before SLEEP was executed (driving high, low, or hi-impedance). For lowest current consumption in this mode, all I/O pins should be either at VDD, or VSS, with no external circuitry drawing current from the I/O pin. I/O pins that are hi-impedance inputs should be pulled high or low externally to avoid switching currents caused by floating inputs. The T0CKI input should also be at VDD or VSS for lowest current consumption. The contribution from on chip pull-ups on PORTB should be considered. The MCLR pin must be at a logic high level (VIHMC). Note: 7.8.1 It should be noted that a RESET generated by a WDT time-out does not drive MCLR pin low. WAKE-UP FROM SLEEP The device can wake-up from SLEEP through one of the following events: 1. 2. 3. The first event will cause a device reset. The two latter events are considered a continuation of program execution. The TO and PD bits in the STATUS register can be used to determine the cause of device reset. PD bit, which is set on power-up is cleared when SLEEP is invoked. TO bit is cleared if WDT Wake-up occurred. When the SLEEP instruction is being executed, the next instruction (PC + 1) is pre-fetched. For the device to wake-up through an interrupt event, the corresponding interrupt enable bit must be set (enabled). Wake-up is regardless of the state of the GIE bit. If the GIE bit is clear (disabled), the device continues execution at the instruction after the SLEEP instruction. If the GIE bit is set (enabled), the device executes the instruction after the SLEEP instruction and then branches to the interrupt address (0004h). In cases where the execution of the instruction following SLEEP is not desirable, the user should have an NOP after the SLEEP instruction. Note: If the global interrupts are disabled (GIE is cleared), but any interrupt source has both its interrupt enable bit and the corresponding interrupt flag bits set, the device will immediately wakeup from sleep. The sleep instruction is completely executed. The WDT is cleared when the device wakes-up from sleep, regardless of the source of wake-up. External reset input on MCLR pin Watchdog Timer Wake-up (if WDT was enabled) Interrupt from RB0/INT pin or RB Port change FIGURE 7-16: WAKE-UP FROM SLEEP THROUGH INTERRUPT Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 Q1 Q2 Q3 Q4 OSC1 TOST(2) CLKOUT(4) INT pin INTF flag (INTCON<1>) Interrupt Latency (Note 2) GIE bit (INTCON<7>) Processor in SLEEP INSTRUCTION FLOW PC PC Instruction fetched Inst(PC) = SLEEP Instruction executed Inst(PC - 1) Note 1: 2: 3: 4: PC+1 PC+2 PC+2 Inst(PC + 1) Inst(PC + 2) SLEEP Inst(PC + 1) PC + 2 Dummy cycle 0004h 0005h Inst(0004h) Inst(0005h) Dummy cycle Inst(0004h) XT, HS or LP oscillator mode assumed. TOST = 1024TOSC (drawing not to scale) This delay will not be there for RC osc mode. GIE = '1' assumed. In this case after wake- up, the processor jumps to the interrupt routine. If GIE = '0', execution will continue in-line. CLKOUT is not available in these osc modes, but shown here for timing reference. 1998 Microchip Technology Inc. Preliminary DS40143C-page 49 PIC16C55X 7.9 Code Protection 7.11 If the code protection bit(s) have not been programmed, the on-chip program memory can be read out for verification purposes. Note: 7.10 Microchip does not recommend code protecting windowed devices. ID Locations Four memory locations (2000h-2003h) are designated as ID locations where the user can store checksum or other code-identification numbers. These locations are not accessible during normal execution but are readable and writable during program/verify. Only the least significant 4 bits of the ID locations are used. In-Circuit Serial ProgrammingTM The PIC16C55X microcontrollers can be serially programmed while in the end application circuit. This is simply done with two lines for clock and data, and three other lines for power, ground, and the programming voltage. This allows customers to manufacture boards with unprogrammed devices, and then program the microcontroller just before shipping the product. This also allows the most recent firmware or a custom firmware to be programmed. The device is placed into a program/verify mode by holding the RB6 and RB7 pins low while raising the MCLR (VPP) pin from VIL to VIHH (see programming specification). RB6 becomes the programming clock and RB7 becomes the programming data. Both RB6 and RB7 are Schmitt Trigger inputs in this mode. After reset, to place the device into programming/verify mode, the program counter (PC) is at location 00h. A 6-bit command is then supplied to the device. Depending on the command, 14-bits of program data are then supplied to or from the device, depending if the command was a load or a read. For complete details of serial programming, please refer to the PIC16C6X/7X Programming Specifications (Literature #DS30228). A typical in-circuit serial programming connection is shown in Figure 7-17. FIGURE 7-17: TYPICAL IN-CIRCUIT SERIAL PROGRAMMING CONNECTION External Connector Signals To Normal Connections PIC16C55X +5V VDD 0V VSS VPP MCLR/VPP CLK RB6 Data I/O RB7 VDD To Normal Connections DS40143C-page 50 Preliminary 1998 Microchip Technology Inc. PIC16C55X 8.0 INSTRUCTION SET SUMMARY Each PIC16C55X instruction is a 14-bit word divided into an OPCODE which specifies the instruction type and one or more operands which further specify the operation of the instruction. The PIC16C55X instruction set summary in Table 8-2 lists byte-oriented, bit-oriented, and literal and control operations. Table 8-1 shows the opcode field descriptions. For byte-oriented instructions, 'f' represents a file register designator and 'd' represents a destination designator. The file register designator specifies which file register is to be used by the instruction. The destination designator specifies where the result of the operation is to be placed. If 'd' is zero, the result is placed in the W register. If 'd' is one, the result is placed in the file register specified in the instruction. For bit-oriented instructions, 'b' represents a bit field designator which selects the number of the bit affected by the operation, while 'f' represents the number of the file in which the bit is located. For literal and control operations, 'k' represents an eight or eleven bit constant or literal value. TABLE 8-1: OPCODE FIELD DESCRIPTIONS Field The instruction set is highly orthogonal and is grouped into three basic categories: * Byte-oriented operations * Bit-oriented operations * Literal and control operations All instructions are executed within one single instruction cycle, unless a conditional test is true or the program counter is changed as a result of an instruction. In this case, the execution takes two instruction cycles with the second cycle executed as a NOP. One instruction cycle consists of four oscillator periods. Thus, for an oscillator frequency of 4 MHz, the normal instruction execution time is 1 s. If a conditional test is true or the program counter is changed as a result of an instruction, the instruction execution time is 2 s. Table 8-1 lists the instructions recognized by the MPASM assembler. Figure 8-1 shows the three general formats that the instructions can have. Note: All examples use the following format to represent a hexadecimal number: Description 0xhh Register file address (0x00 to 0x7F) Working register (accumulator) Bit address within an 8-bit file register Literal field, constant data or label Don't care location (= 0 or 1) The assembler will generate code with x = 0. It is the recommended form of use for compatibility with all Microchip software tools. d Destination select; d = 0: store result in W, d = 1: store result in file register f. Default is d = 1 label Label name TOS Top of Stack PC Program Counter f W b k x where h signifies a hexadecimal digit. FIGURE 8-1: PCLATH Program Counter High Latch GIE WDT TO PD dest [ ] ( ) <> To maintain upward compatibility with future PICmicro(R) products, do not use the OPTION and TRIS instructions. Global Interrupt Enable bit Watchdog Timer/Counter Time-out bit Power-down bit Destination either the W register or the specified register file location Options GENERAL FORMAT FOR INSTRUCTIONS Byte-oriented file register operations 13 8 7 6 OPCODE d f (FILE #) 0 d = 0 for destination W d = 1 for destination f f = 7-bit file register address Bit-oriented file register operations 13 10 9 7 6 OPCODE b (BIT #) f (FILE #) 0 b = 3-bit bit address f = 7-bit file register address Literal and control operations General 13 Contents 8 7 OPCODE Assigned to 0 k (literal) k = 8-bit immediate value Register bit field In the set of CALL and GOTO instructions only italics User defined term (font is courier) 13 11 OPCODE 10 0 k (literal) k = 11-bit immediate value 1998 Microchip Technology Inc. Preliminary DS40143C-page 51 PIC16C55X TABLE 8-2: PIC16C55X INSTRUCTION SET Mnemonic, Operands Description Cycles 14-Bit Opcode MSb LSb Status Affected Notes BYTE-ORIENTED FILE REGISTER OPERATIONS ADDWF ANDWF CLRF CLRW COMF DECF DECFSZ INCF INCFSZ IORWF MOVF MOVWF NOP RLF RRF SUBWF SWAPF XORWF f, d f, d f f, d f, d f, d f, d f, d f, d f, d f f, d f, d f, d f, d f, d Add W and f AND W with f Clear f Clear W Complement f Decrement f Decrement f, Skip if 0 Increment f Increment f, Skip if 0 Inclusive OR W with f Move f Move W to f No Operation Rotate Left f through Carry Rotate Right f through Carry Subtract W from f Swap nibbles in f Exclusive OR W with f 1 1 1 1 1 1 1(2) 1 1(2) 1 1 1 1 1 1 1 1 1 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 00 0111 0101 0001 0001 1001 0011 1011 1010 1111 0100 1000 0000 0000 1101 1100 0010 1110 0110 dfff dfff lfff 0000 dfff dfff dfff dfff dfff dfff dfff lfff 0xx0 dfff dfff dfff dfff dfff ffff ffff ffff 0011 ffff ffff ffff ffff ffff ffff ffff ffff 0000 ffff ffff ffff ffff ffff 1 1 1 (2) 1 (2) 01 01 01 01 00bb 01bb 10bb 11bb bfff bfff bfff bfff ffff ffff ffff ffff 1 1 2 1 2 1 1 2 2 2 1 1 1 11 11 10 00 10 11 11 00 11 00 00 11 11 111x 1001 0kkk 0000 1kkk 1000 00xx 0000 01xx 0000 0000 110x 1010 kkkk kkkk kkkk 0110 kkkk kkkk kkkk 0000 kkkk 0000 0110 kkkk kkkk kkkk kkkk kkkk 0100 kkkk kkkk kkkk 1001 kkkk 1000 0011 kkkk kkkk C,DC,Z Z Z Z Z Z Z Z Z C C C,DC,Z Z 1,2 1,2 2 1,2 1,2 1,2,3 1,2 1,2,3 1,2 1,2 1,2 1,2 1,2 1,2 1,2 BIT-ORIENTED FILE REGISTER OPERATIONS BCF BSF BTFSC BTFSS f, b f, b f, b f, b Bit Clear f Bit Set f Bit Test f, Skip if Clear Bit Test f, Skip if Set 1,2 1,2 3 3 LITERAL AND CONTROL OPERATIONS ADDLW ANDLW CALL CLRWDT GOTO IORLW MOVLW RETFIE RETLW RETURN SLEEP SUBLW XORLW k k k k k k k k k Add literal and W AND literal with W Call subroutine Clear Watchdog Timer Go to address Inclusive OR literal with W Move literal to W Return from interrupt Return with literal in W Return from Subroutine Go into standby mode Subtract W from literal Exclusive OR literal with W C,DC,Z Z TO,PD Z TO,PD C,DC,Z Z Note 1: When an I/O register is modified as a function of itself ( e.g., MOVF PORTB, 1), the value used will be that value present on the pins themselves. For example, if the data latch is '1' for a pin configured as input and is driven low by an external device, the data will be written back with a '0'. 2: If this instruction is executed on the TMR0 register (and, where applicable, d = 1), the prescaler will be cleared if assigned to the Timer0 Module. 3: If Program Counter (PC) is modified or a conditional test is true, the instruction requires two cycles. The second cycle is executed as a NOP. DS40143C-page 52 Preliminary 1998 Microchip Technology Inc. PIC16C55X 8.1 Instruction Descriptions ANDLW AND Literal with W Syntax: [ label ] ANDLW 0 k 255 Operands: 0 k 255 (W) + k (W) Operation: (W) .AND. (k) (W) C, DC, Z Status Affected: Z ADDLW Add Literal and W Syntax: [ label ] ADDLW Operands: Operation: Status Affected: Encoding: 11 k 111x kkkk kkkk Encoding: 11 k 1001 kkkk kkkk Description: The contents of the W register are added to the eight bit literal 'k' and the result is placed in the W register. Description: The contents of W register are AND'ed with the eight bit literal 'k'. The result is placed in the W register. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Example ADDLW Example 0x15 = W 0x10 ADDWF = = 0xA3 After Instruction After Instruction W 0x5F Before Instruction Before Instruction W ANDLW W 0x25 Add W and f ANDWF = 0x03 AND W with f Syntax: [ label ] ADDWF Syntax: [ label ] ANDWF Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (W) + (f) (dest) Operation: (W) .AND. (f) (dest) Status Affected: C, DC, Z Status Affected: Z Encoding: 00 f,d 0111 dfff ffff Encoding: 00 f,d 0101 dfff ffff Description: Add the contents of the W register with register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Description: AND the W register with register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Words: 1 Cycles: 1 Cycles: 1 Example ADDWF FSR, 0 Example Before Instruction W = FSR = 1998 Microchip Technology Inc. FSR, 1 Before Instruction 0x17 0xC2 W = FSR = After Instruction W = FSR = ANDWF 0x17 0xC2 After Instruction 0xD9 0xC2 W = FSR = Preliminary 0x17 0x02 DS40143C-page 53 PIC16C55X BCF Bit Clear f Syntax: [ label ] BCF Syntax: [ label ] BTFSC f,b Operands: 0 f 127 0b7 Operands: 0 f 127 0b7 Operation: 0 (f<b>) Operation: skip if (f<b>) = 0 Status Affected: None Status Affected: None Encoding: 01 BTFSC f,b 00bb bfff ffff Description: Bit 'b' in register 'f' is cleared. Words: 1 Cycles: 1 Example BCF Encoding: FLAG_REG = 0x47 10bb bfff ffff If bit 'b' in register 'f' is '0' then the next instruction is skipped. If bit 'b' is '0' then the next instruction fetched during the current instruction execution is discarded, and a NOP is executed instead, making this a two-cycle instruction. Words: 1 Cycles: 1(2) Before Instruction FLAG_REG = 0xC7 01 Description: FLAG_REG, 7 After Instruction Bit Test, Skip if Clear Example HERE FALSE TRUE BTFSC GOTO * * * FLAG,1 PROCESS_CODE Before Instruction PC = address HERE After Instruction if FLAG<1> = 0, PC = address TRUE if FLAG<1>=1, PC = address FALSE BSF Bit Set f Syntax: [ label ] BSF Operands: 0 f 127 0b7 Operation: 1 (f<b>) Status Affected: None Encoding: 01 f,b 01bb bfff Description: Bit 'b' in register 'f' is set. Words: 1 Cycles: 1 Example BSF FLAG_REG, ffff 7 Before Instruction FLAG_REG = 0x0A After Instruction FLAG_REG = 0x8A DS40143C-page 54 Preliminary 1998 Microchip Technology Inc. PIC16C55X BTFSS Bit Test f, Skip if Set CLRF Clear f Syntax: [ label ] BTFSS f,b Syntax: [ label ] CLRF Operands: 0 f 127 0b<7 Operands: 0 f 127 Operation: Operation: skip if (f<b>) = 1 00h (f) 1Z Status Affected: None Status Affected: Z Encoding: Description: 01 11bb bfff ffff If bit 'b' in register 'f' is '1' then the next instruction is skipped. If bit 'b' is '1', then the next instruction fetched during the current instruction execution, is discarded and a NOP is executed instead, making this a two-cycle instruction. Words: 1 Cycles: 1(2) Example HERE FALSE TRUE Encoding: 00 f 0001 1fff ffff Description: The contents of register 'f' are cleared and the Z bit is set. Words: 1 Cycles: 1 Example CLRF FLAG_REG Before Instruction FLAG_REG BTFSS GOTO * * * = 0x5A = = 0x00 1 After Instruction FLAG,1 PROCESS_CODE FLAG_REG Z Before Instruction PC = address HERE After Instruction if FLAG<1> = 0, PC = address FALSE if FLAG<1> = 1, PC = address TRUE CALL Call Subroutine CLRW Clear W Syntax: [ label ] CALL k Syntax: [ label ] CLRW Operands: 0 k 2047 Operands: None Operation: (PC)+ 1 TOS, k PC<10:0>, (PCLATH<4:3>) PC<12:11> Operation: 00h (W) 1Z Status Affected: Z Status Affected: None Encoding: Encoding: Description: 10 kkkk kkkk Call Subroutine. First, return address (PC+1) is pushed onto the stack. The eleven bit immediate address is loaded into PC bits <10:0>. The upper bits of the PC are loaded from PCLATH. CALL is a two-cycle instruction. Words: 1 Cycles: 2 Example 0kkk 00 0001 0000 0011 Description: W register is cleared. Zero bit (Z) is set. Words: 1 Cycles: 1 Example CLRW Before Instruction W HERE CALL = 0x5A After Instruction THERE W Z Before Instruction = = 0x00 1 PC = Address HERE After Instruction PC = Address THERE TOS = Address HERE+1 1998 Microchip Technology Inc. Preliminary DS40143C-page 55 PIC16C55X CLRWDT Clear Watchdog Timer DECF Decrement f Syntax: [ label ] CLRWDT Syntax: [ label ] DECF f,d Operands: None Operands: Operation: 00h WDT 0 WDT prescaler, 1 TO 1 PD 0 f 127 d [0,1] Operation: (f) - 1 (dest) Status Affected: Z Status Affected: TO, PD Encoding: Description: Encoding: 00 0000 0110 0100 CLRWDT instruction resets the Watchdog Timer. It also resets the prescaler of the WDT. Status bits TO and PD are set. Words: 1 Cycles: 1 Example 00 0011 dfff Description: Decrement register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Cycles: 1 Example DECF CNT, 1 Before Instruction CLRWDT CNT Z Before Instruction WDT counter = WDT counter = WDT prescaler= TO = PD = COMF Complement f Syntax: [ label ] COMF Operands: = = 0x01 0 = = 0x00 1 After Instruction ? CNT Z After Instruction 0x00 0 1 1 DECFSZ Decrement f, Skip if 0 Syntax: [ label ] DECFSZ f,d 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (f) (dest) Operation: (f) - 1 (dest); Status Affected: Z Status Affected: None Encoding: 00 1001 f,d dfff ffff Description: The contents of register 'f' are complemented. If 'd' is 0 the result is stored in W. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Cycles: 1 Example ffff COMF REG1,0 Before Instruction REG1 = 0x13 = = 0x13 0xEC After Instruction REG1 W Encoding: 00 1011 skip if result = 0 dfff ffff Description: The contents of register 'f' are decremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. If the result is 0, the next instruction, which is already fetched, is discarded. A NOP is executed instead making it a two-cycle instruction. Words: 1 Cycles: 1(2) Example HERE DECFSZ GOTO CONTINUE * * * CNT, 1 LOOP Before Instruction PC = address HERE After Instruction CNT if CNT PC if CNT PC DS40143C-page 56 Preliminary = = = = CNT - 1 0, address CONTINUE 0, address HERE+1 1998 Microchip Technology Inc. PIC16C55X GOTO Unconditional Branch INCFSZ Increment f, Skip if 0 Syntax: [ label ] Syntax: [ label ] Operands: 0 k 2047 Operands: Operation: k PC<10:0> PCLATH<4:3> PC<12:11> 0 f 127 d [0,1] Operation: (f) + 1 (dest), skip if result = 0 None Status Affected: None Status Affected: Encoding: GOTO k 10 1kkk kkkk kkkk Description: GOTO is an unconditional branch. The eleven bit immediate value is loaded into PC bits <10:0>. The upper bits of PC are loaded from PCLATH<4:3>. GOTO is a two-cycle instruction. Words: 1 Cycles: 2 Example GOTO THERE After Instruction PC = Address THERE Encoding: 00 INCFSZ f,d 1111 dfff ffff Description: The contents of register 'f' are incremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. If the result is 0, the next instruction, which is already fetched, is discarded. A NOP is executed instead making it a two-cycle instruction. Words: 1 Cycles: 1(2) Example HERE INCFSZ GOTO CONTINUE * * * CNT, LOOP 1 Before Instruction PC = address HERE After Instruction CNT = if CNT= PC = if CNT PC = CNT + 1 0, address CONTINUE 0, address HERE +1 INCF Increment f IORLW Inclusive OR Literal with W Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 k 255 (f) + 1 (dest) Operation: (W) .OR. k (W) Operation: Status Affected: Z Status Affected: Z Encoding: Description: INCF f,d Encoding: 00 1010 dfff ffff The contents of register 'f' are incremented. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. kkkk Words: 1 1 1 Cycles: 1 Example IORLW 0x35 Before Instruction CNT, 1 W Before Instruction CNT Z kkkk The contents of the W register is OR'ed with the eight bit literal 'k'. The result is placed in the W register. Words: INCF 1000 Description: Cycles: Example 11 IORLW k = 0x9A After Instruction = = 0xFF 0 = = 0x00 1 W Z = = 0xBF 1 After Instruction CNT Z 1998 Microchip Technology Inc. Preliminary DS40143C-page 57 PIC16C55X IORWF Inclusive OR W with f MOVF Move f Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 f 127 d [0,1] Operation: (W) .OR. (f) (dest) Operation: (f) (dest) Status Affected: Z Status Affected: Z Encoding: 00 IORWF f,d 0100 dfff ffff Description: Inclusive OR the W register with register 'f'. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. Words: 1 Cycles: 1 Example IORWF RESULT, 0 Before Instruction RESULT = W = 0x13 0x91 Encoding: MOVF f,d 00 1000 The contents of register f is moved to a destination dependant upon the status of d. If d = 0, destination is W register. If d = 1, the destination is file register f itself. d = 1 is useful to test a file register since status flag Z is affected. Words: 1 Cycles: 1 Example MOVF FSR, 0 After Instruction RESULT = W = Z = 0x13 0x93 1 W = value in FSR register Z =1 MOVLW Move Literal to W MOVWF Move W to f Syntax: [ label ] Syntax: [ label ] Operands: 0 k 255 Operands: 0 f 127 Operation: k (W) Operation: (W) (f) Status Affected: None Status Affected: None 11 MOVLW k 00xx kkkk kkkk Description: The eight bit literal 'k' is loaded into W register. The don't cares will assemble as 0's. Words: 1 Cycles: 1 Example Encoding: 1fff ffff Words: 1 Cycles: 1 MOVWF OPTION Before Instruction After Instruction = 0000 f Move data from W register to register 'f'. 0x5A W 00 MOVWF Description: Example MOVLW ffff Description: After Instruction Encoding: dfff OPTION = W = 0x5A 0xFF 0x4F After Instruction OPTION = W = DS40143C-page 58 Preliminary 0x4F 0x4F 1998 Microchip Technology Inc. PIC16C55X NOP No Operation RETFIE Return from Interrupt Syntax: [ label ] Syntax: [ label ] Operands: None Operands: None Operation: No operation Operation: Status Affected: None TOS PC, 1 GIE Status Affected: None Encoding: 00 NOP 0000 0xx0 0000 RETFIE Description: No operation. Encoding: Words: 1 Description: Cycles: 1 Return from Interrupt. Stack is POPed and Top of Stack (TOS) is loaded in the PC. Interrupts are enabled by setting Global Interrupt Enable bit, GIE (INTCON<7>). This is a two-cycle instruction. Words: 1 Cycles: 2 Example 00 NOP Example 0000 0000 1001 RETFIE After Interrupt PC = GIE = TOS 1 OPTION Load Option Register RETLW Return with Literal in W Syntax: [ label ] Syntax: [ label ] Operands: None Operands: 0 k 255 Operation: (W) OPTION Operation: k (W); TOS PC Status Affected: None OPTION Status Affected: None Encoding: Description: 00 0000 0110 0010 The contents of the W register are loaded in the OPTION register. This instruction is supported for code compatibility with PIC16C5X products. Since OPTION is a readable/writable register, the user can directly address it. Encoding: RETLW k 11 01xx kkkk Description: The W register is loaded with the eight bit literal 'k'. The program counter is loaded from the top of the stack (the return address). This is a two-cycle instruction. 1 Words: 1 Words: Cycles: 1 Cycles: 2 Example CALL TABLE Example kkkk To maintain upward compatibility with future PICmicroTM products, do not use this instruction. * value * TABLE * ADDWF RETLW RETLW * * * RETLW ;W contains table ;offset value ;W now has table PC k1 k2 ;W = offset ;Begin table ; kn ; End of table Before Instruction W = 0x07 After Instruction W 1998 Microchip Technology Inc. Preliminary = value of k8 DS40143C-page 59 PIC16C55X RETURN Return from Subroutine Syntax: [ label ] Operands: None Operation: TOS PC Status Affected: None Encoding: Description: RETURN 00 0000 0000 1000 Return from subroutine. The stack is POPed and the top of the stack (TOS) is loaded into the program counter. This is a two cycle instruction. Words: 1 Cycles: 2 Example RRF Rotate Right f through Carry Syntax: [ label ] Operands: 0 f 127 d [0,1] Operation: See description below Status Affected: C Encoding: Description: RRF f,d 00 1100 dfff ffff The contents of register 'f' are rotated one bit to the right through the Carry Flag. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is placed back in register 'f'. C Register f RETURN After Interrupt PC = TOS Words: 1 Cycles: 1 Example RRF REG1,0 Before Instruction REG1 C = = 1110 0110 0 = = = 1110 0110 0111 0011 0 After Instruction REG1 W C RLF Rotate Left f through Carry SLEEP Syntax: [ label ] Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: None Operation: 00h WDT, 0 WDT prescaler, 1 TO, 0 PD Status Affected: TO, PD RLF f,d Operation: See description below Status Affected: C Encoding: Description: 00 1101 C Words: 1 Cycles: 1 Example dfff ffff The contents of register 'f' are rotated one bit to the left through the Carry Flag. If 'd' is 0 the result is placed in the W register. If 'd' is 1 the result is stored back in register 'f'. RLF Encoding: Before Instruction REG1 C = = 1110 0110 0 = = = 1110 0110 1100 1100 1 0000 0110 0011 Description: The power-down status bit, PD is cleared. Time-out status bit, TO is set. Watchdog Timer and its prescaler are cleared. The processor is put into SLEEP mode with the oscillator stopped. See Section 7.8 for more details. Words: 1 Cycles: 1 Example: SLEEP Register f REG1,0 00 SLEEP After Instruction REG1 W C DS40143C-page 60 Preliminary 1998 Microchip Technology Inc. PIC16C55X SUBLW Subtract W from Literal SUBWF Subtract W from f Syntax: [ label ] Syntax: [ label ] Operands: 0 k 255 Operands: Operation: k - (W) (W) 0 f 127 d [0,1] Status Affected: C, DC, Z Operation: (f) - (W) (dest) Status Affected: C, DC, Z Encoding: 00 Encoding: Description: Words: 11 SUBLW k 110x kkkk kkkk The W register is subtracted (2's complement method) from the eight bit literal 'k'. The result is placed in the W register. 1 Example 1: SUBLW 0x02 Before Instruction W C = = Example 2: = = 1 Cycles: 1 Example 1: 1 ? Example 3: = = REG1 W C 1 1; result is posi- = = REG1 W C 2 ? Example 2: = = = 3 2 ? = = = 1 2 1; result is positive Before Instruction REG1 W C 0 1; result is zero = = = 2 2 ? After Instruction 3 ? REG1 W C After Instruction W = C = tive REG1,1 After Instruction Before Instruction W C SUBWF Before Instruction After Instruction W C ffff Words: Before Instruction W C dfff Subtract (2's complement method) W register from register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. After Instruction W = C = tive 0010 Description: 1 Cycles: SUBWF f,d 0xFF 0; result is nega- Example 3: = = = 0 2 1; result is zero Before Instruction REG1 W C = = = 1 2 ? After Instruction REG1 W C 1998 Microchip Technology Inc. Preliminary = = = 0xFF 2 0; result is negative DS40143C-page 61 PIC16C55X SWAPF Swap Nibbles in f XORLW Exclusive OR Literal with W Syntax: [ label ] SWAPF f,d Syntax: [ label ] Operands: 0 f 127 d [0,1] Operands: 0 k 255 Operation: (f<3:0>) (dest<7:4>), (f<7:4>) (dest<3:0>) Operation: (W) .XOR. k (W) Status Affected: Z Status Affected: None Encoding: Description: Encoding: 00 1110 dfff ffff The upper and lower nibbles of register 'f' are exchanged. If 'd' is 0 the result is placed in W register. If 'd' is 1 the result is placed in register 'f'. 11 1 1 Cycles: 1 Example: XORLW 0xAF Before Instruction 0 W Before Instruction = W = = = 0xB5 After Instruction 0xA5 After Instruction REG1 W = 0x1A 0xA5 0x5A TRIS Load TRIS Register XORWF Exclusive OR W with f Syntax: [ label ] XORWF Operands: 0 f 127 d [0,1] Operation: (W) .XOR. (f) (dest) Status Affected: Z Syntax: [ label ] TRIS Operands: 5f7 Operation: (W) TRIS register f; f Status Affected: None Encoding: Description: 00 0000 0110 0fff The instruction is supported for code compatibility with the PIC16C5X products. Since TRIS registers are readable and writable, the user can directly address them. Words: 1 Cycles: 1 kkkk Words: Cycles: REG1 kkkk The contents of the W register are XOR'ed with the eight bit literal 'k'. The result is placed in the W register. 1 SWAPF REG, 1010 Description: Words: Example XORLW k Example To maintain upward compatibility with future PICmicroTM products, do not use this instruction. Encoding: 00 0110 f,d dfff ffff Description: Exclusive OR the contents of the W register with register 'f'. If 'd' is 0 the result is stored in the W register. If 'd' is 1 the result is stored back in register 'f'. Words: 1 Cycles: 1 Example XORWF REG 1 Before Instruction REG W = = 0xAF 0xB5 = = 0x1A 0xB5 After Instruction REG W DS40143C-page 62 Preliminary 1998 Microchip Technology Inc. PIC16C55X 9.0 DEVELOPMENT SUPPORT 9.1 Development Tools 9.3 The PICmicr microcontrollers are supported with a full range of hardware and software development tools: * MPLABTM-ICE Real-Time In-Circuit Emulator * ICEPIC Low-Cost PIC16C5X and PIC16CXXX In-Circuit Emulator * PRO MATE II Universal Programmer * PICSTART Plus Entry-Level Prototype Programmer * SIMICE * PICDEM-1 Low-Cost Demonstration Board * PICDEM-2 Low-Cost Demonstration Board * PICDEM-3 Low-Cost Demonstration Board * MPASM Assembler * MPLAB SIM Software Simulator * MPLAB-C17 (C Compiler) * Fuzzy Logic Development System (fuzzyTECH-MP) * KEELOQ(R) Evaluation Kits and Programmer 9.2 ICEPIC: Low-Cost PICmicro In-Circuit Emulator ICEPIC is a low-cost in-circuit emulator solution for the Microchip PIC12CXXX, PIC16C5X and PIC16CXXX families of 8-bit OTP microcontrollers. ICEPIC is designed to operate on PC-compatible machines ranging from 386 through Pentium based machines under Windows 3.x, Windows 95, or Windows NT environment. ICEPIC features real time, non-intrusive emulation. 9.4 PRO MATE II: Universal Programmer The PRO MATE II Universal Programmer is a full-featured programmer capable of operating in stand-alone mode as well as PC-hosted mode. PRO MATE II is CE compliant. The PRO MATE II has programmable VDD and VPP supplies which allows it to verify programmed memory at VDD min and VDD max for maximum reliability. It has an LCD display for displaying error messages, keys to enter commands and a modular detachable socket assembly to support various package types. In standalone mode the PRO MATE II can read, verify or program PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices. It can also set configuration and code-protect bits in this mode. MPLAB-ICE: High Performance Universal In-Circuit Emulator with MPLAB IDE The MPLAB-ICE Universal In-Circuit Emulator is intended to provide the product development engineer with a complete microcontroller design tool set for PICmicro microcontrollers (MCUs). MPLAB-ICE is supplied with the MPLAB Integrated Development Environment (IDE), which allows editing, "make" and download, and source debugging from a single environment. Interchangeable processor modules allow the system to be easily reconfigured for emulation of different processors. The universal architecture of the MPLAB-ICE allows expansion to support all new Microchip microcontrollers. The MPLAB-ICE Emulator System has been designed as a real-time emulation system with advanced features that are generally found on more expensive development tools. The PC compatible 386 (and higher) machine platform and Microsoft Windows 3.x or Windows 95 environment were chosen to best make these features available to you, the end user. 9.5 PICSTART Plus Entry Level Development System The PICSTART programmer is an easy-to-use, low-cost prototype programmer. It connects to the PC via one of the COM (RS-232) ports. MPLAB Integrated Development Environment software makes using the programmer simple and efficient. PICSTART Plus is not recommended for production programming. PICSTART Plus supports all PIC12CXXX, PIC14C000, PIC16C5X, PIC16CXXX and PIC17CXX devices with up to 40 pins. Larger pin count devices such as the PIC16C923, PIC16C924 and PIC17C756 may be supported with an adapter socket. PICSTART Plus is CE compliant. MPLAB-ICE is available in two versions. MPLAB-ICE 1000 is a basic, low-cost emulator system with simple trace capabilities. It shares processor modules with the MPLAB-ICE 2000. This is a full-featured emulator system with enhanced trace, trigger, and data monitoring features. Both systems will operate across the entire operating speed reange of the PICmicro MCU. 1998 Microchip Technology Inc. Preliminary DS40143C-page 63 PIC16C55X 9.6 SIMICE Entry-Level Hardware Simulator 9.8 PICDEM-2 Low-Cost PIC16CXX Demonstration Board SIMICE is an entry-level hardware development system designed to operate in a PC-based environment with Microchip's simulator MPLABTM-SIM. Both SIMICE and MPLAB-SIM run under Microchip Technology's MPLAB Integrated Development Environment (IDE) software. Specifically, SIMICE provides hardware simulation for Microchip's PIC12C5XX, PIC12CE5XX, and PIC16C5X families of PICmicro 8-bit microcontrollers. SIMICE works in conjunction with MPLAB-SIM to provide non-real-time I/O port emulation. SIMICE enables a developer to run simulator code for driving the target system. In addition, the target system can provide input to the simulator code. This capability allows for simple and interactive debugging without having to manually generate MPLAB-SIM stimulus files. SIMICE is a valuable debugging tool for entry-level system development. The PICDEM-2 is a simple demonstration board that supports the PIC16C62, PIC16C64, PIC16C65, PIC16C73 and PIC16C74 microcontrollers. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-2 board, on a PRO MATE II programmer or PICSTART-Plus, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-2 board to test firmware. Additional prototype area has been provided to the user for adding additional hardware and connecting it to the microcontroller socket(s). Some of the features include a RS-232 interface, push-button switches, a potentiometer for simulated analog input, a Serial EEPROM to demonstrate usage of the I2C bus and separate headers for connection to an LCD module and a keypad. 9.7 9.9 PICDEM-1 Low-Cost PICmicro Demonstration Board The PICDEM-1 is a simple board which demonstrates the capabilities of several of Microchip's microcontrollers. The microcontrollers supported are: PIC16C5X (PIC16C54 to PIC16C58A), PIC16C61, PIC16C62X, PIC16C71, PIC16C8X, PIC17C42, PIC17C43 and PIC17C44. All necessary hardware and software is included to run basic demo programs. The users can program the sample microcontrollers provided with the PICDEM-1 board, on a PRO MATE II or PICSTART-Plus programmer, and easily test firmware. The user can also connect the PICDEM-1 board to the MPLAB-ICE emulator and download the firmware to the emulator for testing. Additional prototype area is available for the user to build some additional hardware and connect it to the microcontroller socket(s). Some of the features include an RS-232 interface, a potentiometer for simulated analog input, push-button switches and eight LEDs connected to PORTB. DS40143C-page 64 PICDEM-3 Low-Cost PIC16CXXX Demonstration Board The PICDEM-3 is a simple demonstration board that supports the PIC16C923 and PIC16C924 in the PLCC package. It will also support future 44-pin PLCC microcontrollers with a LCD Module. All the necessary hardware and software is included to run the basic demonstration programs. The user can program the sample microcontrollers provided with the PICDEM-3 board, on a PRO MATE II programmer or PICSTART Plus with an adapter socket, and easily test firmware. The MPLAB-ICE emulator may also be used with the PICDEM-3 board to test firmware. Additional prototype area has been provided to the user for adding hardware and connecting it to the microcontroller socket(s). Some of the features include an RS-232 interface, push-button switches, a potentiometer for simulated analog input, a thermistor and separate headers for connection to an external LCD module and a keypad. Also provided on the PICDEM-3 board is an LCD panel, with 4 commons and 12 segments, that is capable of displaying time, temperature and day of the week. The PICDEM-3 provides an additional RS-232 interface and Windows 3.1 software for showing the demultiplexed LCD signals on a PC. A simple serial interface allows the user to construct a hardware demultiplexer for the LCD signals. Preliminary 1998 Microchip Technology Inc. PIC16C55X 9.10 MPLAB Integrated Development Environment Software 9.12 The MPLAB IDE Software brings an ease of software development previously unseen in the 8-bit microcontroller market. MPLAB is a windows based application which contains: * A full featured editor * Three operating modes - editor - emulator - simulator * A project manager * Customizable tool bar and key mapping * A status bar with project information * Extensive on-line help Software Simulator (MPLAB-SIM) The MPLAB-SIM Software Simulator allows code development in a PC host environment. It allows the user to simulate the PICmicro series microcontrollers on an instruction level. On any given instruction, the user may examine or modify any of the data areas or provide external stimulus to any of the pins. The input/output radix can be set by the user and the execution can be performed in; single step, execute until break, or in a trace mode. MPLAB-SIM fully supports symbolic debugging using MPLAB-C17 and MPASM. The Software Simulator offers the low cost flexibility to develop and debug code outside of the laboratory environment making it an excellent multi-project software development tool. MPLAB allows you to: 9.13 * Edit your source files (either assembly or `C') * One touch assemble (or compile) and download to PICmicro tools (automatically updates all project information) * Debug using: - source files - absolute listing file The MPLAB-C17 Code Development System is a complete ANSI `C' compiler and integrated development environment for Microchip's PIC17CXXX family of microcontrollers. The compiler provides powerful integration capabilities and ease of use not found with other compilers. The ability to use MPLAB with Microchip's simulator allows a consistent platform and the ability to easily switch from the low cost simulator to the full featured emulator with minimal retraining due to development tools. 9.11 Assembler (MPASM) The MPASM Universal Macro Assembler is a PC-hosted symbolic assembler. It supports all microcontroller series including the PIC12C5XX, PIC14000, PIC16C5X, PIC16CXXX, and PIC17CXX families. MPASM offers full featured Macro capabilities, conditional assembly, and several source and listing formats. It generates various object code formats to support Microchip's development tools as well as third party programmers. MPASM allows full symbolic debugging from MPLAB-ICE, Microchip's Universal Emulator System. MPASM has the following features to assist in developing software for specific use applications. * Provides translation of Assembler source code to object code for all Microchip microcontrollers. * Macro assembly capability. * Produces all the files (Object, Listing, Symbol, and special) required for symbolic debug with Microchip's emulator systems. * Supports Hex (default), Decimal and Octal source and listing formats. MPLAB-C17 Compiler For easier source level debugging, the compiler provides symbol information that is compatible with the MPLAB IDE memory display. 9.14 Fuzzy Logic Development System (fuzzyTECH-MP) fuzzyTECH-MP fuzzy logic development tool is available in two versions - a low cost introductory version, MP Explorer, for designers to gain a comprehensive working knowledge of fuzzy logic system design; and a full-featured version, fuzzyTECH-MP, Edition for implementing more complex systems. Both versions include Microchip's fuzzyLAB demonstration board for hands-on experience with fuzzy logic systems implementation. 9.15 SEEVAL Evaluation and Programming System The SEEVAL SEEPROM Designer's Kit supports all Microchip 2-wire and 3-wire Serial EEPROMs. The kit includes everything necessary to read, write, erase or program special features of any Microchip SEEPROM product including Smart Serials and secure serials. The Total Endurance Disk is included to aid in trade-off analysis and reliability calculations. The total kit can significantly reduce time-to-market and result in an optimized system. MPASM provides a rich directive language to support programming of the PICmicro. Directives are helpful in making the development of your assemble source code shorter and more maintainable. 1998 Microchip Technology Inc. Preliminary DS40143C-page 65 PIC16C55X 9.16 KEELOQ Evaluation and Programming Tools KEELOQ evaluation and programming tools support Microchips HCS Secure Data Products. The HCS evaluation kit includes an LCD display to show changing codes, a decoder to decode transmissions, and a programming interface to program test transmitters. DS40143C-page 66 Preliminary 1998 Microchip Technology Inc. Emulator Products u u ICEPIC Low-Cost In-Circuit Emulator MPLAB Integrated Development Environment u u PIC16C5X PIC16CXXX PIC16C6X PIC16C7XX PIC16C8X PIC16C9XX PIC17C4X PIC17C7XX u u u u u u u u u u u u u u u u u u MPLAB C17* Compiler fuzzyTECH-MP Explorer/Edition Fuzzy Logic Dev. Tool u u u u u u u u u u u u u u Programmers u PICSTARTPlus Low-Cost Universal Dev. Kit u u u u u u u u u u PRO MATE II Universal Programmer u u u u u u u u u u u KEELOQ Programmer PICDEM-1 DS40143C-page 67 PICDEM-2 PICDEM-3 u u u u u u u u u u u KEELOQ(R) Evaluation Kit u KEELOQ Transponder Kit u PIC16C55X SIMICE u u SEEVAL Designers Kit PICDEM-14A HCS200 HCS300 HCS301 u Total Endurance Software Model Demo Boards 24CXX 25CXX 93CXX DEVELOPMENT TOOLS FROM MICROCHIP Preliminary Software Tools PIC14000 TABLE 9-1: 1998 Microchip Technology Inc. MPLABTM-ICE PIC12C5XX PIC16C55X NOTES: DS40143C-page 68 Preliminary 1998 Microchip Technology Inc. PIC16C55X 10.0 ELECTRICAL SPECIFICATIONS Absolute Maximum Ratings Ambient Temperature under bias ............................................................................................................. -40 to +125C Storage Temperature................................................................................................................................ -65 to +150C Voltage on any pin with respect to VSS (except VDD and MCLR)...................................................... -0.6V to VDD +0.6V Voltage on VDD with respect to VSS ............................................................................................................... 0 to +7.5V Voltage on MCLR with respect to VSS (Note 2)................................................................................................. 0 to +14V Total power Dissipation (Note 1) ...............................................................................................................................1.0W Maximum Current out of VSS pin...........................................................................................................................300 mA Maximum Current into VDD pin..............................................................................................................................250 mA Input Clamp Current, IIK (VI<0 or VI> VDD) ...................................................................................................................... 20 mA Output Clamp Current, IOK (V0 <0 or V0>VDD) ............................................................................................................... 20 mA Maximum Output Current sunk by any I/O pin ........................................................................................................25 mA Maximum Output Current sourced by any I/O pin ...................................................................................................25 mA Maximum Current sunk by PORTA and PORTB ...................................................................................................200 mA Maximum Current sourced by PORTA and PORTB ..............................................................................................200 mA Note 1: Power dissipation is calculated as follows: PDIS = VDD x {IDD - IOH} + {(VDD-VOH) x IOH} + (VOl x IOL) NOTICE: Stresses above those listed under "Absolute Maximum Ratings" may cause permanent damage to the device. This is a stress rating only and functional operation of the device at those or any other conditions above those indicated in the operation listings of this specification is not implied. Exposure to maximum rating conditions for extended periods may affect device reliability. 1998 Microchip Technology Inc. Preliminary DS40143C-page 69 PIC16C55X TABLE 10-1: OSC CROSS REFERENCE OF DEVICE SPECS FOR OSCILLATOR CONFIGURATIONS AND FREQUENCIES OF OPERATION (COMMERCIAL DEVICES) PIC16C55X-04 PIC16C55X-20 PIC16LC55X-04 PIC16C55X JW Devices RC VDD: 3.0V to 5.5V IDD: 3.3 mA max.@5.5V IPD: 20 A max. @4.0V Freq: 4.0 MHz max. VDD: 4.5V to 5.5V IDD: 1.8 mA typ. @5.5V IPD: 1.0 A typ. @4.5V Freq: 4.0 MHz max. VDD: 2.5V to 5.5V IDD: 1.4 mA typ. @3.0V IPD: 0.7 A typ. @3.0V Freq: 4.0 MHz max. VDD: 3.0V to 5.5V IDD: 3.3 mA max. @5.5V IPD: 20 A max. @4.0V Freq: 4.0 MHz max. XT VDD: 3.0V to 5.5V IDD: 3.3 mA max.@5.5V IPD: 20 A max. @4.0V Freq: 4.0 MHz max. VDD: 4.5V to 5.5V IDD: 1.8 mA typ. @5.5V IPD: 1.0 A typ. @4.5V Freq: 4.0 MHz max. VDD: 2.5V to 5.5V IDD: 1.4 mA typ. @3.0V IPD: 0.7 A typ. @3.0V Freq: 4.0 MHz max. VDD: 3.0V to 5.5V IDD: 3.3 mA max. @5.5V IPD: 20 A max. @4.0V Freq: 4.0 MHz max. HS VDD: 4.5V to 5.5V IDD: 9.0 mA typ. @5.5V IPD: 1.0 A typ. @4.0V Freq: 4.0 MHz max. VDD: 4.5V to 5.5V IDD: 20 mA max. @5.5V IPD: 1.0 A typ. @4.5V Freq: 20 MHz max. LP VDD: 3.0V to 5.5V IDD: 35 A typ. @32 kHz, 3.0V IPD: 1.0 A typ. @4.0 V Freq: 200 kHz maxi. Do not use in HS mode Do not use in LP mode VDD: 2.5V to 5.5V IDD: 32 A max. @32 kHz, 3.0V IPD: 9.0 A max. @3.0V Freq: 200 kHz max. VDD: 4.5V to 5.5V IDD: 20 mA max.@5.5V IPD: 1.0 A typ. @4.5V Freq: 20 MHz max. VDD: 2.5V to 5.5V IDD: 32 A max. @32 kHz, 3.0V IPD: 9.0 A max. @3.0V Freq: 200 kHz max. The shaded sections indicate oscillator selections which are tested for functionality, but not for MIN/MAX specifications. It is recommended that the user select the device type that ensures the specifications required. DS40143C-page 70 Preliminary 1998 Microchip Technology Inc. PIC16C55X (A) 10.1 DC CHARACTERISTICS: Param No. Sym D001 VDD D001A D002 VDR PIC16C55X-04 (Commercial, Industrial, Extended) PIC16C55X-20 (Commercial, Industrial, Extended) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial and -40C TA +125C for extended Characteristic Min Typ Max Units 3.0 4.5 - 1.5* 5.5 5.5 - V V V - VSS - V 0.05* - - - 1.8 3.3 D010A - 35 70 D013 - 9.0 20 Power Down Current (Note 3) - 1.0 WDT Current (Note 5) - 6.0 2.5 15 20 D003 VPOR D004 SVDD D010 IDD D020 IPD IWDT * Note 1: 2: 3: 4: 5: Supply Voltage RAM Data Retention Voltage (Note 1) VDD start voltage to ensure Power-on Reset VDD rise rate to ensure Power-on Reset Supply Current (Note 2) Conditions XT, RC and LP osc configuration HS osc configuration Device in SLEEP mode See section on power-on reset for details V/ms See section on power-on reset for details mA XT and RC osc configuration FOSC = 4 MHz, VDD = 5.5V, WDT disabled (Note 4) A LP osc configuration, PIC16C55X-04 only FOSC = 32 kHz, VDD = 4.0V, WDT disabled mA HS osc configuration FOSC = 20 MHz, VDD = 5.5V, WDT disabled A VDD=4.0V, WDT disabled A (+85C to +125C) A VDD=4.0V (+85C to +125C) These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C, unless otherwise stated. These parameters are for design guidance only and are not tested. This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1 = external square wave, from rail to rail; all I/O pins configured as input, pulled to VDD, MCLR = VDD; WDT enabled/disabled as specified. The power down current in SLEEP mode does not depend on the oscillator type. Power down current is measured with the part in SLEEP mode, with all I/O pins configured as input and tied to VDD or VSS. For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula Ir = VDD/2Rext (mA) with Rext in k. The current is the additional current consumed when this peripheral is enabled. This current should be added to the base IDD or IPD measurement. 1998 Microchip Technology Inc. Preliminary DS40143C-page 71 PIC16C55X 10.2 DC CHARACTERISTICS: Param No. Sym Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial and -40C TA +125C for extended Characteristic Min Typ Max Units D001 VDD Supply Voltage D002 VDR D003 VPOR D004 SVDD D010 IDD RAM Data Retention Voltage (Note 1) VDD start voltage to ensure Power-on Reset VDD rise rate to ensure Power-on Reset Supply Current (Note 2) D010A D020 * Note 1: 2: 3: 4: 5: PIC16LC55X-04 (Commercial, Industrial, Extended) 3.0 2.5 - - V 1.5* 5.5 5.5 - - VSS - V 0.05* - - - 1.4 2.5 - 26 53 V Conditions XT and RC osc configuration LP osc configuration Device in SLEEP mode See section on Power-on Reset for details V/ms See section on Power-on Reset for details mA XT and RC osc configuration FOSC = 2.0 MHz, VDD = 3.0V, WDT disabled (Note 4) A LP osc configuration FOSC = 32 kHz, VDD = 3.0V, WDT disabled A VDD=3.0V, WDT disabled A VDD=3.0V IPD Power Down Current (Note 3) - 0.7 2 IWDT WDT Current (Note 5) - 6.0 15 These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C, unless otherwise stated. These parameters are for design guidance only and are not tested. This is the limit to which VDD can be lowered in SLEEP mode without losing RAM data. The supply current is mainly a function of the operating voltage and frequency. Other factors such as I/O pin loading and switching rate, oscillator type, internal code execution pattern, and temperature also have an impact on the current consumption. The test conditions for all IDD measurements in active operation mode are: OSC1=external square wave, from rail to rail; all I/O pins configured as input, pulled to VDD, MCLR = VDD; WDT enabled/disabled as specified. The power down current in SLEEP mode does not depend on the oscillator type. Power down current is measured with the part in SLEEP mode, with all I/O pins configured as input and tied to VDD or VSS. For RC osc configuration, current through Rext is not included. The current through the resistor can be estimated by the formula Ir = VDD/2Rext (mA) with Rext in k. The current is the additional current consumed when this peripheral is enabled. This current should be added to the base IDD or IPD measurement. DS40143C-page 72 Preliminary 1998 Microchip Technology Inc. PIC16C55X 10.3 DC CHARACTERISTICS: PIC16C55X (Commercial, Industrial, Extended) PIC16LC55X (Commercial, Industrial, Extended) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial and -40C TA +125C for automotive Operating voltage VDD range as described in DC spec Table 10-1 Param. Sym No. VIL D030 D031 D032 D033 VIH D040 D041 D042 D043 D043A IPURB D070 IIL D060 D061 D063 Characteristic Input Low Voltage I/O ports with TTL buffer Min Typ Max VSS - 0.8V 0.15VDD 0.2VDD 0.2VDD with Schmitt Trigger input VSS MCLR, RA4/T0CKI,OSC1 (in Vss RC mode) OSC1 (in XT* and HS) Vss 0.3VDD OSC1 (in LP*) Vss - 0.6VDD-1.0 Input High Voltage I/O ports with TTL buffer 2.0V VDD with Schmitt Trigger input 0.25VDD VDD + 0.8V 0.8VDD VDD MCLR RA4/T0CKI OSC1 (XT*, HS and LP*) 0.7VDD VDD OSC1 (in RC mode) 0.9VDD PORTB weak pull-up current 50 200 400 Input Leakage Current (Notes 2, 3) I/O ports (Except PORTA) 1.0 PORTA 0.5 RA4/T0CKI 1.0 OSC1, MCLR 5.0 Unit Conditions V VDD = 4.5V to 5.5V otherwise V V Note1 V V V VDD = 4.5V to 5.5V otherwise V V Note1 A VDD = 5.0V, VPIN = VSS A A A A VSS VPIN VDD, pin at hi-impedance Vss VPIN VDD, pin at hi-impedance Vss VPIN VDD Vss VPIN VDD, XT, HS and LP osc configuration V V V V IOL=8.5 mA, VDD=4.5V, IOL=7.0 mA, VDD=4.5V, IOL=1.6 mA, VDD=4.5V, IOL=1.2 mA, VDD=4.5V, VOL Output Low Voltage D080 I/O ports D083 OSC2/CLKOUT (RC only) Output High Voltage (Note 3) I/O ports (Except RA4) VDD-0.7 VDD-0.7 VOH D090 D092 OSC2/CLKOUT - VDD-0.7 VDD-0.7 - 0.6 0.6 0.6 0.6 - - - - (RC only) * VOD Open-Drain High Voltage -40 to +85C +125C -40 to +85C +125C V IOH=-3.0 mA, VDD=4.5V, -40 to +85C V IOH=-2.5 mA, VDD=4.5V, +125C V IOH=-1.3 mA, VDD=4.5V, -40 to +85C V IOH=-1.0 mA, VDD=4.5V, +125C V RA4 pin 10* These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: In RC oscillator configuration, the OSC1 pin is a Schmitt Trigger input. It is not recommended that the PIC16C55X be driven with external clock in RC mode. 2: The leakage current on the MCLR pin is strongly dependent on applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as coming out of the pin. * 1998 Microchip Technology Inc. Preliminary DS40143C-page 73 PIC16C55X 10.3 DC CHARACTERISTICS: PIC16C55X (Commercial, Industrial, Extended) PIC16LC55X (Commercial, Industrial, Extended) (Cont.) Standard Operating Conditions (unless otherwise stated) Operating temperature -40C TA +85C for industrial and 0C TA +70C for commercial and -40C TA +125C for automotive Operating voltage VDD range as described in DC spec Table 10-1 Characteristic Param. Sym No. D100 COSC2 D101 Cio Capacitive Loading Specs on Output Pins OSC2 pin Min Typ Max 15 Unit Conditions pF In XT, HS and LP modes when external clock used to drive OSC1. pF All I/O pins/OSC2 (in RC 50 mode) * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: In RC oscillator configuration, the OSC1 pin is a Schmitt Trigger input. It is not recommended that the PIC16C55X be driven with external clock in RC mode. 2: The leakage current on the MCLR pin is strongly dependent on applied voltage level. The specified levels represent normal operating conditions. Higher leakage current may be measured at different input voltages. 3: Negative current is defined as coming out of the pin. DS40143C-page 74 Preliminary 1998 Microchip Technology Inc. PIC16C55X 10.4 Timing Parameter Symbology The timing parameter symbols have been created with one of the following formats: 1. TppS2ppS 2. TppS T F Frequency Lowercase subscripts (pp) and their meanings: pp ck CLKOUT io I/O port mc MCLR Uppercase letters and their meanings: S F Fall H High I Invalid (Hi-impedance) L Low T Time os t0 OSC1 T0CKI P R V Z Period Rise Valid Hi-Impedance FIGURE 10-1: LOAD CONDITIONS Load condition 2 Load condition 1 VDD/2 RL CL Pin CL Pin VSS VSS RL = 464 CL = 50 pF 15 pF 1998 Microchip Technology Inc. for all pins except OSC2 for OSC2 output Preliminary DS40143C-page 75 PIC16C55X 10.5 Timing Diagrams and Specifications FIGURE 10-2: EXTERNAL CLOCK TIMING Q4 Q1 Q3 Q2 Q4 Q1 OSC1 1 3 3 4 4 2 CLKOUT TABLE 10-2: Parameter No. EXTERNAL CLOCK TIMING REQUIREMENTS Sym Characteristic Min Typ Max Fos External CLKIN Frequency (Note 1) DC DC DC DC 0.1 1 DC 250 50 5 250 250 50 5 1.0 -- -- -- -- -- -- - -- -- -- -- -- -- -- Fos/4 4 20 200 4 4 20 200 -- -- -- -- 10,000 1,000 -- DC MHz MHz kHz MHz MHz MHz kHz ns ns s ns ns ns s s 100* 2* 20* 25* 50* 15* -- -- -- -- -- -- -- -- -- -- -- -- ns s ns ns ns ns Oscillator Frequency (Note 1) 1 Tosc External CLKIN Period (Note 1) Oscillator Period (Note 1) 2 TCY Instruction Cycle Time (Note 1) 3* TosL, TosH External Clock in (OSC1) High or Low Time 4* TosR, TosF External Clock in (OSC1) Rise or Fall Time Units Conditions XT and RC osc mode, VDD=5.0V HS osc mode LP osc mode RC osc mode, VDD=5.0V XT osc mode HS osc mode LP osc mode XT and RC osc mode HS osc mode LP osc mode RC osc mode XT osc mode HS osc mode LP osc mode TCY=FOS/4 XT osc mode LP osc mode HS osc mode XT osc mode LP osc mode HS osc mode * These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: Instruction cycle period (TCY) equals four times the input oscillator time-base period. All specified values are based on characterization data for that particular oscillator type under standard operating conditions with the device executing code. Exceeding these specified limits may result in an unstable oscillator operation and/or higher than expected current consumption. All devices are tested to operate at "min." values with an external clock applied to the OSC1 pin. When an external clock input is used, the "Max." cycle time limit is "DC" (no clock) for all devices. DS40143C-page 76 Preliminary 1998 Microchip Technology Inc. PIC16C55X FIGURE 10-3: CLKOUT AND I/O TIMING Q1 Q4 Q2 Q3 OSC1 11 10 22 23 CLKOUT 13 19 14 12 18 16 I/O Pin (input) 15 17 I/O Pin (output) new value old value 20, 21 Note: All tests must be do with specified capacitance loads (Figure 10-1) 50 pF on I/O pins and CLKOUT TABLE 10-3: Parameter # CLKOUT AND I/O TIMING REQUIREMENTS Sym Characteristic Min Typ Max Units 10* TosH2ckL OSC1 to CLKOUT (Note1) -- -- 75 -- 200 400 ns ns 11* TosH2ckH OSC1 to CLKOUT (Note1) -- -- 75 -- 200 400 ns ns 12* TckR CLKOUT rise time (Note1) -- -- 35 -- 100 200 ns ns 13* TckF CLKOUT fall time (Note1) -- -- 35 -- 100 200 ns ns 14* TckL2ioV CLKOUT to Port out valid (Note1) -- -- 20 ns 15* TioV2ckH Port in valid before CLKOUT (Note1) Tosc +200 ns Tosc +400 ns -- -- -- -- ns ns 16* TckH2ioI Port in hold after CLKOUT (Note1) 0 -- -- ns 17* TosH2ioV OSC1 (Q1 cycle) to Port out valid -- -- 50 150 300 ns ns 18* TosH2ioI OSC1 (Q2 cycle) to Port input invalid (I/O in hold time) 100 200 -- -- -- -- ns ns 19* TioV2osH Port input valid to OSC1 (I/O in setup time) 0 -- -- ns 20* TioR Port output rise time -- -- 10 -- 40 80 ns ns 21* TioF Port output fall time -- -- 10 -- 40 80 ns ns 22* Tinp RB0/INT pin high or low time 25 40 -- -- -- -- ns ns 23 Trbp RB<7:4> change interrupt high or low time Tcy -- -- ns * These parameters are characterized but not tested Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. Note 1: Measurements are taken in RC Mode where CLKOUT output is 4 x TOSC 1998 Microchip Technology Inc. Preliminary DS40143C-page 77 PIC16C55X FIGURE 10-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER TIMING VDD MCLR 30 Internal POR 33 PWRT Timeout 32 OSC Timeout Internal RESET Watchdog Timer RESET 31 34 34 I/O Pins TABLE 10-4: RESET, WATCHDOG TIMER, OSCILLATOR START-UP TIMER AND POWER-UP TIMER REQUIREMENTS Parameter No. Sym Characteristic Min 30 31 TmcL MCLR Pulse Width (low) 2000 -- -- ns -40 to +85C Twdt Watchdog Timer Time-out Period (No Prescaler) 7* 18 33* ms VDD = 5.0V, -40 to +85C 32 Tost Oscillation Start-up Timer Period -- 1024 TOSC -- -- TOSC = OSC1 period 33 Tpwrt Power-up Timer Period 28* 72 132* ms VDD = 5.0V, -40 to +85C TIOZ I/O hi-impedance from MCLR low -- 2.0 s 34 * Typ Max Units Conditions These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. DS40143C-page 78 Preliminary 1998 Microchip Technology Inc. PIC16C55X FIGURE 10-5: TIMER0 CLOCK TIMING RA4/T0CKI 41 40 42 TMR0 TABLE 10-5: Parameter No. 40 TIMER0 CLOCK REQUIREMENTS Sym Characteristic Min Tt0H T0CKI High Pulse Width No Prescaler Tt0L T0CKI Low Pulse Width No Prescaler * Tt0P T0CKI Period Units Conditions -- -- ns 10* -- -- ns 0.5 TCY + 20* -- -- ns 10* -- -- ns TCY + 40* N -- -- ns With Prescaler 42 Max 0.5 TCY + 20* With Prescaler 41 Typ N = prescale value (1, 2, 4, ..., 256) These parameters are characterized but not tested. Data in "Typ" column is at 5.0V, 25C unless otherwise stated. These parameters are for design guidance only and are not tested. FIGURE 10-6: LOAD CONDITIONS Load condition 2 Load condition 1 VDD/2 RL CL Pin CL Pin VSS VSS RL = 464 CL = 50 pF 15 pF 1998 Microchip Technology Inc. for all pins except OSC2 for OSC2 output Preliminary DS40143C-page 79 PIC16C55X NOTES: DS40143C-page 80 Preliminary 1998 Microchip Technology Inc. PIC16C55X 11.0 PACKAGING INFORMATION 11.1 Package Marking Information 18-Lead PDIP Example XXXXXXXXXXXXXXXXX XXXXXXXXXXXXXXXXX AABBCDE 18-Lead SOIC (.300") XXXXXXXXXXXX XXXXXXXXXXXX XXXXXXXXXXXX AABBCDE 18-Lead CERDIP Windowed PIC16C558 -04I / P456 9823 CBA Example PIC16C558 -04I / S0218 9818 CDK Example XXXXXXXX XXXXXXXX AABBCDE 20-Lead SSOP Example XXXXXXXXXXX XXXXXXXXXXX AABBCDE Legend: MM...M XX...X AA BB C D E Note: 16C558 /JW 9801 CBA PIC16C558 -04I / 218 9851 CBP Microchip part number information Customer specific information* Year code (last 2 digits of calendar year) Week code (week of January 1 is week `01') Facility code of the plant at which wafer is manufactured O = Outside Vendor C = 5" Line S = 6" Line H = 8" Line Mask revision number Assembly code of the plant or country of origin in which part was assembled In the event the full Microchip part number cannot be marked on one line, it will be carried over to the next line thus limiting the number of available characters for customer specific information. 1998 Microchip Technology Inc. Preliminary DS40143C-page 81 PIC16C55X Package Type: K04-010 18-Lead Ceramic Dual In-line with Window (JW) - 300 mil E D W2 2 n 1 W1 E1 A R A1 L c A2 eB B1 p B Units Dimension Limits PCB Row Spacing Number of Pins Pitch Lower Lead Width Upper Lead Width Shoulder Radius Lead Thickness Top to Seating Plane Top of Lead to Seating Plane Base to Seating Plane Tip to Seating Plane Package Length Package Width Radius to Radius Width Overall Row Spacing Window Width Window Length MIN n p B B1 R c A A1 A2 L D E E1 eB W1 W2 0.098 0.016 0.050 0.010 0.008 0.175 0.091 0.015 0.125 0.880 0.285 0.255 0.345 0.130 0.190 INCHES* NOM 0.300 18 0.100 0.019 0.055 0.013 0.010 0.183 0.111 0.023 0.138 0.900 0.298 0.270 0.385 0.140 0.200 MAX 0.102 0.021 0.060 0.015 0.012 0.190 0.131 0.030 0.150 0.920 0.310 0.285 0.425 0.150 0.210 MILLIMETERS MAX NOM 7.62 18 2.59 2.49 2.54 0.53 0.41 0.47 1.52 1.27 1.40 0.38 0.25 0.32 0.30 0.20 0.25 4.83 4.64 4.45 3.33 2.82 2.31 0.76 0.00 0.57 3.18 3.49 3.81 22.35 22.86 23.37 7.87 7.24 7.56 7.24 6.48 6.86 9.78 10.80 8.76 0.15 0.14 0.13 0.2 0.21 0.19 MIN * Controlling Parameter. JEDEC equivalent: MO-036 AE DS40143C-page 82 Preliminary 1998 Microchip Technology Inc. PIC16C55X Package Type: K04-007 18-Lead Plastic Dual In-line (P) - 300 mil E D 2 n 1 E1 A1 A R L c A2 B1 p B eB Units Dimension Limits PCB Row Spacing Number of Pins Pitch Lower Lead Width Upper Lead Width Shoulder Radius Lead Thickness Top to Seating Plane Top of Lead to Seating Plane Base to Seating Plane Tip to Seating Plane Package Length Molded Package Width Radius to Radius Width Overall Row Spacing Mold Draft Angle Top Mold Draft Angle Bottom INCHES* NOM 0.300 18 0.100 0.013 0.018 0.055 0.060 0.000 0.005 0.005 0.010 0.110 0.155 0.075 0.095 0.000 0.020 0.125 0.130 0.890 0.895 0.245 0.255 0.230 0.250 0.310 0.349 5 10 5 10 MIN n p B B1 R c A A1 A2 L D E E1 eB MAX 0.023 0.065 0.010 0.015 0.155 0.115 0.020 0.135 0.900 0.265 0.270 0.387 15 15 MILLIMETERS NOM MAX 7.62 18 2.54 0.33 0.46 0.58 1.40 1.52 1.65 0.00 0.13 0.25 0.13 0.25 0.38 2.79 3.94 3.94 1.91 2.41 2.92 0.00 0.51 0.51 3.18 3.30 3.43 22.61 22.73 22.86 6.22 6.48 6.73 5.84 6.35 6.86 7.87 8.85 9.83 5 10 15 5 10 15 MIN * Controlling Parameter. Dimension "B1" does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003" (0.076 mm) per side or 0.006" (0.152 mm) more than dimension "B1." Dimensions "D" and "E" do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010" (0.254 mm) per side or 0.020" (0.508 mm) more than dimensions "D" or "E." JEDEC equivalent: MS-001 AC 1998 Microchip Technology Inc. Preliminary DS40143C-page 83 PIC16C55X Package Type: K04-051 18-Lead Plastic Small Outline (SO) - Wide, 300 mil E1 p E D 2 B 1 n X 45 L R2 c A R1 Units Dimension Limits Pitch Number of Pins Overall Pack. Height Shoulder Height Standoff Molded Package Length Molded Package Width Outside Dimension Chamfer Distance Shoulder Radius Gull Wing Radius Foot Length Foot Angle Radius Centerline Lead Thickness Lower Lead Width Mold Draft Angle Top Mold Draft Angle Bottom L1 A2 INCHES* NOM 0.050 18 0.093 0.099 0.048 0.058 0.004 0.008 0.450 0.456 0.292 0.296 0.394 0.407 0.010 0.020 0.005 0.005 0.005 0.005 0.016 0.011 0 4 0.015 0.010 0.011 0.009 0.017 0.014 0 12 0 12 MIN p n A A1 A2 D E E1 X R1 R2 L L1 c B A1 MAX 0.104 0.068 0.011 0.462 0.299 0.419 0.029 0.010 0.010 0.021 8 0.020 0.012 0.019 15 15 MILLIMETERS NOM MAX 1.27 18 2.64 2.36 2.50 1.73 1.22 1.47 0.28 0.10 0.19 11.73 11.43 11.58 7.59 7.42 7.51 10.64 10.01 10.33 0.74 0.25 0.50 0.25 0.13 0.13 0.25 0.13 0.13 0.53 0.28 0.41 4 8 0 0.51 0.25 0.38 0.30 0.23 0.27 0.48 0.36 0.42 0 12 15 0 12 15 MIN * Controlling Parameter. Dimension "B" does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003" (0.076 mm) per side or 0.006" (0.152 mm) more than dimension "B." Dimensions "D" and "E" do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010" (0.254 mm) per side or 0.020" (0.508 mm) more than dimensions "D" or "E." JEDEC equivalent: MS-013 AB DS40143C-page 84 Preliminary 1998 Microchip Technology Inc. PIC16C55X Package Type: K04-072 20-Lead Plastic Shrink Small Outine (SS) - 5.30 mm E1 E p D B 2 1 n L R2 c A A1 R1 L1 A2 Units Dimension Limits Pitch Number of Pins Overall Pack. Height Shoulder Height Standoff Molded Package Length Molded Package Width Outside Dimension Shoulder Radius Gull Wing Radius Foot Length Foot Angle Radius Centerline Lead Thickness Lower Lead Width Mold Draft Angle Top Mold Draft Angle Bottom INCHES NOM 0.026 20 0.068 0.073 0.026 0.036 0.002 0.005 0.278 0.283 0.205 0.208 0.301 0.306 0.005 0.005 0.005 0.005 0.015 0.020 4 0 0.000 0.005 0.005 0.007 0.010 0.012 0 5 0 5 MIN p n A A1 A2 D E E1 R1 R2 L L1 c B MAX 0.078 0.046 0.008 0.289 0.212 0.311 0.010 0.010 0.025 8 0.010 0.009 0.015 10 10 MILLIMETERS* NOM MAX 0.65 20 1.73 1.86 1.99 0.66 0.91 1.17 0.05 0.13 0.21 7.07 7.20 7.33 5.20 5.29 5.38 7.78 7.90 7.65 0.13 0.13 0.25 0.13 0.13 0.25 0.38 0.51 0.64 0 4 8 0.13 0.25 0.00 0.18 0.22 0.13 0.32 0.38 0.25 0 5 10 0 5 10 MIN * Controlling Parameter. Dimension "B" does not include dam-bar protrusions. Dam-bar protrusions shall not exceed 0.003" (0.076 mm) per side or 0.006" (0.152 mm) more than dimension "B." Dimensions "D" and "E" do not include mold flash or protrusions. Mold flash or protrusions shall not exceed 0.010" (0.254 mm) per side or 0.020" (0.508 mm) more than dimensions "D" or "E." JEDEC equivalent: MO-150 AE 1998 Microchip Technology Inc. Preliminary DS40143C-page 85 PIC16C55X NOTES: DS40143C-page 86 Preliminary 1998 Microchip Technology Inc. PIC16C55X APPENDIX A: ENHANCEMENTS APPENDIX B: COMPATIBILITY The following are the list of enhancements over the PIC16C5X microcontroller family: To convert code written for PIC16C5X to PIC16C55X, the user should take the following steps: 1. 1. 2. 3. 4. 5. 6. 7. 8. 9. 10. 11. 12. 13. 14. 15. 16. 17. 18. Instruction word length is increased to 14 bits. This allows larger page sizes both in program memory (4K now as opposed to 512 before) and register file (up to 128 bytes now versus 32 bytes before). A PC high latch register (PCLATH) is added to handle program memory paging. PA2, PA1, PA0 bits are removed from STATUS register. Data memory paging is slightly redefined. STATUS register is modified. Four new instructions have been added: RETURN, RETFIE, ADDLW, and SUBLW. Two instructions TRIS and OPTION are being phased out although they are kept for compatibility with PIC16C5X. OPTION and TRIS registers are made addressable. Interrupt capability is added. Interrupt vector is at 0004h. Stack size is increased to 8 deep. Reset vector is changed to 0000h. Reset of all registers is revised. Three different reset (and wake-up) types are recognized. Registers are reset differently. Wake up from SLEEP through interrupt is added. Two separate timers, Oscillator Start-up Timer (OST) and Power-up Timer (PWRT) are included for more reliable power-up. These timers are invoked selectively to avoid unnecessary delays on power-up and wake-up. PORTB has weak pull-ups and interrupt on change feature. Timer0 clock input, T0CKI pin is also a port pin (RA4/T0CKI) and has a TRIS bit. FSR is made a full 8-bit register. "In-circuit programming" is made possible. The user can program PIC16C55X devices using only five pins: VDD, VSS, VPP, RB6 (clock) and RB7 (data in/out). PCON status register is added with a Power-on-Reset (POR) status bit. Code protection scheme is enhanced such that portions of the program memory can be protected, while the remainder is unprotected. PORTA inputs are now Schmitt Trigger inputs. 1998 Microchip Technology Inc. 2. 3. 4. 5. Preliminary Remove any program memory page select operations (PA2, PA1, PA0 bits) for CALL, GOTO. Revisit any computed jump operations (write to PC or add to PC, etc.) to make sure page bits are set properly under the new scheme. Eliminate any data memory page switching. Redefine data variables to reallocate them. Verify all writes to STATUS, OPTION, and FSR registers since these have changed. Change reset vector to 0000h. DS40143C-page 87 PIC16C55X NOTES: DS40143C-page 88 Preliminary 1998 Microchip Technology Inc. PIC16C55X INDEX A ADDLW Instruction ............................................................. 53 ADDWF Instruction ............................................................. 53 ANDLW Instruction ............................................................. 53 ANDWF Instruction ............................................................. 53 Architectural Overview .......................................................... 9 Assembler MPASM Assembler..................................................... 65 B BCF Instruction ................................................................... 54 Block Diagram TIMER0....................................................................... 29 TMR0/WDT PRESCALER .......................................... 32 BSF Instruction ................................................................... 54 BTFSC Instruction............................................................... 54 BTFSS Instruction............................................................... 55 C CALL Instruction ................................................................. 55 Clocking Scheme/Instruction Cycle .................................... 12 CLRF Instruction ................................................................. 55 CLRW Instruction................................................................ 55 CLRWDT Instruction ........................................................... 56 Code Protection .................................................................. 50 COMF Instruction................................................................ 56 Configuration Bits................................................................ 36 D Data Memory Organization ................................................. 13 DECF Instruction................................................................. 56 DECFSZ Instruction ............................................................ 56 Development Support ......................................................... 63 Development Tools ............................................................. 63 CLRWDT .................................................................... 56 COMF ......................................................................... 56 DECF.......................................................................... 56 DECFSZ ..................................................................... 56 GOTO ......................................................................... 57 INCF ........................................................................... 57 INCFSZ....................................................................... 57 IORLW........................................................................ 57 IORWF........................................................................ 58 MOVF ......................................................................... 58 MOVLW ...................................................................... 58 MOVWF...................................................................... 58 NOP............................................................................ 59 OPTION...................................................................... 59 RETFIE....................................................................... 59 RETLW ....................................................................... 59 RETURN..................................................................... 60 RLF............................................................................. 60 RRF ............................................................................ 60 SLEEP ........................................................................ 60 SUBLW....................................................................... 61 SUBWF....................................................................... 61 SWAPF....................................................................... 62 TRIS ........................................................................... 62 XORLW ...................................................................... 62 XORWF ...................................................................... 62 Instruction Set Summary .................................................... 51 INT Interrupt ....................................................................... 46 INTCON Register ............................................................... 18 Interrupts ............................................................................ 45 IORLW Instruction .............................................................. 57 IORWF Instruction .............................................................. 58 K KeeLoq Evaluation and Programming Tools ................... 66 E M Errata .................................................................................... 3 External Crystal Oscillator Circuit ....................................... 38 Fuzzy Logic Dev. System (fuzzyTECH-MP) .................... 65 MOVF Instruction................................................................ 58 MOVLW Instruction ............................................................ 58 MOVWF Instruction ............................................................ 58 MPLAB Integrated Development Environment Software.... 65 G N General purpose Register File ............................................ 13 GOTO Instruction................................................................ 57 NOP Instruction .................................................................. 59 I One-Time-Programmable (OTP) Devices .............................7 OPTION Instruction ............................................................ 59 OPTION Register ............................................................... 17 Oscillator Configurations .................................................... 37 Oscillator Start-up Timer (OST) .......................................... 40 F I/O Ports.............................................................................. 23 I/O Programming Considerations........................................ 27 ICEPIC Low-Cost PIC16CXXX In-Circuit Emulator ............ 63 ID Locations ........................................................................ 50 INCF Instruction .................................................................. 57 INCFSZ Instruction ............................................................. 57 In-Circuit Serial Programming............................................. 50 Indirect Addressing, INDF and FSR Registers ................... 21 Instruction Flow/Pipelining .................................................. 12 Instruction Set ADDLW ....................................................................... 53 ADDWF....................................................................... 53 ANDLW ....................................................................... 53 ANDWF....................................................................... 53 BCF............................................................................. 54 BSF ............................................................................. 54 BTFSC ........................................................................ 54 BTFSS ........................................................................ 55 CALL ........................................................................... 55 CLRF........................................................................... 55 CLRW ......................................................................... 55 1998 Microchip Technology Inc. O P Package Marking Information ............................................. 81 Packaging Information ........................................................ 81 PCL and PCLATH .............................................................. 20 PCON Register ................................................................... 19 PICDEM-1 Low-Cost PICmicro Demo Board ..................... 64 PICDEM-2 Low-Cost PIC16CXX Demo Board................... 64 PICDEM-3 Low-Cost PIC16CXXX Demo Board ................ 64 PICSTART Plus Entry Level Development System......... 63 Pinout Description .............................................................. 11 Port RB Interrupt................................................................. 46 PORTA ............................................................................... 23 PORTB ............................................................................... 25 Power Control/Status Register (PCON) ............................. 41 Power-Down Mode (SLEEP) .............................................. 49 Power-On Reset (POR) ...................................................... 40 Power-up Timer (PWRT) .................................................... 40 Preliminary DS40143C-page 89 PIC16C55X Prescaler ............................................................................. 32 PRO MATE II Universal Programmer............................... 63 Program Memory Organization ........................................... 13 Q Quick-Turnaround-Production (QTP) Devices ...................... 7 R RC Oscillator ....................................................................... 38 Reset................................................................................... 39 RETFIE Instruction.............................................................. 59 RETLW Instruction .............................................................. 59 RETURN Instruction............................................................ 60 RLF Instruction.................................................................... 60 RRF Instruction ................................................................... 60 S SEEVAL Evaluation and Programming System ............... 65 Serialized Quick-Turnaround-Production (SQTP) Devices ... 7 SLEEP Instruction ............................................................... 60 Software Simulator (MPLAB-SIM)....................................... 65 Special Features of the CPU............................................... 35 Special Function Registers ................................................. 15 Stack ................................................................................... 20 Status Register.................................................................... 16 SUBLW Instruction.............................................................. 61 SUBWF Instruction.............................................................. 61 SWAPF Instruction.............................................................. 62 T Timer0 TIMER0....................................................................... 29 TIMER0 (TMR0) Interrupt ........................................... 29 TIMER0 (TMR0) Module............................................. 29 TMR0 with External Clock........................................... 31 Timer1 Switching Prescaler Assignment................................. 33 Timing Diagrams and Specifications................................... 76 TMR0 Interrupt .................................................................... 46 TRIS Instruction .................................................................. 62 TRISA.................................................................................. 23 TRISB.................................................................................. 25 W Watchdog Timer (WDT) ...................................................... 47 WWW, On-Line Support........................................................ 3 X XORLW Instruction ............................................................. 62 XORWF Instruction ............................................................. 62 DS40143C-page 90 Preliminary 1998 Microchip Technology Inc. PIC16C55X ON-LINE SUPPORT Microchip provides on-line support on the Microchip World Wide Web (WWW) site. The web site is used by Microchip as a means to make files and information easily available to customers. To view the site, the user must have access to the Internet and a web browser, such as Netscape or Microsoft Explorer. Files are also available for FTP download from our FTP site. Connecting to the Microchip Internet Web Site Systems Information and Upgrade Hot Line The Systems Information and Upgrade Line provides system users a listing of the latest versions of all of Microchip's development systems software products. Plus, this line provides information on how customers can receive any currently available upgrade kits.The Hot Line Numbers are: 1-800-755-2345 for U.S. and most of Canada, and 1-602-786-7302 for the rest of the world. 981103 The Microchip web site is available by using your favorite Internet browser to attach to: www.microchip.com The file transfer site is available by using an FTP service to connect to: ftp://ftp.microchip.com The web site and file transfer site provide a variety of services. Users may download files for the latest Development Tools, Data Sheets, Application Notes, User's Guides, Articles and Sample Programs. A variety of Microchip specific business information is also available, including listings of Microchip sales offices, distributors and factory representatives. Other data available for consideration is: * Latest Microchip Press Releases * Technical Support Section with Frequently Asked Questions * Design Tips * Device Errata * Job Postings * Microchip Consultant Program Member Listing * Links to other useful web sites related to Microchip Products * Conferences for products, Development Systems, technical information and more * Listing of seminars and events 1998 Microchip Technology Inc. Trademarks: The Microchip name, logo, PIC, PICmicro, PICSTART, PICMASTER and PRO MATE are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. FlexROM, MPLAB and fuzzyLAB are trademarks and SQTP is a service mark of Microchip in the U.S.A. All other trademarks mentioned herein are the property of their respective companies. DS40143C-page 91 PIC16C55X READER RESPONSE It is our intention to provide you with the best documentation possible to ensure successful use of your Microchip product. If you wish to provide your comments on organization, clarity, subject matter, and ways in which our documentation can better serve you, please FAX your comments to the Technical Publications Manager at (602) 786-7578. Please list the following information, and use this outline to provide us with your comments about this Data Sheet. To: Technical Publications Manager RE: Reader Response Total Pages Sent From: Name Company Address City / State / ZIP / Country Telephone: (_______) _________ - _________ FAX: (______) _________ - _________ Application (optional): Would you like a reply? Device: PIC16C55X Y N Literature Number: DS40143C Questions: 1. What are the best features of this document? 2. How does this document meet your hardware and software development needs? 3. Do you find the organization of this data sheet easy to follow? If not, why? 4. What additions to the data sheet do you think would enhance the structure and subject? 5. What deletions from the data sheet could be made without affecting the overall usefulness? 6. Is there any incorrect or misleading information (what and where)? 7. How would you improve this document? 8. How would you improve our software, systems, and silicon products? DS40143C-page 92 1998 Microchip Technology Inc. PIC16C55X PIC16C55X Product Identification System To order or to obtain information, e.g., on pricing or delivery, please use the listed part numbers, and refer to the factory or the listed sales offices. PART NO. -XX X /XX XXX Pattern: 3-Digit Pattern Code for QTP (blank otherwise) Package: P SO SS JW* = = = = PDIP SOIC (Gull Wing, 300 mil body) SSOP (209 mil) Examples: Windowed CERDIP Temperature Range: I E = = = 0C to +70C -40C to +85C -40C to +125C Frequency Range: 04 04 20 = = = 200kHz (LP osc) 4 MHz (XT and RC osc) 20 MHz (HS osc) Device: PIC16C55X :VDD range 3.0V to 5.5V PIC16C55XT:VDD range 3.0V to 5.5V (Tape and Reel) PIC16LC55X:VDD range 2.5V to 5.5V PIC16LC55XT:VDD range 2.5V to 5.5V (Tape and Reel) f) PIC16C554 - 04/P 301 = Commercial temp., PDIP package, 4 MHz, normal VDD limits, QTP pattern #301. g) PIC16LC558- 04I/SO = Industrial temp., SOIC package, 200kHz, extended VDD limits. * JW Devices are UV erasable and can be programmed to any device configuration. JW Devices meet the electrical requirement of each oscillator type (including LC devices). Sales and Support Products supported by a preliminary Data Sheet may possibly have an errata sheet describing minor operational differences and recommended workarounds. To determine if an errata sheet exists for a particular device, please contact one of the following: 1. Your local Microchip sales office (see below) .2. The Microchip Corporate Literature Center U.S. FAX: (602) 786-7277 Please specify which device, revision of silicon and Data Sheet (include Literature #) you are using. For latest version information and upgrade kits for Microchip Development Tools, please call 1-800-755-2345 or 1-602-786-7302. 1998 Microchip Technology Inc. Preliminary DS40143C-page 93 PIC16C55X NOTES: DS40143C-page 94 Preliminary 1998 Microchip Technology Inc. PIC16C55X NOTES: 1998 Microchip Technology Inc. Preliminary DS40143C-page 95 Note the following details of the code protection feature on PICmicro(R) MCUs. * * * * * * The PICmicro family meets the specifications contained in the Microchip Data Sheet. Microchip believes that its family of PICmicro microcontrollers is one of the most secure products of its kind on the market today, when used in the intended manner and under normal conditions. There are dishonest and possibly illegal methods used to breach the code protection feature. All of these methods, to our knowledge, require using the PICmicro microcontroller in a manner outside the operating specifications contained in the data sheet. The person doing so may be engaged in theft of intellectual property. Microchip is willing to work with the customer who is concerned about the integrity of their code. Neither Microchip nor any other semiconductor manufacturer can guarantee the security of their code. Code protection does not mean that we are guaranteeing the product as "unbreakable". Code protection is constantly evolving. We at Microchip are committed to continuously improving the code protection features of our product. If you have any further questions about this matter, please contact the local sales office nearest to you. Information contained in this publication regarding device applications and the like is intended through suggestion only and may be superseded by updates. It is your responsibility to ensure that your application meets with your specifications. No representation or warranty is given and no liability is assumed by Microchip Technology Incorporated with respect to the accuracy or use of such information, or infringement of patents or other intellectual property rights arising from such use or otherwise. Use of Microchip's products as critical components in life support systems is not authorized except with express written approval by Microchip. No licenses are conveyed, implicitly or otherwise, under any intellectual property rights. Trademarks The Microchip name and logo, the Microchip logo, FilterLab, KEELOQ, microID, MPLAB, PIC, PICmicro, PICMASTER, PICSTART, PRO MATE, SEEVAL and The Embedded Control Solutions Company are registered trademarks of Microchip Technology Incorporated in the U.S.A. and other countries. dsPIC, ECONOMONITOR, FanSense, FlexROM, fuzzyLAB, In-Circuit Serial Programming, ICSP, ICEPIC, microPort, Migratable Memory, MPASM, MPLIB, MPLINK, MPSIM, MXDEV, PICC, PICDEM, PICDEM.net, rfPIC, Select Mode and Total Endurance are trademarks of Microchip Technology Incorporated in the U.S.A. Serialized Quick Turn Programming (SQTP) is a service mark of Microchip Technology Incorporated in the U.S.A. All other trademarks mentioned herein are property of their respective companies. (c) 2002, Microchip Technology Incorporated, Printed in the U.S.A., All Rights Reserved. Printed on recycled paper. Microchip received QS-9000 quality system certification for its worldwide headquarters, design and wafer fabrication facilities in Chandler and Tempe, Arizona in July 1999. The Company's quality system processes and procedures are QS-9000 compliant for its PICmicro(R) 8-bit MCUs, KEELOQ(R) code hopping devices, Serial EEPROMs and microperipheral products. In addition, Microchip's quality system for the design and manufacture of development systems is ISO 9001 certified. 2002 Microchip Technology Inc. M WORLDWIDE SALES AND SERVICE AMERICAS ASIA/PACIFIC Japan Corporate Office Australia 2355 West Chandler Blvd. Chandler, AZ 85224-6199 Tel: 480-792-7200 Fax: 480-792-7277 Technical Support: 480-792-7627 Web Address: http://www.microchip.com Microchip Technology Australia Pty Ltd Suite 22, 41 Rawson Street Epping 2121, NSW Australia Tel: 61-2-9868-6733 Fax: 61-2-9868-6755 Microchip Technology Japan K.K. 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India Liaison Office Divyasree Chambers 1 Floor, Wing A (A3/A4) No. 11, O'Shaugnessey Road Bangalore, 560 025, India Tel: 91-80-2290061 Fax: 91-80-2290062 Korea Microchip Technology Korea 168-1, Youngbo Bldg. 3 Floor Samsung-Dong, Kangnam-Ku Seoul, Korea 135-882 Tel: 82-2-554-7200 Fax: 82-2-558-5934 Singapore Microchip Technology Singapore Pte Ltd. 200 Middle Road #07-02 Prime Centre Singapore, 188980 Tel: 65-334-8870 Fax: 65-334-8850 Taiwan Microchip Technology Taiwan 11F-3, No. 207 Tung Hua North Road Taipei, 105, Taiwan Tel: 886-2-2717-7175 Fax: 886-2-2545-0139 EUROPE Denmark Microchip Technology Nordic ApS Regus Business Centre Lautrup hoj 1-3 Ballerup DK-2750 Denmark Tel: 45 4420 9895 Fax: 45 4420 9910 France Microchip Technology SARL Parc d'Activite du Moulin de Massy 43 Rue du Saule Trapu Batiment A - ler Etage 91300 Massy, France Tel: 33-1-69-53-63-20 Fax: 33-1-69-30-90-79 Germany Microchip Technology GmbH Gustav-Heinemann Ring 125 D-81739 Munich, Germany Tel: 49-89-627-144 0 Fax: 49-89-627-144-44 Italy Microchip Technology SRL Centro Direzionale Colleoni Palazzo Taurus 1 V. Le Colleoni 1 20041 Agrate Brianza Milan, Italy Tel: 39-039-65791-1 Fax: 39-039-6899883 United Kingdom Arizona Microchip Technology Ltd. 505 Eskdale Road Winnersh Triangle Wokingham Berkshire, England RG41 5TU Tel: 44 118 921 5869 Fax: 44-118 921-5820 01/18/02 2002 Microchip Technology Inc.