DNT90C - RFM - Datasheet.Directory

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DNT90 Series

900 MHz Spread Spectrum

Wireless Transceivers

Integration Guide

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Important Regulatory Information

RFM Product FCC ID: HSW-DNT90

IC 4492A-DNT90

Note: This equipment has been tested and found to comply with the limits for a Class B digital

device, pursuant to Part 15 of the FCC Rules. These limits are designed to provide reasonable pro-

tection against harmful interference in a residential installation. This equipment generates, uses

and can radiate radio frequency energy and, if not installed and used in accordance with the in-

structions, may cause harmful interference to radio communications. If this equipment does

cause harmful interference to radio or television reception, which can be determined by turning

the equipment off and on, the user is encouraged to try to correct the interference by one or more

of the following measures:

1) Re-orientate or relocate the receiving antenna,

2) Increase the separation between the equipment and the radiator,

3) Connect the equipment to an outlet on a circuit different from that to which the receiver is connected,

4) Consult the dealer or an experienced radio/TV technician for help.

FCC Antenna Gain Restriction and MPE Statement:

The DNT90 has been designed to operate with any dipole antenna of up to 5.1 dBi of gain, any Yagi of up

to 6.1 dBi gain, or chip antenna JTI-0915AT43A0026.

The antenna(s) used for this transmitter must be installed to provide a separation distance of at least

20 cm from all persons and must not be co-located or operating in conjunction with any other antenna or

transmitter.

Industry Canada Specific Statements:

The term “IC:” before the radio certification number only signifies that Industry Canada technical specifica-

tions were met.

This Class B digital apparatus meets all requirements of the Canadian Interference Causing Equipment

Regulations. Operation is subject to the following two conditions: (1) this device may not cause harmful

interference, and (2) this device must accept any interference received, including interference that may

cause undesired operation.

Cet appareillage numérique de la classe B répond à toutes les exigences de l'interférence canadienne

causant des règlements d'équipement. L'opération est sujette aux deux conditions suivantes: (1) ce dis-

positif peut ne pas causer l'interférence nocive, et (2) ce dispositif doit accepter n'importe quelle interfé-

rence reçue, y compris l'interférence qui peut causer l'opération peu désirée.

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IC RSS-210 Detachable Antenna Gain Restriction:

This device has been designed to operate with the antennas listed below, and having a maximum gain of

6.1 dB. Antennas not included in this list or having a gain greater than 6.1 dB are strictly prohibited for

use with this device. The required antenna impedance is 50 ohms:

RFM RWA092R Omnidirectional Dipole Antenna, 2 dBi

RFM OMNI095 Omnidirectional Dipole Antenna, 5 dBi

RFM YAGI099 Directional Antenna, 6.1 dBi

Chip Antenna JTI-0915AT43A0026, -1 dBi

To reduce potential radio interference to other users, the antenna type and its gain should be so chosen

that the equivalent isotropically radiated power (e.i.r.p.) is not more than that permitted for successful

communication.

See Section 6.8 of this manual for regulatory notices and labeling requirements. Changes or modifica-

tions to a DNT90 not expressly approved by RFM may void the user’s authority to operate the module.

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Table of Contents

1.0 DNT90 Introduction .......................................................................................................................... 6

1.1 Why Spread Spectrum? ............................................................................................................ 6

1.2 Frequency Hopping versus Direct Sequence ............................................................................ 7

2.0 DNT90 System Overview ................................................................................................................. 8

2.1 Point-to-Point Systems .............................................................................................................. 8

2.2 Point-to-Multipoint Systems ....................................................................................................... 9

2.3 Store-and-Forward Systems ...................................................................................................... 9

2.4 RF Channel Access ................................................................................................................. 10

2.5 DNT90 Addressing .................................................................................................................. 11

2.6 Network Linking and Slot Registration .................................................................................... 11

2.6.1 Fast Linking Techniques ................................................................................................... 12

2.7 Transparent and Protocol-formatted Serial Data ..................................................................... 12

3.0 DNT90 Application Interfaces ........................................................................................................ 13

3.1 Serial Ports .............................................................................................................................. 13

3.2 SPI Port ................................................................................................................................... 13

3.3 Digital I/O ................................................................................................................................. 16

3.4 Analog I/O ................................................................................................................................ 16

3.5 I/O Event Reporting and I/O Binding ....................................................................................... 17

4.0 DNT90 System Configuration ........................................................................................................ 18

4.1 Configuration Parameters ........................................................................................................ 18

4.2 Configuring a Basic Point-to-Point System ............................................................................. 18

4.3 Configuring a Basic Point-to-Multipoint System ...................................................................... 18

4.4 Configuring a Customized Point-to-Point or Point-to-Multipoint System ................................. 19

4.5 Configuring a Store-and-Forward System ............................................................................... 20

4.6 Slot Buffer Sizes, Number of Slots, Messages per Hop and Hop Duration ............................ 21

5.0 DNT90 Application Interface Configuration.................................................................................... 23

5.1 Configuring the Serial Port ...................................................................................................... 23

5.2 Configuring the SPI Port .......................................................................................................... 24

5.3 Configuring Digital I/O ............................................................................................................. 24

5.4 Configuring Analog I/O ............................................................................................................ 24

5.5 Configuring I/O Event Reporting and I/O Binding .................................................................... 25

5.6 Configuring Sleep Mode .......................................................................................................... 26

6.0 DNT90 Hardware ........................................................................................................................... 27

6.1 Electrical Specifications ........................................................................................................... 28

6.2 Module Pin Out ........................................................................................................................ 29

6.3 Antenna Connector .................................................................................................................. 30

6.4 Power Supply and Input Voltages ........................................................................................... 31

6.5 ESD and Transient Protection ................................................................................................. 31

6.6 Interfacing to 5 V Logic Systems ............................................................................................. 31

6.7 Mounting and Enclosures ........................................................................................................ 31

6.8 Labeling and Notices ............................................................................................................... 32

7.0 DNT90 Protocol-formatted Messages ............................................................................................ 33

7.1 Protocol Formats ..................................................................................................................... 33

7.2 Message Types ....................................................................................................................... 33

7.3 Message Format Details .......................................................................................................... 34

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7.4 Configuration Parameter Registers ......................................................................................... 41

7.4.1 Bank 0x00 - Transceiver Setup ......................................................................................... 41

7.4.2 Bank 0x01 - System Settings ............................................................................................ 44

7.4.3 Bank 0x02 - Status Parameters ........................................................................................ 45

7.4.4 Bank 0x03 - Serial and SPI Settings ................................................................................. 47

7.4.5 Bank 0x04 - Host Protocol Settings .................................................................................. 48

7.4.6 Bank 0x05 - I/O Parameters ............................................................................................. 49

7.4.7 Bank 0x06 - I/O Settings ................................................................................................... 50

7.4.8 Bank 0x0FF - Special Functions ....................................................................................... 55

7.5 Protocol-formatted Message Examples .................................................................................. 56

7.5. 1 Data Message ................................................................................................................... 56

7.5.2 Configuration Message ..................................................................................................... 57

7.5.3 Sensor Message ............................................................................................................... 57

7.5.4 Event Message ................................................................................................................. 58

8.0 DNT90DK/DNT90ADK Developer’s Kits ........................................................................................ 59

8.1 Kit Contents ............................................................................................................................. 59

8.2 Additional Items Needed ......................................................................................................... 59

8.3 Developer’s Kit Default Operating Configuration ..................................................................... 59

8.4 Developer’s Kit Hardware Assembly ....................................................................................... 60

8.5 DNT90 Utility Program ............................................................................................................. 61

8.6 Initial Kit Operation .................................................................................................................. 62

8.6.1 Serial Communication and Radio Configuration ............................................................... 65

8.7 DNT90 Interface Board Features ............................................................................................ 71

9.0 Troubleshooting ............................................................................................................................. 73

9.1 Diagnostic Port Commands ..................................................................................................... 73

10.0 Appendices .................................................................................................................................... 74

10.1 Ordering Information ................................................................................................................ 74

10.2 Technical Support .................................................................................................................... 74

10.3 DNT90/DNT90A Mechanical Specifications ............................................................................ 75

10.4 DNT90 Development Board Schematic .................................................................................. 79

11.0 Warranty ......................................................................................................................................... 82

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1.0 DNT90 Introduction

DNT90 transceivers provide highly-reliable wireless connectivity for point-to-point, point-to-multipoint and

store-and-forward radio applications. Frequency hopping spread spectrum (FHSS) technology ensures

maximum resistance to multipath fading and robustness in the presence of interfering signals, while oper-

ation in the 900 MHz ISM band allows license-free use in North America, South America and Australia.

The DNT90 supports serial data rates for host communications from 1.2 to 250 kbps, plus three SPI data

rates from 125 to 500 kbps. On-board data buffering plus an error-correcting radio protocol provide

smooth data flow and simplify the task of integration with existing applications. Key DNT90 features in-

clude:

 Multipath fading resistant frequency hopping

technology with up to 52 frequency chan-

nels, 902.76 to 927.24 MHz

 Receiver protected by low-loss SAW filter,

providing excellent receiver sensitivity and

interference rejection important in outdoor

applications

 Ad Hoc TDMA operating mode supports a

large number of remotes with low latency

for burst data streaming

 Simple interface handles both data and con-

trol at up to 250 kbps on the serial port or

500 kbps on the SPI port

 Support for point-to-point, point-to-multipoint,

peer-to-peer and store & forward networks

 AES encryption provides protection from

eavesdropping

 FCC 15.247 and IC RSS-210 certified for

license-free operation

 Nonvolatile memory stores DNT90 configura-

tion when powered off

 Five mile plus range with omnidirectional

antennas (antenna height dependent)

 Selectable +16 dBm (40 mW) or +22 dBm

(158 mW) transmit power levels

 Transparent ARQ protocol with data

buffering ensures data integrity

 Automatic I/O event reporting mode simplifies

application development

 Analog and Digital I/O supports wireless

sensing applications

 I/O binding mode provides wireless transmis-

sion of analog and digital values

1.1 Why Spread Spectrum?

A radio channel can be very hostile, corrupted by noise, path loss and interfering transmissions from oth-

er radios. Even in an interference-free environment, radio performance faces serious degradation from a

phenomenon known as multipath fading. Multipath fading results when two or more reflected rays of the

transmitted signal arrive at the receiving antenna with opposing phases, thereby partially or completely

canceling the signal. This problem is particularly prevalent in indoor installations. In the frequency do-

main, a multipath fade can be described as a frequency-selective notch that shifts in location and intensity

over time as reflections change due to motion of the radio or objects within its range. At any given time,

multipath fades will typically occupy 1% - 2% of the band. From a probabilistic viewpoint, a conventional

radio system faces a 1% - 2% chance of signal impairment at any given time due to multipath fading.

Spread spectrum reduces the vulnerability of a radio system to both multipath fading and jammers by dis-

tributing the transmitted signal over a larger region of the frequency band than would otherwise be neces-

sary to send the information. This allows the signal to be reconstructed even though part of it may be lost

or corrupted in transmission.

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Narrow-band versus spread spectrum transmission

Figure 1.1.1

1.2 Frequency Hopping versus Direct Sequence

The two primary approaches to spread spectrum are direct sequence spread spectrum (DSSS) and fre-

quency hopping spread spectrum (FHSS), either of which can generally be adapted to a given applica-

tion. Direct sequence spread spectrum is produced by multiplying the transmitted data stream by a much

faster, noise-like repeating pattern. The ratio by which this modulating pattern exceeds the bit rate of the

base-band data is called the processing gain, and is equal to the amount of rejection the system affords

against narrow-band interference from multipath and jammers. Transmitting the data signal as usual, but

varying the carrier frequency rapidly according to a pseudo-random pattern over a broad range of chan-

nels produces a frequency hopping spectrum system.

Forms of spread spectrum - direct sequence and frequency hopping

Figure 1.1.2

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One disadvantage of direct sequence systems is that due to design issues related to broadband transmit-

ters and receivers, they generally employ only a minimal amount of spreading, often no more than the

minimum required by the regulating agencies. For this reason, the ability of DSSS systems to overcome

fading and in-band jammers is relatively weak. By contrast, FHSS systems are capable of hopping

throughout the entire band, statistically reducing the chances that a transmission will be affected by fad-

ing or interference. This means that a FHSS system will degrade gracefully as the band gets noisier,

while a DSSS system may exhibit uneven coverage or work well until a certain point and then give out

completely.

Because it offers greater immunity to interfering signals, FHSS is often the preferred choice for co-located

systems. Since direct sequence signals are very wide, they can offer only a few non-overlapping chan-

nels, whereas multiple hoppers can interleave, minimizing interference. Frequency hopping systems do

carry some disadvantages, in that they require an initial acquisition period during which the receiver must

lock on to the moving carrier of the transmitter before any data can be sent, which typically takes several

seconds. In summary, frequency hopping systems generally feature greater coverage and channel utiliza-

tion than comparable direct sequence systems. Of course, other implementation factors such as size,

cost, power consumption and ease of implementation must also be considered before a final radio design

choice can be made.

2.0 DNT90 System Overview

A DNT90 radio can be configured to operate in one of three modes - base, remote or router. A base con-

trols a DNT90 system, and interfaces to an application host such as a PC or Internet gateway. A remote

functions to transmit or receive serial, digital (state) and analog data. A router alternates between func-

tioning as a remote on one hop and a network base on the next hop. When acting as a remote, the router

stores messages it receives from its parent, and then repeats the messages to its child radios when act-

ing as a network base. Likewise, a router will store messages received from its child radios when acting

as a base, and repeat them to its parent when acting as a remote. Any message addressed directly to a

router is processed by the router rather than being repeated.

2.1 Point-to-Point Systems

A DNT90 system contains at least one network. The simplest DNT90 topology is a point-to-point system,

as shown in Figure 2.1.1. This system consists of a base and one remote forming a single network. Point-

to-point systems are often used to replace wired serial connections. Point-to-point systems are also used

to transmit switch positions or analog signals from one location to another.

Figure 2.1.1

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2.2 Point-to-Multipoint Systems

Figure 2.2.1 shows the topology of a point-to-multipoint (star) system, which consists of a base and more

than one remote in a single network. Point-to-multipoint systems are typically used for data, sensor and

alarm systems. While most traffic in a point-to-multipoint system is between the base and the remotes,

DNT90 technology also allows for peer-to-peer communication from one remote to another.

Figure 2.2.1

2.3 Store-and-Forward Systems

Figure 2.3.1 shows the topology of a store-and-forward system, which consists of a base, one or more

routers, one or more remotes, and two or more networks. Networks in a store-and-forward system form

around the base and each router. The base and the routers are referred to as the parents of the networks

they form. The rest of the radios in each network are referred to as child radios. Note that a router is a

child of the base or another router while being the parent of its own network. Each network parent trans-

mits beacons to allow child radios to synchronize with its hopping pattern and join its network. Different

frequency hopping patterns are used by the parent radios in a system, minimizing interference between

networks.

Store-and-forward systems are used to cover larger areas than is possible with point-to-point or point to-

multipoint systems. The trade-off in store-and-forward systems is longer delivery times due to receiving

and retransmitting a message several times. Store-and-forward systems are especially useful in applica-

tions such as agriculture where data is only collected periodically.

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Figure 2.3.1

2.4 RF Channel Access

The time a DNT90 network stays on each frequency in its hopping pattern is called the hop duration or

dwell time, which can be configured from 8 to 100 ms. Radio communication during each dwell is orga-

nized as a time division multiple access (TDMA) frame. A DNT90 frame begins with a base-mode beacon,

followed by 1 to 8 time slots used by the network children to transmit to their parent, as shown in Figure

2.4.1. A base-mode beacon can include up to 8 messages addressed to one or more child radios. The

number of slots is chosen accommodate the number of children that need to send messages each hop.

S y s t e m / N e t w o r k

C o n t r o l

M e s s a g e s t o

N e t w o r k C h i l d r e n

B a s e - M o d e

B e a c o n

E x a m p l e D N T 9 0 C o m m u n i c a t i o n F r a m e

A s s i g n e d

S l o t

O p e n

S l o t

O p e n

S l o t

M e s s a g e s

f r o m C h i l d

Figure 2.4.1

Each beacon includes the status of all slots - either registered (assigned) or open. When a child radio has

information to transmit to its parent, it randomly selects one of the open slots and transmits all or the first

part of its data. If the parent successfully receives the transmission, it includes the child’s MAC address in

the next beacon. This signals the child radio that the slot is temporarily registered to it, allowing the child

to efficiently stream any remaining data to the base hop-by-hop until it is all sent.

If a child radio does not see its address in the next beacon following its transmission, it again randomly

selects an open slot and retransmits its data. During times when there are no open slots, a child radio

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keeps its data queued and continues to look for an open slot in each beacon until at least one slot be-

comes available. The access method the DNT90 uses is referred to as Ad Hoc TDMA.

2.5 DNT90 Addressing

Each DNT90 has a unique MAC address. The MAC address can be read or bar-code scanned from the

label on top of each radio. A DNT90 radio in any mode (base/router/remote) can be addressed using its

MAC address. A DNT90 base can be addressed using either its MAC address or address 0x000000. A

DNT90 can send a message to all other DNT90’s in its system by using the broadcast address

0xFFFFFF.

The base and all routers (parents) hold base-mode network IDs, which are transmitted in every beacon.

All routers and remotes hold parent network IDs and optionally alternate parent network IDs to compare

against the base-mode network IDs in the beacons they receive. A child router or remote is allowed to

join a parent if its parent network ID or alternate parent network ID matches the parent’s base-mode net-

work ID, or with any parent when its parent network ID is set to 0xFF (wildcard).

In a point-to-point or point-to-multipoint system, the default base-mode network ID of 0xFF (wildcard) can

be used. In a store-and-forward system, however, the base-mode network IDs of all routers must be set

to different values between 0x00 to 0x3F. If the base-mode network ID of 0x00 is assigned to a router, the

base must be assigned an unused base-mode network ID between 0x01 and 0x3F. Leaving all parent

network IDs in a store-and-forward system set to the default value of 0xFF allows networks to automati-

cally form, and self-repair if a parent router fails. Enabling the alternate parent network ID also provides

self-repairing message routing.

All DNT90 radios hold a system ID that can be used to distinguish systems that physically overlap. In a

DNT90 system, the system ID must be different from those used by overlapping systems to provide mes-

sage filtering. Also, using different base-mode network IDs for all networks in overlapping systems helps

reduce hopping pattern collisions.

The store-and-forward path between the base and any other radio in a system can be determined by

reading the radio’s ParentMacAddress parameter. If this address is not the base, then reading the

ParentMacAddress parameter of its parent, grandparent, etc., in succession reveals the complete path to

the base. Path determination is useful in optimizing and troubleshooting systems during commissioning

and maintenance.

2.6 Network Linking and Slot Registration

When first turned on, a DNT90 router or remote rapidly scans all frequency channels in its operating band

to acquire synchronization and link to a parent based on a system ID match plus a base-mode network ID

to parent network ID/alternate parent network ID match (or by using a wildcard (0xFF) parent network ID).

In addition to the slot status and the MAC addresses of child radios holding slot registrations, each base-

mode beacon includes one of a number of cycled control parameters. The cycled parameters are collect-

ed by child radios, allowing them to register with a parent, and to later follow any control parameter

changes. When a router or remote has collected a full set of cycled parameters, it can issue an optional

initial heartbeat message and then optional periodic heartbeat messages which allow an application to

maintain the status of all routers and remotes in its DNT90 system.

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When a router/remote has data to send to its parent, it picks an open slot at random and transmits. It then

looks for its MAC address in the next beacon. If its MAC address is present in the beacon, it is temporarily

registered to the slot and continues to use it until all current data is sent, or its MAC address drops off the

beacon.

2.6.1 Fast Linking Techniques

Minimizing linking time is important in certain applications. For example, when the remotes in a system

are battery powered and wake from sleep occasionally to report data. Minimizing linking time increases

the operating battery life of the remotes. The basic techniques to reduce linking time include:

- use no more hop duration (dwell time) than necessary

- use no more slots than necessary for the application

- use no larger base slot size (BSS) than necessary

- transmit only dynamic cycle parameters once system nodes have static parameters

Once a complete set of cycled parameters has been receive by all routers and remotes in a system and

stored in memory, it is not necessary to send all of them again during a re-linking, as long as the system

configuration remains stable.

As discussed in Section 7.4.1, the base station in a DNT90 system can be configured to transmit “fast

beacons” for a period of time when powered up, reset or triggered with the FastBeaconTrig parameter.

Fast beacons are sent using a very short hop dwell time, facilitating fast system linking.

2.7 Transparent and Protocol-formatted Serial Data

A DNT90 remote can directly input and output data bytes and data strings on its serial port. This is re-

ferred to as transparent serial port operation. In a point-to-point system, the base can also be configured

for transparent serial port operation.

In all other cases, serial data must be protocol formatted:

- configuration commands and replies

- I/O event messages

- announcement messages including heartbeats

Protocol-formatted messages are discussed in detail in Section 7. Briefly, protocol-formatted messages

include a start-of-messages character, message length and message type information, the destination

address of the message, and the message payload.

Transparent data is routed using a remote transparent destination address. In a remote, this address de-

faults to the base, 0x000000, and in the base this address defaults to broadcast, 0xFFFFFF. These de-

faults can be overridden with specific radio addresses. For example, it is possible to set up transparent

peer-to-peer routing between two remotes in a point-to-multipoint or store-and-forward system by loading

specific MAC addresses in each radio’s remote transparent destination address.

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3.0 DNT90 Application Interfaces

A DNT90 module provides a variety of application interfaces including two serial ports, an SPI port, six

digital I/O ports (logic state), three 12-bit ADC input ports, and two 12-bit DAC output ports. Each of these

interfaces is discussed below.

3.1 Serial Ports

The DNT90 includes two serial ports, one for communication and an optional one for diagnostics. The

communication port is a full-duplex UART interface with hardware flow control on two of the digital I/O

pins an optional feature. One digital I/O pin can also be configured as an RS485 enable function. The se-

rial communication port can be configured with baud rates from 1.2 to 250 kbps, with 9.6 kbps the default

baud rate. The DNT90 communication port transmits/receives 8-bit data with a choice of even, odd or no

parity and 1 or 2 stop bits. The default configuration is no parity and one stop bit. See Section 5.1 for rec-

ommendations on configuring the communication port, and Section 7.4.4 for detailed information on con-

figuration parameters. The diagnostic port is enabled as an alternate function on two digital I/O pins, and

can be configured with baud rates from 1.2 to 250 kbps, with 9.6 kbps the default baud rate. The diagnos-

tic port transmits/receives 8-bit data with no parity and 1 stop bit. See Section 7.4.8 for diagnostic port

configuration details.

3.2 SPI Port

The DNT90 serial peripheral interface (SPI) port can operate either as a master or a slave. The port

includes the four standard SPI connections - MISO, MOSI, SCLK and /SS, plus three signals used to

support SPI slave mode operation - /HOST_RTS, /HOST_CTS and DAV. The serial port and SPI master

mode can run simultaneously. Serial port operation is disabled when the SPI port is configured for slave

mode. Note that all SPI slave mode messages must be protocol formatted.

D N T 9 0P e r i p h e r a l

D N T 9 0 S P I M a s t e r M o d e S i g n a l i n g

/ S S

S C L K

M O S I

M I S O

Figure 3.2.1

The DNT90 SPI port can run at three clock rates in master mode - 125, 250 or 500 kbps. There are two

message sources available to a DNT90 SPI master, a protocol-formatted RxData message or a stored

command. The DNT90 master will clock a message from either source into its slave and return the bytes

clocked out as a protocol-formatted TxData message. The DNT90 event timer triggers sending the stored

command to the DNT90’s slave. The stored command can be up to 16 bytes in length. Figure 3.2.1

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shows the required SPI master mode-signal connections, and Figure 3.2.2 shows the SPI master-mode

timing.

/ S S

S C L K

M O S I

M I S O

S P I B i t C l o c k

C o m m a n d t o S l a v e

D a t a f r o m S l a v e

D N T 9 0 S P I M a s t e r M o d e O p e r a t i o n

Figure 3.2.2

In SPI slave mode, the host can stream data into DNT90 at up to 250 kbps, provided the host suspends

clocking within 10 bytes following a low-to-high transition on /HOST_CTS. The host can clock data into

the DNT90 at up to 4 Mbps for data bursts of up to 50 bytes, provided the interval from the end of one

burst to the start of the next burst is at least 2 ms, and the host suspends clocking on a low-to-high transi-

tion on /HOST_CTS. See Figure 3.2.4

D N T 9 0H o s t

D N T 9 0 S P I S l a v e M o d e S i g n a l i n g

/ S S

S C L K

M O S I

M I S O

/ H O S T _ C T S

DAV

/ H O S T _ R T S

Figure 3.2.3

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/ S S

/ H O S T _ C T S

S C L K

M O S I

S P I B i t C l o c k

M e s s a g e t o D N T 9 0

D N T 9 0 S P I S l a v e M o d e M e s s a g e L o a d

Figure 3.2.4

The host should use the following steps to fetch data from a DNT90 SPI slave, as show in Figure 3.2.5:

1. The host sets the /HOST_RTS signal high to allow the DNT90 to signal data available.

2. The DNT90 sets the data available (DAV) high to signal the host it has data.

3. The host set the /SS signal low to enable SPI operation.

4. The host clocks in one dummy byte (ignore the output byte) and then sets /HOST_RTS low.

5. The host begins to clock out the data, which can include several messages.

6. The host continues to clock out data until a 0x00 byte occurs in the byte stream where a 0xFB

start-of-message would be expected.

7. The host has now clocked out all messages and the 0x00 is discarded.

8. The host sets /HOST_RTS and /SS high to allow the DNT90 to signal DAV the next time it

has data.

Note that the DAV signal can go low before the last message is clocked out. It is not a reliable indication

that the last byte of the message(s) has been clocked out. See Section 5.2 for recommendations on con-

figuring the SPI port, and Section 7.4.4 for detailed information on SPI port configuration parameters.

/ S S

DAV

S C L K

M I S O

S P I C l o c k

P r o t o c o l F o r m a t t e d R X M e s s a g e

D N T 9 0 S P I S l a v e M o d e R X M e s s a g e R e t r i e v a l

L e n g t h B y t e

0 x F B S t a r t o f M e s s a g e

/ H O S T _ R T S

Figure 3.2.5

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3.3 Digital I/O

The DNT90’s six digital (state) I/O ports are labeled GPIO0 through GPIO5. GPIO5 has an alternate func-

tion of /HOST_ RTS and GPIO4 of /HOST_CTS, providing hardware handshaking for the serial port and

SPI slave mode operation. If serial port hardware handshaking is not required and SPI slave mode is not

enabled, GPIO4 and GPIO5 can be used for other digital I/O functions. When SPI slave mode is enabled,

GPIO5 and GPIO4 must be used for /HOST_RTS and /HOST_CTS respectively, and GPIO3 must be

used to provide the DAV signal (SPI slave mode overrides any other configuration for these ports). Ex-

cept in SPI slave mode, GPIO0 through GPIO5 are available for customer-defined functions:

- The direction of each GPIO pin can be set for both active and sleep modes.

- The initial state (power on) of all GPIO pins configured as outputs can be set.

- The state of all GPIO pins configured as outputs in sleep mode can be set.

- GPIO triggering of I/O event reporting can be configured.

- GPIO level control of sleep hold-off can be configured.

See Section 5.3 for recommendations on configuring the digital I/O, and Sections 7.4.6 and 7.4.7 for de-

tailed information on GPIO parameters.

3.4 Analog I/O

The DNT90’s three ADC input channels are labeled ADC0 through ADC2. The ADC can be disabled if

unused to reduce current consumption. The ADC can be operated in either single-ended mode or differ-

ential mode. In single-ended mode, up to three sensor inputs can be measured. The negative sensor in-

puts are connected to ground and the positive sensor inputs are connected to ADC0, ADC1 and ADC2

respectively. Single-ended measurements are unsigned 11-bit values. In differential mode, one or two

sensor inputs can be measured as 12-bit signed values. The first differential measurement is the differ-

ence between the voltage on ADC1 and the voltage on ADC0, and is referred to as the ADC0 differential

measurement. The second differential measurement is the difference between ADC2 and ADC0, and is

referred to as the ADC1 differential measurement. Operating the ADC in differential mode takes ad-

vantage of common mode rejection to provide the best measurement stability. Differential mode also in-

corporates a programmable gain preamplifier function, with gains settings from 1 to 64 available.

There are two options for the ADC full-scale reference:

1. The DNT90 regulated supply voltage divided by 1.6, or about 2.06 V

2. A low impedance voltage source applied to the DNT90’s ADC_EXT_REF input pin, 2.7 V maxi-

mum. If no connection is made to this pin, a voltage equal to about 2.7 V will be present.

Note that when differential ADC mode is used, the maximum output voltage available from the preamplifi-

er at any gain setting is 2.4 V, so the maximum ADC reading that can be made using a 2.7 V ADC refer-

ence will be about 88.9% of full scale. The ADC channels are read each ADC sample interval, which is

configurable. High and low measurement thresholds can be set for each ADC channel to trigger I/O event

reporting messages.

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The DNT90’s two DAC outputs are labeled DAC0 and DAC1. The DACs can be disabled if unused to re-

duce current consumption. The DAC settings have 12-bit resolution. There are two options for the DAC

full-scale reference:

1. The DNT90 regulated supply voltage, about 3.3 V

2. A low impedance voltage source applied to the DNT90’s ADC_EXT_REF input pin, 2.7 V maxi-

mum. If no connection is made to this pin, a voltage equal to about 2.7 V will be present.

See Section 5.4 for recommendations on configuring the analog I/O, and Sections 7.4.6 and 7.4.7 for de-

tailed information on analog I/O parameters.

3.5 I/O Event Reporting and I/O Binding

The DNT90’s I/O event reporting function can generate a protocol-formatted RxEvent message when

triggered by one of the following I/O events:

- A specific state change of GPIO0, GPIO1, GPIO2 or GPIO3.

- Firing of the periodic event report timer.

- A high or low threshold exceeded on a measurement by ADC0, ADC1 or ADC2.

An I/O report message includes:

- The states of GPIO0 through GPIO5.

- The latest measurements made by ADC0 through ADC2 .

- A set of flags indicating which event(s) triggered the I/O report.

- The settings of DAC0 and DAC1.

The I/O binding function works in conjunction with I/O event reporting. When I/O binding is enabled on a

DNT90, data received in an I/O event report it is mapped as follows:

- GPIO2 will output the state of GPIO0 in the last received event report.

- GPIO3 will output the state of GPIO1 in the last received event report.

- DAC0 will output the voltage read by ADC0 in the last received event report.

- DAC1 will output the voltage read by ADC1 in the last received event report.

I/O binding is used to transmit switch positions or analog signals from one location to another. Note that

I/O binding cannot be used in a DNT90 when SPI slave mode is enabled or differential ADC mode is

used. See Section 5.4 for recommendations on configuring I/O event reporting and binding, and Sections

7.4.6 and 7.4.7 for detailed information on I/O reporting and binding parameters.

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4.0 DNT90 System Configuration

DNT90 radios feature an extensive set of configuration options that allows them to be adapted to a wide

range of applications. Configuration defaults have been carefully selected to minimize the configuration

effort for most applications, while providing the ability to individually adjust the configuration of each radio

to achieve highly optimized system operation.

4.1 Configuration Parameters

The configuration of a DNT90 is controlled by a set of parameters (registers). Parameters that address a

particular aspect of operation are grouped into a bank. All parameters can be accessed through a mod-

ule’s serial port and over the radio link. Most parameters are read/write. Read-only parameters include

fixed values such a MAC addresses, firmware version numbers and parameters that are dynamically ad-

justed during system operation such as link status. Write-only parameters include security keys and cer-

tain action triggers such as reset. Incorrectly configuring certain parameters can disable a module’s radio

link, but the configuration can always be corrected through the serial port. The organization of the param-

eter register banks and the details of each parameter are covered in Section 7.4 of this guide. Sections

4.2 through 5.7 discuss which parameters apply to various aspects of configuring a DNT90 system, net-

work or application interface.

4.2 Configuring a Basic Point-to-Point System

A basic DNT90 point-to-point system is suitable for many serial data applications. The default config-

uration of a DNT90 is a remote with the serial port configured for transparent operation at 9.6 kbps,

8N1. To configure a basic point-to-point system:

1. Configure one of the modules as a base by setting the DeviceMode parameter in Bank 0 to 0x01.

2. Set the MemorySave parameter in Bank 0xFF to 0xD2, which will save the DeviceMode parame-

ter to EEPROM and reset the module, enabling base operation.

3. All other parameters may be left at their default values.

4.3 Configuring a Basic Point-to-Multipoint Point System

A basic DNT90 point-to-multipoint point systems is suitable for many serial data applications where

multiple remotes are used. The default configuration of a DNT90 is a remote with the serial port con-

figured for transparent operation at 9.6 kbps, 8N1. To configure a basic point-to-multipoint system:

1. Configure one of the modules as a base by setting the DeviceMode parameter in Bank 0 to 0x01.

2. If the host application driving the base will individually communicate each remote, set the Proto-

colMode parameter in Bank 4 of the base to 0x01. This step is not required if messages from the

base to the remotes will always be broadcast and/or the base does not need to know the MAC

address of the remote sending a message.

3. Set the MemorySave parameter in Bank 0xFF to 0xD2, which will save the DeviceMode parame-

ter to EEPROM and reset the module, enabling base operation.

4. All other parameters may be left at their default values.

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5. If the host application driving the base will individually communicate each remote, read or scan

the MAC addresses from the label on top of each remote and load the addresses in the host ap-

plication data base.

4.4 Configuring a Customized Point-to-Point or Point-to-Multipoint System

The DNT90 includes many configuration parameters that allow extensive customization of a point-to-point

or point-to-multipoint system. Most applications will require only a few of these parameters be changed

from their default values. But for those applications that need them, RFM recommends the following con-

figuration sequence. Skip the configuration steps where the default parameter value is satisfactory.

1. Configure one of the modules as a base by setting the DeviceMode parameter in Bank 0 to 0x01.

2. Set the optional AES security key in all system radios by loading your selected 16-byte string into

the SecurityKey parameter in Bank 0 (the default is 16 bytes of 0x00).

3. Select the frequency band of operation by setting the FrequencyBand parameter in Bank 1 of the

base radio as desired (the default is Band 0).

4. Set the transmitter power level as needed in all radios by setting the TxPower parameter in

Bank 0 (the default is 158 mW).

5. Configure the system ID in all radios by setting the SystemID parameter in Bank 0 (the default is

OK if there is no chance of overlapping systems).

6. Load the parent network ID in all remotes in the ParentNetworkID parameter in Bank 0 as needed

(wildcard default is OK for point-to-point and point-to-multipoint systems).

7. Set the BaseModeNetID parameter in the base to match the ParentNetworkID parameter in the

remotes if the default BaseModeNetID is not used in the base and the wildcard default Parent-

NetworkID is not used in the remotes.

8. For a point-to-multipoint system where DNT90 MAC addressing will be used, set the Proto-

colMode parameter in Bank 4 of the base to 0x01. Set the protocol mode as needed in the base

and remote of a point-to-point system, and as needed in the remotes in a point-to-multipoint sys-

tem. If SPI slave mode will be used, protocol mode must be enabled in all system radios. Note

that if the application data includes addressing information for individual remote hosts, the DNT90

broadcast mode can be used instead of the DNT90 protocol mode.

9. If using transparent serial mode in the system:

a. Set the remote transparent destination address in the RmtTransDestAddr parameter,

Bank 0, in each remote if the destination is not the base (the base address is the default

destination).

b. Set the transparent point-to-point mode to select either the RmtTransDestAddr address

(default) or the address of the originator of the last received message as the remote des-

tination address. The parameter that controls this destination address is the Trans-

PtToPtMode in Bank 4. Set in all remotes as needed.

c. Set the timeout for transmission of transparent data in the remotes as needed. The pa-

rameter that controls the timeout is the TxTimeout in Bank 4 (the default is no timeout).

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d. Set the minimum message length for transmission of transparent data in the remotes as

needed. The parameter that controls the length is the MinPacketLength in Bank 4 (the

default is one byte).

10. Refer to Section 4.6 below which discusses how to coordinate the values of the following four

parameters:

a. Set the maximum number of messages that can be sent in a hop on each system radio.

The parameter that controls this number is MsgsPerHop in Bank 4. The default is 8 mes-

sages.

b. Load the required base slot size into the BaseSlotSize parameter, Bank 1, in the base.

The default is 40 bytes.

c. Configure the number of child slots per hop on the base by setting the NumSlots parame-

ter. The default is 3 slots.

d. Set the required hop duration on the base. The HopDuration parameter in Bank 0 con-

trols hop duration. The default is 20 ms.

11. Configure the slot lease on the base by setting the SlotLease parameter. The default is 4 hops.

12. Set the heartbeat interval as required in each system radio. The parameter that controls heart-

beats is the HeartBeatIntrvl in Bank 0. The default is 20 seconds/heartbeat.

13. Enable end-to-end message ACKs where required by setting the EndToEndAckEnable parameter

in Bank 0 to 1. Enabling this parameter provides a confirmation that a message has reached its

destination in peer-to-peer or store-and-forward routing. The default is disabled.

14. Set the message retry limit on the base with the ArqAttemptLimit parameter in Bank 1. The de-

fault value is 6 retries.

15. Set the link drop threshold on the base by setting the LinkDropThreshold in Bank 1. This parame-

ter sets the number of sequential hops without receiving a beacon that will trigger a child to re-

synchronize and re-link to its parent. The default is 10 hops.

16. Set the point-to-point reply timeout on the base in the P2PReplyTimeout parameter in Bank 1.

The default is 16 hops. See Section 7.4.2 for parameter details.

17. Configure the registration timeout on the base by setting the RegistryTimeout parameter in

Bank 1. The default timeout is 50 hops. See Section 7.4.2 for a discussion of this parameter.

18. Load an optional “friendly description” in each system radio in the UserTag parameter, Bank 0.

4.5 Configuring a Store-and-Forward System

The following additional parameters must be set to configure a DNT90 store-and-forward system:

1. Configure the DNT90 radios designated to be routers by setting the DeviceMode parameter

in Bank 0 to 0x02.

2. Enable store-and-forward operation on all system radios by setting the Store&ForwardEn

parameter in Bank 0 to 0x01.

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3. In each router, load a unique base-mode network ID into the BaseModeNetID parameter in Bank

0, and into the base if a router is set to 0x00.

4. To configure a specific system topology, set the parent network ID parameter, ParentNwkID, and

optionally the alternate parent network ID parameter, AltParentNwkID, in all routers and

remotes. Note that a store-and-forward system topology can be formed either automatically or

manually, based on the settings of the ParentNetworkID and optionally the AltParentNwkID

parameters:

- Setting the ParentNwkID parameter to 0xFF in all routers and remotes allows each

router and remote to automatically link to a parent, causing the system to form

automatically (child routers picking each other as a parent cannot occur). In this case, the

AltParent-NwkID parameter should be set to 0xFF, which disables it.

- Setting the ParentNwkID and optionally the AltParentNwkID parameters to specific val-

ues in each router and remote allows full manual control of the network topology.

The benefit of automatic system formation is self-healing. If a parent router fails, its child nodes

can re-link to any other parent router they can receive. However, automatic topology formation

can result in an unnecessary number of hops between routers or remotes and the base.

The benefit of manual system topology formation is to avoid unnecessary extra hops in the sys-

tem, and to balance the number of children supported by each parent router. If a parent router

fails and an active alternate parent network ID has not been assigned, all children downstream

from the failure will be off the system until the failed router is repaired or replaced.

4.6 Slot Buffer Sizes, Number of Slots, Messages per Hop and Hop Duration

The base slot size (BSS) sets the maximum number of payload bytes the base can transmit during a sin-

gle hop when the base is sending one message per hop. The maximum BSS is 105 bytes when a DNT90

system is configured for one slot. Adding additional slots reduces the maximum BSS by three bytes per

slot. The BSS buffer is set nine bytes larger than the BSS, to a maximum of 114 bytes. The base can po-

tentially send more than one message per beacon, up to the limit set by its MsgsPerHop parameter value.

Each message in the BSS buffer occupies nine header bytes plus the payload.

For example, the base can send three messages per hop when the BSS is 90 bytes, provided the total

payload bytes in the three messages is 72 bytes or less:

slot size = 90

buffer = 90 + 9 = 99

3 headers = 3*9 = 27

net for payload = 99 - 27 = 72

The BSS must be large enough to accommodate any protocol-formatted message that may be sent over

the wireless link, as each protocol-formatted message must be sent in a single transmission.

The remote slot size (RSS) is the maximum number of payload bytes a child can transmit during a single

hop when it is sending one message per hop. The RSS is the same for all slots. The maximum RSS is

109 bytes. The RSS buffer is set nine bytes larger than the RSS, to a maximum of 118 bytes. A child can

potentially send more than one message in a slot, up to the limit set by its MsgsPerHop parameter value.

Each message in the transmit buffer occupies nine header bytes plus the payload. For example, a child

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can send two messages per hop when the RSS is 73 bytes, provided the total payload bytes in the two

messages is 64 bytes or less:

slot size = 73

buffer = 73 + 9 = 82

2 headers = 2*9 = 18

net for payload = 82 - 18 = 64

Note that the RSS is calculated by all DNT90s in a system, rather than being a user configured parame-

ter. The slot size depends on the current values of the following parameters:

- base slot size

- hop duration

- number of slots in a frame

The system must be configured such that the RSS is big enough to hold the longest protocol message a

remote will send. This is done by setting the appropriate hop duration for the chosen BSS and number of

slots. The required hop duration for a specific number of slots, base slot size and remote slot size is cal-

culated as follows:

HD hop duration in µs

NS number of slots

BSS base slot size in bytes

RSS remote slot size in bytes

HD = NS*(80*RSS + 2440) + 80*BSS + 3280 (round HD up to an even multiple of 500 µs)

Example:

NS = 4

BSS = 96

RSS = 109

HD = 4*(80*109 + 2440) + 80*96 + 3280

HD = 44640 + 7680 + 3280

HD = 55600 round to 56000 µs = 56 ms

Excel Formatted Equations (load the Excel analysis ToolPak add-in for the QUOTIENT function):

A B C D E

1 Slots BSS RSS Hop Duration in µs Hop Duration in ms, Rounded

2 Up to the next 0.5 ms Step

3 1 20 20 =A3*(80*C3+2440) + 80*B3 + 3280 =0.5*QUOTIENT((D3+499),500)

For transparent serial port operation without using hardware flow control, the BSS and RSS must be large

enough to accommodate all message bytes that can accumulate between transmissions. The required

BSS and RSS for protocol-formatted messages sent over the wireless link are shown in Table 7.3.1. For

example, the BSS and RSS size required for a TxData protocol-formatted message is three bytes less

than the value in the length byte field of the formatted message.

The default BSS is 40 bytes, number of slots is 3 and hop duration is 20 ms. These parameter settings

provide a 25 byte RSS. These default settings are suitable for point-to-point and small to medium point-

to-multipoint systems operating with protocol-formatted and/or transparent messages. To accommodate

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all configuration commands, replies, event messages and announce messages, a 20 byte minimum slot

size is required.

The NumSlots and the MsgsPerHop parameters both affect the number of messages that can be sent on

each hop. The distinction between these parameters is as follows:

- The NumSlots parameter controls the maximum number of individual children that can send

messages to a parent on each hop.

- The MsgsPerHop parameter controls the maximum number of messages a parent or child can

send on each hop.

The NumSlots parameter is configurable only for the base. The base then communicates the NumSlots

value to all other radios in its system. The NumSlots parameter can be set to one for a point-to-point sys-

tem, as there is only one child radio. The NumSlots parameter can be set to allow up to eight children to

send messages to their parent during a hop. As discussed above, the hop duration must be increased as

the number of slots are increased to achieve a specific RSS. The default NumSlots parameter value of

three is suitable for many applications.

De facto TDMA operation (guaranteed bandwidth) can be implemented for up to 8 remotes by setting the

SlotLease parameter to a value greater than any gaps in data being sent to a remote by its local host.

This will insure that the base keeps each remote’s slot reserved for it even when there is a gap in the da-

ta.

The MsgsPerHop parameter is configurable for each DNT90 in a system. This parameter is usually set to

a high value in the base and the routers, allowing traffic between a parent and multiple children on each

hop. The MsgsPerHop parameter has little effect in remotes except when a remote needs to send multi-

ple peer-to-peer messages during a hop. To support sending multiple messages on each hop, the BSS

and RSS must be sized accordingly, requiring a longer hop duration. Note that the messages must be

protocol messages and all messages to be sent on a single hop must be in the module before the module

begins to transmit.

5.0 DNT90 Application Interface Configuration

DNT90 modules include a comprehensive set of application interfaces and related options that support a

wide range of applications including wireless RS232/485 cable replacements, wireless sensor networks,

wireless alarm systems and industrial remote control applications. Recommended configuration steps for

each application interface are discussed in Sections 5.1 through 5.7 below.

5.1 Configuring the Serial Port

The default serial port configuration is 9.6 kbps, 8-bit data, no parity and 1 stop bit.

1. Configure the serial data rate as required from 1.2 to 250 kbps by setting the SerialRate

parameter in Bank 3.

2. Configure the parity and number of stop bits by setting the SerialParams parameter in Bank 3.

3. Enable/disable serial port hardware flow control as required by setting the GpioAlt parameter in

Bank 6. Hardware flow control is disabled by default, but is recommended when operating at

higher baud rates and/or sending large blocks of data.

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5.2 Configuring the SPI Port

1. Enable either SPI master mode or SPI slave mode by setting the SpiMode parameter in Bank 3.

The serial port remains operational in SPI master mode but is disabled in SPI slave mode.

2. If using SPI master mode:

a. Select the SPI clock rate by setting the SpiRateSel parameter in Bank 3 (default

is 125 kbps)

b. Set the SPI master command string and string length by setting the SpiMasterCmdStr

and SpiMasterCmdLen parameters respectively in Bank 3.

3. Configure the edge trigger direction, bit-sampling edge and bit-order options by setting the

SpiOptions parameter in Bank 3.

5.3 Configuring Digital I/O

1. GPIO2 through GPIO 5 have configurable alternate functions as discussed in Section 7.4.7. Se-

lect either digital (state) functionality or alternate functionality for each of these pins by setting the

GpioAlt parameter in Bank 6. Note that selecting SPI slave mode overrides the GpioAlt parameter

setting for GPIO3 though GPIO5.

2. Configure the direction of each GPIO pin as needed by setting the GpioDir parameter in Bank 6

(the default is all inputs).

3. Configure the direction of each GPIO pin for sleep mode as needed by setting the GpioSleepDir

parameter in Bank 6 (the default is all inputs).

4. Set the initial state (power on) of all GPIO pins configured as outputs by setting the GpioInit pa-

rameter in Bank 6 (the default is all logic low).

5. Set the state of all GPIO pins configured as outputs in sleep mode by setting the GpioSleepState

parameter in Bank 6 (the default is all logic low).

6. GPIO0 through GPIO3 can trigger I/O event reporting when functioning as digital inputs. Enable

event report triggering and optional sleep hold-off for these pins by setting the GpioEdgeTrigger

parameter in Bank 6.

5.4 Configuring Analog I/O

1. Select the ADC full-scale reference by setting the AdcReference parameter in Bank 6. This set-

ting applies to all ADC channels. The default is the ADC_EXT_REF input. If ADC operation is not

needed, setting this parameter to 0x03 disables ADC operation, reducing current consumption.

2. Select the ADC mode, either single-ended or differential by setting the AdcDiffMode parameter in

Bank 6. The default is single-ended ADC operation.

3. If differential ADC mode is selected, set the desired ADC preamplifier gain for each ADC channel

with the AdcGainCh0 and AdcGainCh1 parameters in Bank 6. The default gain is 1. Note that the

full scale output voltage from the preamplifier is 2.4 V.

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4. Reconfigure the ADC measurement interval as needed by setting the AdcSampleIntvl parameter.

The default is 100 ms, and applies to all ADC channels.

5. Set the AdcAveSelect parameter to the number of ADC readings to be averaged to produce a

measurement. The larger the AdcAveSelect parameter is set, the greater the noise filtering effect,

but the longer it takes to produce a measurement. Setting this parameter to 8 or more when the

ADC is operating in single-ended mode is especially helpful in stabilizing ADC measurements.

6. Measurements on each ADC input can be compared to high/low threshold values, triggering an

I/O event report if the measurements go above/below the respective thresholds. The thresholds

for each ADC channel are set by loading the AdcXThresholdLo and AdcXThresholdHi, where X

refers to the ADC channel designator, 0 through 2. When the ADC is operating in differential

mode, the ADC1 to ADC0 differential measurement is compared to the “0” high and low thresh-

olds, and the ADC2 to ADC0 differential measurements is compared to the “1” high and low

thresholds. In this case the “2” threshold values are not used.

7. Set the IoPreDelay parameter as needed in Bank 6 to allow signals to stabilize following a mod-

ule wakeup event.

8. Set the AdcSkipCount parameter in Bank 6 as needed to allow internal transients in the ADC

sample-and-hold circuit to settle out. This parameter must be set to at least 3 when AdcDiffMode

is selected. Note that the IoPreDelay parameter discussed above provides a delay to allow sig-

nals external to the DNT90 to settle following an event, while AdcSkipCount skips measurements

that may be distorted because the internal voltage on the ADC sample-and-hold has not settled.

9. Select the DAC full scale reference by setting DacReference in Bank 6. This setting applies to

both DAC channels. The default is the ADC_EXT_REF input. If DAC operation is not needed, set-

ting this parameter to 0x03 will disable DAC operation, reducing current consumption.

10. Configure the initial (power on) output level for DAC0 and DAC1 by loading the initial settings in

the Dac0Init and Dac1Init parameters respectively.

The ADC and DAC channels are factory calibrated. It may be desirable to fine tune these calibrations

after the DNT90 has been integrated with the customer’s hardware in some applications. For analog

calibration support, contact RFM technical support.

5.5 Configuring I/O Event Reporting and I/O Binding

1. Select the analog, digital and timing events that will trigger an I/O event report by setting the

respective bits in the IoReportTrigger parameter in Bank 6. The default is no triggers set.

2. Configure the trigger behavior bits in the GpioEdgeTrigger parameter, Bank 6, for each GPIO

input selected to generate an I/O event report.

3. For each ADC channel selected to generate an I/O event, set the high and low measurement

threshold values. The AdcThreshold parameters are in Bank 6. When the ADC is operating in dif-

ferential mode, the ADC1 to ADC0 differential measurement is compared to the “0” high and low

thresholds, and the ADC2 to ADC0 differential measurements is compared to the “1” high and low

thresholds. In this case the “2” threshold values are not used.

4. If the periodic timer has been selected to generate an event report, load the required timer report

interval into the IoReportInterval parameter in Bank 6. The default timer interval is 30 seconds.

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5. Set the MaxQueuedEvents parameter in Bank 6 as needed to limit the number of Event Reports

that can be queued at one time by a DNT90. This parameter is used to prevent a router device

from clogging up its outbound queue with its own pending transmissions if it has having trouble

obtaining link or an available slot from its parent.

6. If I/O binding operation is desired, set the IoBindingEnable parameter in Bank 6 to 0x01.

I/O binding is disabled by default, and cannot be used when the ADC is operating in

differential mode.

5.6 Configuring Sleep Mode

Sleep mode can be used in conjunction with I/O reporting to greatly extend battery life on DNT90 re-

motes. At least one I/O report trigger must be enabled to allow sleep mode to be used. Note that the

base and routers cannot be configured for sleep mode.

1. Enable sleep mode as desired in each remote by setting the SleepModeEn parameter in Bank 0 to 1.

2. Configure the timeout for a remote to attempt to link to its parent when triggered awake. This is done

by setting the WakeLinkTimeout parameter in Bank 0. The default timeout is 5 seconds.

3. Configure the maximum time a remote in sleep mode will remain awake following linking, receiving an

ACK, processing a message addressed to it, or receiving a serial or SPI message by setting the

Wake-ResponseTime parameter. The default response time is 500 ms. Note that the setting of this

parameter is overridden by some GpioEdgeTrigger parameter settings.

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6.0 DNT90 Hardware

1 8 1 9 2 0 2 1 2 2 2 31 71 6 2 4 2 5 2 6

1 5

1 4

1 3

1 2

1 1

1 0

D N T 9 0 B l o c k D i a g r a m

2 7

M i c r o c o n t r o l l e r

R e g

G N D

A C T ( D I A G _ T X )

/ D C D ( D I A G _ R X )

G P I O 0

R A D I O _ T X D

R A D I O _ R X D

G P I O 4 ( / H O S T _ C T S )

G P I O 5 ( / H O S T _ R T S )

DAC0

G P I O 2

G P I O 1

G P I O 3 ( D A V )

DAC1

V C C

G N D

/ R E S E T

ADC1

M I S O

M O S I

/ S S

S C L K

3 . 3 V _ O U T

A D C _ E X T _ R E F

ADC0

+ 3 . 3 V

2 8 2 9 3 0

G N D

R S V D

T R C 1 0 3

I R Q 0

I R Q 1 / D C L K

D A T A

P L L _ L O C K

S C K

S D I

S D O

n S S _ D A T A

n S S _ C O N F I G

S A W F i l t e r

a n d

P o w e r A m p

R S V D

Figure 6.0.1

The major components of the DNT90 include an RFM TRC103 900 MHz FHSS transceiver and a low cur-

rent 8-bit microcontroller. The DNT90 operates in the 902 to 928 MHz ISM band. There are four se-

lectable hopping patterns providing compatibility with frequency allocations in North America, South

America and Australia. The DNT90 also has two selectable RF output power levels: +16 dBm (40 mW)

and +22 dBm (158 mW).

The DNT90 receiver is protected by a low-loss SAW filter, providing an excellent blend of receiver sensi-

tivity and out-of-band interference rejection that is especially important in outdoor applications.

The DNT90 provides a variety of hardware interfaces. There are two serial ports plus one SPI port. Either

the primary serial port or the SPI port can be selected for data communications. The second serial port is

dedicated to diagnostics. The primary and diagnostic serial ports support most standard baud rates up to

250 kbps. The SPI port supports data rates up to 500 kbps. Also included are three ADC inputs, two DAC

outputs and six general-purpose digital I/O ports. Four of the digital I/O ports support an optional interrupt-

from-sleep mode when configured as inputs.

There are four module configurations in the DNT24 Series:

- The DNT90C is designed for use with an external antenna and for solder reflow mounting.

- The DNT90P is designed for use with an external antenna and for plug-in connector mounting.

- The DNT90CA has a built-in chip antenna and is designed for solder reflow mounting.

- The DNT90PA has a built-in chip antenna and is designed for plug-in connector mounting.

www.RFM.com Technical support +1.678.684.2000 Page 28 of 82

6.1 Specifications

Absolute Maximum Rating Value Units

Power Supply Input -0.5 to +6.5 V

All Input/Output Pins -0.5 to +3.3 V

Input Power to RFIO Port 0 dBm

Non-operating Ambient Temperature Range -40 to +85 oC

Table 6.1.1

Operating Characteristic Sym Minimum Typical Maximum Units

Operating Frequency Range 902.76 927.24 MHz

Hop Duration 8 100 ms

Number of RF Channels 25, 26 or 52

Modulation FSK

RF Data Transmission Rate 100 kbps

Receiver Sensitivity, 10-5 BER -100 dBm

Transmitter RF Output Power 40 or 158 mW

Optimum Antenna Impedance 50 Ω

RF Connection U.FL Connector

Network Topologies Point-to-Point, Point-to-Multipoint,

Peer-to-Peer and Store-and-Forward

Access Scheme Ad Hoc TDMA

ADC Input Range 0 2.7 V

ADC Input Resolution 12 bits

ADC Sample Rate 100 Hz

Signal Source Impedance for ADC Reading 10 KΩ

ADC External Reference Voltage Range 1.0 2.7 V

DAC Output Range 0 3.3 V

DAC Output Resolution 12 bits

Primary and Diagnostic Serial Port Baud Rates 1.2, 2.4, 4.8, 9.6, 19.2, 14.4 28.8, 38.4,

57.6, 115.2, 230.4, 250 kbps

Master Serial Peripheral Interface Data Rate 125 250 500 kbps

Slave Serial Peripheral Interface Data Rate 4000 kbps

Digital I/O:

Logic Low Input Level -0.5 0.8 V

Logic High Input Level 2.45 3.3 V

Logic Input Internal Pull-up Resistor 20 KΩ

Power Supply Voltage Range VCC +3.3 +5.5 Vdc

Power Supply Voltage Ripple 10 mVP-P

Peak Transmit Mode Current, 158 mW Output 170 mA

Average Operating Current, 158 mW TX Output:

Base, Continuous Data Stream 110 mA

Remote, Linked, No Data 15 mA

Remote, Continuous Data Stream 25 mA

Sleep Current 3 6 µA

Operating Temperature Range -40 85 oC

Operating Relative Humidity Range (non condensing) 10 90 %

Table 6.1.2

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6.2 Module Pin Out

Electrical connections to the DNT90C are made through the I/O pads and through the I/O pins on the

DNT90P. The hardware I/O functions are detailed in the table below:

Pin Name I/O Description

1 GND -

Power supply and signal ground. Connect to the host circuit board ground.

2 ACT

(DIAG_TX)

(O)

This pin’s default configuration is data activity output. On a base, this signal blinks when a valid

packet is received. On a remote, this signal blinks when a packet is transmitted. On a router, this

signal blinks when a valid upstream packet is received or a downstream packet is transmitted.

Alternate pin function is the diagnostic serial port output.

3 /DCD

(DIAG_RX)

(I)

This pin’s default configuration is a data carrier detect output. On a base, this signal is asserted

when any valid packet is received, and is cleared if no packets are heard for the configured rout-

er/remote registration time-out interval. On a router or remote, this signal is asserted when the

radio obtains hopping pattern synchronization, and remains asserted until no beacons are heard

for 50 hops. Alternate pin function is the diagnostic serial port input.

4 GPIO0 I/O

Configurable digital I/O port 0. When configured as an input, an internal pull-up resistor can be

selected and direct interrupt from sleep can be invoked. When configured as an output, the power-

on state is configurable. In sleep mode the pin direction, input pull-up selection or output state are

also separately configurable.

5 RADIO_TXD O

Serial data output from the radio.

6 RADIO_RXD I Serial data input to the radio.

7 GPOI4

(/HOST_CTS)

I/O

(O)

GPIO4 with the same configuration options as GPIO2. Alternate pin function is UART/SPI flow

control output. The module sets this line low when it is ready to accept data from the host on the

RADIO_RXD or MOSI input. When the line goes high, the host must stop sending data.

8 GPIO5

(/HOST_RTS)

I/O

(I)

GPIO5 with the same configuration options as GPIO2. Alternate pin function is UART/SPI flow

control input. The host sets this line low to allow data to flow from the module on the RADIO_TXD

pin. When the host sets this line high, the module will stop sending data to the host.

9 DAC0 O

12-bit DAC 0 output. Full scale can be referenced to the voltage at pin 25, or the 3.3 V regulated

module bus voltage.

10 GPIO2 I/O

Configurable digital I/O port 2. Same configuration options as GPIO0.

11 GPIO1 I/O

Configurable digital I/O port 1. Same configuration options as GPIO0.

12 GPIO3

(DAV)

I/O

(O)

Default pin function is GPIO3 with the same configuration options as GPIO0. When SPI slave

mode operation is enabled, a logic high on this pin indicates when data is available to be clocked

out by the SPI master.

13 DAC1 O

12-bit DAC 1 output. Same specifications and configuration options as DAC0.

14 VCC I

Power supply input, +3.3 to +5.5 Vdc.

15 GND -

Power supply and signal ground. Connect to the host circuit board ground.

16 GND -

Power supply and signal ground. Connect to the host circuit board ground.

17 /RESET I

Active low module hardware reset.

18 ADC0 I

ADC input 0. This pin is a direct ADC input when the ADC is operating in single-ended mode, or

the differential negative input for positive inputs applied to ADC1 or ADC2 when the ADC is operat-

ing in differential mode. Full-scale reading can be referenced to Pin 25 for ratiometric measure-

ments. For absolute measurements, the ADC can use the regulated supply voltage divided by 1.6

(about 2.06 V), or an external voltage applied to Pin 25. In single-ended mode, ADC measure-

ments are 11-bit unsigned values with full scale nominally 2.7 V when referenced to a 2.7 V input

on Pin 27. In differential mode, ADC measurements are 12-bit signed values.

19 ADC1 I

ADC input 1. Direct input when the ADC is operating in single-ended mode, positive differential

input relative to ADC0 when the ADC is operating in differential mode.

20 MISO I/O

This pin is the SPI master mode input or slave mode output.

21 MOSI I/O

This pin is the SPI master mode output or slave mode input.

22 /SS I/O

SPI active low slave select. This pin is an output when the module is operating as a master, and an

input when it is operating as a slave.

23 SCLK I/O

SPI clock signal. This pin is an output when operating as a master, and an input when operating as

a slave.

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Pin Name I/O Description (continued)

24 ADC2 I

ADC input 2. Direct input when the ADC is operating in single-ended mode, positive differential

input relative to ADC0 when the ADC is operating in differential mode.

25 ADC_EXT_

REF I/O

ADC external reference voltage pin. The voltage at this pin can be used by the ADCs as a refer-

ence for ratiometric measurements. With no external voltage or load applied, this pin presents a

nominal 2.7 V output through a 2.126 K source resistance. A low impedance external reference

voltage in the range of 1.0 to 2.7 V may be applied to this pin as an option.

26 RSVD -

Reserved pin. Leave unconnected.

27 RSVD -

Reserved pin. Leave unconnected.

28 GND -

Connect to the host circuit board ground plane.

29 RSVD -

Reserved pin. Leave unconnected.

30 GND -

Connect to the host circuit board ground plane.

Table 6.2.1

6.3 Antenna Connector

A U.FL miniature coaxial connector is provided on both DNT90 configurations for connection to the RFIO

port. A short U.FL coaxial cable can be used to connect the RFIO port directly to an antenna. In this case

the antenna should be mounted firmly to avoid stressing the U.FL coaxial cable due to antenna mounting

flexure. Alternately, a U.FL coaxial jumper cable can be used to connect the DNT90 module to a U.FL

connector on the host circuit board. The connection between the host circuit board U.FL connector and

the antenna or antenna connector on the host circuit board should be implemented as a 50 ohm

C o p p e r

G r o u n d

P l a n e

C o p p e r

S t r i p l i n e

T r a c e

F R - 4 P C B

M a t e r i a l

C i r c u i t B o a r d S t r i p l i n e T r a c e D e t a i l

F o r 5 0 o h m i m p e d a n c e W = 1 . 7 5 * H

Figure 6.3.1

Trace Separation from

50 ohm Microstrip

Length of Trace Run

Parallel to Microstrip

100 mil 125 mill

150 mil 200 mil

200 mil 290 mil

250 mil 450 mil

300 mil 650 mil

Table 6.3.2

stripline. Referring to Figure 6.3.1, the width of this stripline depends on the thickness of the circuit board

between the stripline and the groundplane. For FR-4 type circuit board materials (dielectric constant of

4.7), the width of the stripline is equal to 1.75 times the thickness of the circuit board. Note that other cir-

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cuit board traces should be spaced away from the stripline to prevent signal coupling, as shown in Table

6.3.2. The stripline trace should be kept short to minimize its insertion loss.

6.4 Power Supply and Input Voltages

DNT90 radio modules can operate from an unregulated DC input (Pad 19) in the range of 3.3 to 5.5 V

with a maximum ripple of 5% over the temperature range of -40 to 85 °C. Applying AC, reverse DC, or a

DC voltage outside the range given above can cause damage and/or create a fire and safety hazard. Fur-

ther, care must be taken so logic inputs applied to the radio stay within the voltage range of 0 to 3.3 V.

Signals applied to the analog inputs must be in the range of 0 to ADC_EXT_REF (Pad/Pin 25). Applying a

voltage to a logic or analog input outside of its operating range can damage the DNT90 module.

6.5 ESD and Transient Protection

The DNT90C and DNT90P circuit boards are electrostatic discharge (ESD) sensitive. ESD precautions

must be observed when handling and installing these components. Installations must be protected from

electrical transients on the power supply and I/O lines. This is especially important in outdoor installations,

and/or where connections are made to sensors with long leads. Inadequate transient protection can result

in damage and/or create a fire and safety hazard.

6.6 Interfacing to 5 V Logic Systems

All logic signals including the serial ports on the DNT90 are 3.3 V signals. To interface to 5 V signals, the

resistor divider network shown in Figure 3.7.1 below must be placed between the 5 V signal outputs and

the DNT90 signal inputs. The output voltage swing of the DNT90 3.3 V signals is sufficient to drive 5 V

logic inputs.

5 V

L o g i c D N T 5 0 0

2 . 2 K

4 . 3 K

Figure 6.6.1

6.7 Mounting and Enclosures

DNT90C and DNT90CA radio modules are mounted by reflow soldering them to a host circuit board.

DNT90P and DNT90PA modules are mounted by plugging their pins into a set of mating connectors on

the host circuit board. Refer to Section 8.3 and/or the DNT90 and DNT90A data sheets for connector de-

tails.

DNT90 enclosures must be made of plastics or other materials with low RF attenuation to avoid compro-

mising antenna performance where antennas are internal to the enclosure. Metal enclosures are not suit-

able for use with internal antennas as they will block antenna radiation and reception. Outdoor enclosures

must be water tight, such as a NEMA 4X enclosure.

DNT90

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6.8 Labeling and Notices

DNT90 FCC Certification - The DNT90 hardware has been certified for operation under FCC Part 15

Rules, Section 15.247. The antenna(s) used for this transmitter must be installed to provide a separation

distance of at least 20 cm from all persons and must not be co-located or operating in conjunction with

any other antenna or transmitter.

DNT90 FCC Notices and Labels - This device complies with Part 15 of the FCC rules. Operation is sub-

ject to the following two conditions: (1) this device may not cause harmful interference, and (2) this device

must accept any interference received, including interference that may cause undesired operation.

A clearly visible label is required on the outside of the user’s (OEM) enclosure stating the following text:

Contains FCC ID: HSW-DNT90

Contains IC: 4492A-DNT90

RFM (Insert Model Designation DNT90C, DNT90CA, DNT90P or DNT90PA depending on the model

used): This device complies with Part 15 of the FCC Rules. Operation is subject to the following two con-

ditions: (1) This device may not cause harmful interference, and (2) this device must accept any interfer-

ence received, including interference that may cause undesired operation.

WARNING: This device operates under Part 15 of the FCC rules. Any modification to this device, not

expressly authorized by RFM, Inc., may void the user’s authority to operate this device.

This apparatus complies with Health Canada’s Safety Code 6 / IC RSS 210.

IC RSS-210 Notice - Operation is subject to the following two conditions: (1) this device may not cause

interference, and (2) this device must accept any interference, including interference that may cause un-

desired operation of the device.

ICES-003

This digital apparatus does not exceed the Class B limits for radio noise emissions from digital apparatus

as set out in the radio interference regulations of Industry Canada.

Le present appareil numerique n’emet pas de bruits radioelectriques depassant les limites applicables

aux appareils numeriques de Classe B prescrites dans le reglement sur le brouillage radioelectrique

edicte par Industrie Canada.

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7.0 DNT90 Protocol-formatted Messages

7.1 Protocol Formats

DNT90 modules can work in one of two serial data modes - transparent or protocol. Transparent mode

requires no data formatting, but is limited to sending data to either a single destination or broadcasting

data to all destinations. A node that needs to send messages to individual destinations must use protocol

formatting unless the data being sent includes addressing information. Protocol formatting is also required

for configuration commands and replies, and sensor I/O commands, replies and events. All protocol-

formatted messages have a common header as shown in Figure 7.1.1:

0 1 2 3 …

SOP Length PktType variable number of arguments …

Figure 7.1.1

The scale above is in bytes.

The Start-of-Packet (SOP) character, 0xFB, is used to mark the beginning of a protocol-formatted mes-

sage and to assure synchronization in the event of a glitch on the serial port at startup.

The Length byte is defined as the length of the remainder of the message following the length byte itself,

or the length of the entire message - 2.

The Packet Type (PktType) byte specifies the type of message. It is a bitfield-oriented specifier, decoded

as follows:

Bits 7..6 Reserved for future use

Bit 5 Event - this bit is set to indicate an event message

Bit 4 Reply - this bit is set to indicate a message is a reply

Bits 3..0 Type - these bits indicate the message type

As indicated, the lower four bits (3..0) specify a message type. Bit 4 indicates that the message is a reply.

A reply message has the original command type in bits 3..0, with Bit 4 set to one. Bit 5 indicates an event

message. Arguments vary in size and number depending on the type of message and whether it is a

message sent from the host, or is a reply or event message from the radio. See Section 7.3 below.

7.2 Message Types

Messages generated on the serial interface by the user are referred to as host messages. Messages

generated on the serial interface by the radio are referred to as reply or event messages. Host messages

carry commands. For most commands, there is a corresponding reply message. For example, when the

host sends a TxData command message, the radio can return a TxDataReply message to indicate the

status of the transmission - whether it succeeded or failed. To assist in interpreting the command-reply

data flow, the direction is indicated by the high nibble in the message type. For example, an EnterProto-

colMode command from the host is a message type 0x00, and the EnterProtocolModeReply from the ra-

dio is a message type 0x10.

Event messages from a DNT90, such as received data or status announcements make up a third catego-

ry of messages. Event messages, including RxData, RxEvent and Announce packets are indicated by

0x20 in the high nibble of the type byte. If multiple arguments are to be provided, they are to be concate-

nated in the order shown in Section 7.3 below. Little-Endian byte order is used for all multi-byte

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arguments except text strings. Little-Endian byte order places the lowest order byte in the left-most byte

of the argument and the highest order byte in the right-most byte of the argument.

7.3 Message Format Details

Table 7.3.1 below summarizes the DNT90 protocol-formatted messages:

Command Reply Event Type Direction Min Slot Size

0x00 - -

EnterProtocolMode from Host N/A

- 0x10 -

EnterProtocolModeReply from Radio N/A

0x01 - -

ExitProtocolMode from Host N/A

0x02 - -

DeviceReset from Host N/A

- 0x12 -

DeviceResetReply from Radio N/A

0x03 - -

GetRegister from Host N/A

- 0x13 -

GetRegisterReply from Radio N/A

0x04 - -

SetRegister from Host N/A

- 0x14 -

SetRegisterReply from Radio N/A

0x05 - -

TxData from Host length value -0x03

- 0x15 -

TxDataReply from Radio 0x01

0x06 - -

GetRemoteRegister from Host 0x03

- 0x16 -

GetRemoteRegisterReply from Radio 0x14

0x07 - -

SetRemoteRegister from Host 0x13

- 0x17 -

SetRemoteRegisterReply from Radio 0x04

- - 0x26

RxData from Radio length value -0x03

- - 0x27

Announce/Error from Radio 0x07

- - 0x28

RxEvent from Radio 0x0D

Table 7.3.1

EnterProtocolMode command and reply format details are presented in Tables 7.3.2 and 7.3.3:

Enter Protocol Mode Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x07 = Number of bytes in message following this byte

0x02 Packet Type 0x00 = EnterProtocolMode

0x03 - 0x08 Payload String = “DNTCFG” or 0x44 0x4E 0x54 0x43 0x46 0x47

Table 7.3.2

Enter Protocol Mode Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x01 = Number of bytes in message following this byte

0x02 Packet Type 0x10 = EnterProtocolModeReply

Table 7.3.3

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ExitProtocolMode command format details are shown in Table 7.3.4:

Exit Protocol Mode Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x01 = Number of bytes in message following this byte

0x02 Packet Type 0x01 = ExitProtocolMode

Table 7.3.4

DeviceReset command and reply format details are shown in Tables 7.3.5 and 7.3.6:

Device Reset Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x02 = Number of bytes in message following this byte

0x02 Packet Type 0x02 = DeviceReset

0x03 Reset Type

0x00 = Normal Device Reset

0x01 = Reset to Serial Bootloader

0x02 = Reset to Over-the-Air Bootloader

Table 7.3.5

Device Reset Reply

Byte Offset Field Description

0x00 Start-Of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x01 = Number of bytes in message following this byte

0x02 Packet Type 0x12 = DeviceResetReply

Table 7.3.6

GetRegister command and reply format details are shown in Tables 7.3.7 and 7.3.8:

Get Register Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x04 = Number of bytes in message following this byte

0x02 Packet Type 0x03 = GetRegister

0x03 Register Offset Register offset in its bank

0x04 Register Bank Register bank number

0x05 Register Size Register size in bytes, only one parameter at a time (wrong register size will

produce an error response)

Table 7.3.7

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Get Register Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x05 to 0x20 = Number of bytes in message following this byte

0x02 Packet Type 0x13 = GetRegisterReply

0x03 Register Offset Register offset in its bank

0x04 Register Bank Register bank number

0x05 Register Size Register size in bytes

0x06 - 0x15 Register Value Register value, all bytes in the register (only one parameter at a time)

Note: an Error message will be returned instead of a GetRegisterReply in case of a format error.

Table 7.3.8

SetRegister command and reply format details are shown in Tables 7.3.9 and 7.3.10:

Set Register Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x05 to 0x20 = Number of bytes in message following this byte

0x02 Packet Type 0x04 = SetRegister

0x03 Register Offset Register offset in its bank

0x04 Register Bank Register bank number

0x05 Register Size Register size in bytes

0x06 - 0x15 Register Value Register value, all bytes in the register (only one parameter at a time)

Table 7.3.9

Set Register Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x01 = Number of bytes in message following this byte

0x02 Packet Type 0x14 = SetRegisterReply

Note: an Error message will be returned instead of a SetRegisterReply in case of a format error.

Table 7.3.10

TXData command and reply format details are shown in Tables 7.3.11 and 7.3.12:

TX Data Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length = Number of bytes in message following this byte

0x02 Packet Type 0x05 = TxData

0x03 - 0x05 Destination MAC Address Destination MAC address, in Little Endian byte order

0x06 - 0x72 Tx Data Up to 109 bytes of data to Base, or 105 bytes from Base

Table 7.3.11

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TX Data Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x07 = Number of bytes in message following this byte

0x02 Packet Type 0x15 = TxDataReply

0x03 - 0x05 Destination MAC Address Destination MAC address, in Little Endian byte order

0x06 Status

0x00 = ACK received from destination

0x01 = no ACK received from destination (NAK)

0x02 = “Device Not Linked” error

0x07 RSSI Packet RX power in dBm, -128 to 126 or 127 if invalid

Note: TxDataReply messages are only returned to the host when the EndToEndAckEnable parameter is set to 0x01.

Table 7.3.12

GetRemoteRegister command and reply details are shown it Tables 7.3.13 and 7.3.14:

Get Remote Register Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x07 = Number of bytes in message following this byte

0x02 Packet Type 0x06 = GetRemoteRegister

0x03 - 0x05 Destination MAC Address Destination MAC address, in Little Endian byte order

0x06 Register Offset Register offset in its bank

0x07 Register Bank Register bank number

0x08 Register Size Register size in bytes, only one parameter at a time (wrong register size will

produce an error response)

Table 7.3.13

Get Remote Register Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x0A to 0x25 = Number of bytes in message following this byte

0x02 Packet Type 0x16 = GetRemoteRegisterReply

0x03 Status Error status (0x00 = No Error, 0xE1 = Invalid Argument)

0x04 - 0x06 Originator MAC Address Originator’s MAC address, in Little Endian byte order

0x07 RSSI (-128 to 126 or 127 if invalid)

0x08 Register Offset* Register offset in its bank

0x09 Register Bank* Register bank number

0x0A Register Size* Register size in bytes

0x0B - 0x1A Register Value* Register value, all bytes in the register (only one parameter at a time)

*Bytes eight through the end of the message will not be returned in case of an error

Table 7.3.14

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SetRemoteRegister command and reply format details are shown in Tables 7.3.15 and 7.3.16:

Set Remote Register Command

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length Number of bytes in message following this byte

0x02 Packet Type 0x07 = SetRemoteRegister

0x03 - 0x05 Destination MAC Address Destination MAC address, in Little Endian byte order

0x06 Register Offset Register offset in its bank

0x07 Register Bank Register bank number

0x08 Register Size Register size in bytes

0x09 - 0x18 Register Value Register contents

Table 7.3.15

Set Remote Register Reply

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x06 = Number of bytes in message following this byte

0x02 Packet Type 0x17 = SetRemoteRegisterReply

0x03 Status Error status: 0x00 = no error, 0xE1 = invalid argument

0x04 - 0x06 Originator MAC Address Originator’s MAC address, in Little Endian byte order

0x07 RSSI Packet RX power in dBm, -128 to 126, or 127 if invalid

Table 7.3.16

RxData event packet format details are shown in Figure Table 7.3.17:

RX Data Packet

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x00 to 0x6D = Number of bytes in message following this byte

0x02 Packet Type 0x26 = RxData event message

0x03 - 0x05 Originator MAC Address Originator’s MAC address, in Little Endian byte order

0x06 RSSI Packet RX power in dBm, -128 to 126, or 127 if invalid

0x07 - 0x73 Rx Data Up to 105 bytes of data from Base, up to 109 bytes from Router or Remote

Table 7.3.17

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Announce/Error message format details are shown in Tables 7.3.18 through 7.3.21:

Startup Announcement or Error Code

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x02 = Number of bytes in message following this byte

0x02 Packet Type 0x27 = Indicates this is an Announce/Error message

0x03 Announce Status

0xA0 = Startup initialization complete

0xA1 = Synchronized to fast beacon

0xE1 = Invalid argument

0xE4 = Register read only error

0xEC = Brownout reset

0xED = Watchdog reset

0xEE = Hardware Error (Crystal or Radio Error)

Table 7.3.18

Join Announcement

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x06 = Number of bytes in message following this byte

0x02 Packet Type 0x27 = Indicates this is an Announce/Error message

0x03 Announce Status 0xA3 = Joined network

0x04 Network ID ID of network that was joined

0x05 - 0x07 Parent MAC Address MAC address of parent, in Little Endian byte order

Table 7.3.19

Exit Announcement

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x03 = Number of bytes in message following this byte

0x02 Packet Type 0x27 = Indicates this is an Announce/Error message

0x03 Announce Status 0xA4 = Exited network

0x04 Network ID ID of network that was exited

Table 7.3.20

Heartbeat Announcement

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x0C = number of bytes in message following this byte

0x02 Packet Type 0x27 = Indicates this is an Announce/Error message

0x03 Announce Status 0xA8 = Heartbeat message

0x04 - 0x06 Device MAC Address MAC address of originator, in Little Endian byte order

0x07 - 0x09 Parent MAC Address MAC address of parent, in Little Endian byte order

0x0A Parent Network ID Network ID of device’s parent

0x0B Base Mode Network ID Network ID if device is a router, otherwise 0xFF

0x0C Beacon RX Power Average beacon RX power in dBm, uses 0.0625 “alpha” averaging filter,

-128 to 126 or 127 if invalid

0x0D Parent RX Power RX power of packet as received by device’s parent in dBm, -128 to 126 or

127 if invalid

Table 7.3.21

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RxEvent message format details are shown in Table 7.3.22:

RX Event Packet

Byte Offset Field Description

0x00 Start-of-Packet 0xFB = Indicates start of protocol formatted message

0x01 Length 0x12 = number of bytes in message following this byte

0x02 Packet Type 0x28 = RxEvent

0x03 - 0x05 Originator MAC Address Originator’s MAC address, in Little Endian byte order

0x06 RSSI Packet RX power in dBm (-128 to 127)

0x07 GPIO Readings Bit Field (GPIO0..GPIO5) indicating GPIO readings

0x08 - 0x09 ADC0 Reading ADC0 Reading, 0x0000 - 0x0FFF, in Little Endian byte order

0x0A - 0x0B ADC1 Reading ADC1 Reading, 0x0000 - 0x0FFF, in Little Endian byte order

0x0C - 0x0D ADC2 Reading ADC2 Reading, 0x0000 - 0x0FFF, in Little Endian byte order

0x0E - 0x0F Event Flags Bit Field Indicating which events have occurred:

Bit 0: GPIO0 Triggered

Bit 1: GPIO1 Triggered

Bit 2: GPIO2 Triggered

Bit 3: GPIO3 Triggered

Bit 4: Periodic Report Interval

Bit 5: ADC0 Threshold Triggered

Bit 6: ADC1 Threshold Triggered

Bit 7: ADC2 Threshold Triggered

Bits 8-15: Unused (0)

0x10 - 0x11 DAC0 Setting DAC0 setting, 0x0000 - 0x0FFF, in Little Endian byte order

0x12 - 0x13 DAC1 Setting DAC1 setting, 0x0000 - 0x0FFF, in Little Endian byte order

Table 7.3.22

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7.4 Configuration Parameter Registers

The configuration parameters in a DNT90 module are stored in a set of variable length registers. Most

registers are read-write, with a few read-only or write-only. Changes made to the register settings are

temporary until a MemorySave command is executed. Resetting or power-cycling the module will clear

any changes that have not been saved to permanent memory using the MemorySave command. DNT90

modules can be configured to start in protocol mode at power-up, in which case the EnterProtocolMode

command is not required.

7.4.1 Bank 0x00 - Transceiver Setup

Bank Location Name R/W Size Range Default

0x00 0x00 DeviceMode R/W 0x01 0..2 0 (remote)

0x00 0x01 HopDuration R/W 0x01 16..200 40 (20 ms)

0x00 0x02 ParentNwkID R/W 0x01 0..63, 255 255 (any parent)

0x00 0x03 SecurityKey R/W 0x10 0..2^128-1 0

0x00 0x13 SleepModeEn R/W 0x01 0..2 0 (off)

0x00 0x14 WakeResponseTime R/W 0x02 0..30000 500 (500 ms)

0x00 0x16 WakeLinkTimeout R/W 0x01 0..255 5 (5 s)

0x00 0x17 AltParentNwkID R/W 0x01 0..63, 255 255 (disabled)

0x00 0x18 TxPower R/W 0x01 0..1 1 (+22 dBm)

0x00 0x19 UserTag R/W 0x10 string “DNT90”

0x00 0x29 RmtTransDestAddr R/W 0x03 0x000000 (Base)

0x00 0x2C Store&ForwardEn R/W 0x01 0..1 0 (disabled)

0x00 0x2D BaseModeNetID R/W 0x01 1..63, 255 255

0x00 0x2E HeartbeatIntrvl R/W 0x02 0..65535 20 (seconds)

0x00 0x30 SystemId R/W 0x01 0..255 0

0x00 0x31 EndToEndAckEnable R/W 0x01 0..1 0 (disabled)

0x00 0x32 LinkRetryInterval R/W 0x02 0..65535 0 (disabled)

0x00 0x34 FastBeaconCount R/W 0x02 0..65535 0 (off)

0x00 0x36 FastBeaconTrig R/W 0x01 0..255 0 (off)

Table 7.4.1.1

DeviceMode - this parameter selects the operating mode for the radio:

0x00 = remote (default)

0x01 = base

0x02 = router (store and forward system)

Note that changing this setting does not take effect immediately. It must be followed by a MemorySave

command and then either a hardware reset or a power off/on cycle. A router without a valid BaseMode-

NetID operates as a remote.

HopDuration - this parameter sets the duration of the hop frame, and can only be set on the base. The

duration is an 8-bit value, 0.5 ms/count. The valid range is from 8 to 100 ms. Changing the hop duration

on the base must be followed by a MemorySave command to allow the change to persist through a reset

or power cycle. A HopDuration change takes effect immediately. Child radios will re-link following a

HopDuration parameter change as they receive the updated hop duration value from the base.

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ParentNwkID - this parameter specifies the parent (BaseModeNetID) that a child radio is allowed to join.

The valid range of this parameter is 0 to 63 (0x00 to 0x3F), plus 255 (0xFF). Setting the ParentNwkID to

255 allows connection to any parent. This parameter is applicable only to remotes and routers. Also see

the discussion of AltParentNwkID below.

Security Key - this 16-byte parameter sets the 128-bit AES encryption key. To protect the key, it is a write-

only parameter for the user. It always reads back as 0x2A.

SleepModeEn - this parameter enables/disables sleep mode (remotes only). Sleep mode is used in con-

junction with the automatic I/O reporting feature to wake up a remote on specific triggers. The default val-

ue for this parameter is 0 (off). Setting this parameter to 1 invokes sleep mode immediately. Setting this

parameter to 2 invokes sleep mode following reset, allowing this and other parameter updates to be

stored before sleep mode is invoked.

WakeResponseTime - this parameter set how long sleep is deferred in a DNT90 remote configured for

sleep mode after:

link acquisition

receiving an ACK from the device’s parent

receiving a packet that requires processing by the device

after receiving a protocol packet from the device’s local host.

WakeLinkTimeout - this parameter sets the maximum length of time that a remote in sleep mode will

spend trying to acquire a link to its parent before going back to sleep, from a minimum of 1 to 255 se-

conds in 1 second steps. If this value is set to 0, the remote will stay awake and continue trying to link to

its base indefinitely.

AltParentNwkID - this parameter specifies an alternate parent (BaseModeNetID) that a child radio is

allowed to join. This parameter is used to provide more robust message routing when setting the Parent-

NwkID to its 0xFF wildcard value is not appropriate. The valid range of this parameter is 0x00 to 0x3F,

plus 0xFF. Rather than specifying wildcard operation, setting the AltParentNwkID to 0xFF disables the

selection of an alternate parent. This parameter is applicable only to remotes and routers.

TxPower - this parameter sets the transmit power level (default is 0x01):

0x00 = +16 dBm or 40 mW

0x01 = +22 dBm or 158 mW

UserTag - this parameter is a user definable field intended for use as a location description or other iden-

tifying tag such as a “friendly name”.

RmtTransDestAddr - this parameter holds the default destination for transparent mode data packets and

event packets. This parameter defaults to the base station’s address (0x000000) except on a base sta-

tion, where at startup it will be changed to the broadcast address (0xFFFFFF) if the firmware detects that

it is set to 0x000000. Note - if a module’s configuration is changed from a base to a remote or router, this

parameter must be set back to 0x000000 or the module will send broadcast packets in transparent mode

or for event packets.

Store&ForwardEn - setting this parameter to 0x01 enables store-and-forward system operation. Store-

and-forward operation is disabled by default.

BaseModeNetID - applicable to the base and routers only, this parameter specifies the network ID of a

device’s own network when acting as parent. A child is allowed to join a network when its ParentNwkID

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parameter matches a parent’s BaseModeNetID. The valid range of this parameter is 0x00 to 0x3F. A val-

ue greater than 0x3F is invalid and will be forced to 0x00 on a base. A router with an invalid Base-

ModeNetID will be forced to operate as a remote.

HeartbeatInterval - When set to 0, all heartbeats are disabled, including the initial heartbeat issued after

link acquisition. When set to 0xFFFF (default), periodic heartbeats are disabled but the initial linkup

heartbeat is enabled. The periodic heartbeat interval is scaled 1 second/count, and applies to DNT90s

where sleep mode is disabled. Remotes with sleep mode enabled must have periodic reports and/or ADC

sampling enabled for heartbeats to be generated.

SystemId - this parameter holds the ID for a DTN90 system. DNT90 systems that may physically overlap

must have different system IDs.

EndToEndAckEnable - when this parameter is set to 1 and the DNT90 is in protocol mode, the originator

will indicate in its transmitted packet that an ACK is expected from the packet’s destination node. Setting

this parameter to 0x00 reduces network congestion in a store-and-forward system, but no TxDataReply

will be sent from the destination to confirm reception.

LinkRetryInterval - when a remote enters sleep mode with an unsent packet in its queue, the remote will

wake up after the number of seconds held in this parameter and try to link so that pending packets can be

transmitted. When this parameter is set to 0, this feature is disabled.

FastBeaconCount - this parameter controls the fast beacon mode, which is used to speed up network

synchronization. Fast beacon mode is especially useful for multi-level store-and-forward networks that are

configured with long hop durations. Fast beacon mode is controlled by the base station. If the Fast-

BeaconCount parameter is set to a non-zero value, when the base is reset, powered up or the Fast-

BeaconTrig parameter is set to a non-zero value, it will output the number of 6 ms beacons specified in

the FastBeaconCount parameter. The base and all of its children will synchronously decrement a version

of the parameter in their beacons, such that it will reach 0 simultaneously on all devices. This allows all

nodes in the DNT90 system to simultaneously transition to using the configured base slot size and num-

ber of slots. The beacons also inform all child devices that the network is in Fast beacon mode, so that all

children will observe the FastBeaconCount and assume, in addition to the 6ms hop timing, a base slot

size of 0 and a number of slots equal to 1. If the cycled base station operating parameters transmitted in

the beacons, including the BaseSlotSize and NumSlots (see Bank 0x01 parameters) are stable, then a

further speedup of synchronization can be achieved by setting the NumBaseParms on the base station to

8. However, this should be done only after all child devices are known to have configuration parameters

identical to the base station’s saved in their EEPROM. The first 9 parameters contain the AES counter

and MAC address that are needed to synchronize encryption, along with NumBaseParms.

FastBeaconTrig - when this parameter is set to any non-zero value on a base station, fast beacon mode

starts if the fastBeaconCount register is already set to a non-zero value. It auto-clears on a base station

and will read back as 0 after it is cleared. On a router or remote, it would do nothing and will not clear

except after reset.

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7.4.2 Bank 0x01 - System Settings

Bank 1 holds configuration parameters to be input to the base only. The base passes these parameters to

the routers and remotes as needed. The exception is InitFrequencyBand parameter which can also be set

in routers and remotes.

Bank Location Name R/W Size Range Default

0x01 0x00 InitFrequencyBand R/W 0x01 0..3, 255 0 (US)

0x01 0x01 NumSlots R/W 0x01 1..8 3

0x01 0x02 BaseSlotSize R/W 0x01 6..105 40

0x01 0x03 SlotLease R/W 0x01 1..255 2 (hops)

0x01 0x04 BcstAttemptLimit R/W 0x01 0..254 1

0x01 0x05 ArqAttemptLimit R/W 0x01 1..255 6

0x01 0x06 LinkDropThreshold R/W 0x01 1..255 10 (hops)

0x01 0x07 P2PReplyTimeout R/W 0x01 0..255 100 (hops)

0x01 0x08 RegistryTimeout R/W 0x01 0..255 50 (hops)

0x01 0x09 NumBaseParms R/W 0x01 8..21 21

Table 7.4.2.1

InitFrequencyBand - this parameter sets the range of frequencies and channel spacing over which the

DNT90 system will initially operate. Four bands are available:

0x00 Band 0: 902.76 to 927.24 MHz, 52 channels, 480 kHz spacing

0x01 Band 1: 902.76 to 926.76 MHz, 26 channels, 960 kHz spacing

0x02 Band 2: 915.72 to 927.74 MHz, 25 channels, 480 kHz spacing

0x03 Band 3: 902.76 to 914.76 MHz, 26 channels, 480 kHz spacing

0xFF wildcard - will accept any band

Bands 0, 1, 2 and 3 can be used in North and South America (902 to 928 MHz band), with Band 2 usable

in Australia.

NumSlots - this parameter sets the number of slots available for child transmissions following the parent’s

beacon transmission on a hop.

BaseSlotSize - this parameter set the maximum number of payload bytes that the base can send on a

single hop. The default value is 40 bytes.

SlotLease - this parameter set the number of hops a parent radio will reserve a slot for a child after re-

ceiving a message from that child. Small values such as 2 are suited to short data bursts, and larger val-

ues are generally a better choice when devices send a stream of non-continuous data across consecutive

hops. The minimum value is 1, assuring that a child can receive an ACK on the next hop after it transmits.

BcstAttemptLimit - setting this parameter to 0 enables automatic broadcast message repeats based on

the ArqAttemptLimit parameter value. Setting this parameter to a value between 1 and 254 specifies the

number of broadcast message repeats independent of the ArqAttemptLimit. This parameter should not be

set to 0 if ArqAttemptLimit is set to 255.

ArqAttemptLimit - this sets the maximum number of attempts that will be made to send a message on the

RF link. Setting this parameter to the maximum value of 255 is a flag value indicating that there should be

no limit to the number of attempts to send each packet (infinite number of attempts). This mode is intend-

ed for point-to-point networks in serial data cable replacement applications where absolutely no packets

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can be lost. Note - if this mode is used in a multipoint network, one remote that has lost link will shut down

the entire network if the base is trying to send it data.

LinkDropThreshold - this is the number of consecutive beacons missed by a remote that causes the re-

mote to restart a link acquisition search. Please contact RFM technical support before making changes to

the parameter.

P2PReplyTimeout - this parameter sets the reply timeout for peer-to-peer messages sent from one node

to another. Because each leg of the journey from one node to another and back may take multiple trans-

mit attempts, the length of time to confirm receipt and issue a TxDataReply is subject to more variation

than a transmission directly between a base and a remote. When AckEnable is selected, the P2PReply-

Timeout parameter specifies the maximum number of hops or hop pairs that a remote will wait for a reply

from its recipient. If a reply returns sooner than the timeout, the remote will send a TxDataReply indicating

success (ACK) to its host as soon as it is received, and cancels the timeout. If a reply does not come

back before the timeout expires, the remote will send a TxDataReply to its host indicating failure (NAK). If

a reply should come back after the timeout expires the remote will ignore it, as a TxDataReply has al-

ready been sent. The units of this parameter are in hops for point-to-point and point-to-multipoint opera-

tion and in hop pairs for store-and-forward operation.

RegistryTimeout - this parameter sets the number of hops without contact from a child device for which a

parent device will preserve the Transaction ID (TID) history for that child. The TID is used to filter out du-

plicate packets. After a registry timeout occurs, the TID history is discarded.

NumBaseParms - this parameter controls the number of cycled parameters sent in the base station bea-

con. It must be left in its default value of 21 until all nodes in a DNT90 system have received all cycled

parameters and stored them locally in EEPROM. At this point the number of cycled parameters can be

set to 9, which will significantly speed up future system resynchronizations.

7.4.3 Bank 0x02 - Status Parameters

Bank Location Name R/W Size Range Default

0x02 0x00 MacAddress R 0x03 0..0xFFFFFF Fixed value

0x02 0x03 CurrNwkID R 0x01 0..63, 255 Current Value

0x02 0x04 CurrFreqBand R 0x01 0..2, 255 Current Value

0x02 0x05 LinkStatus R 0x01 0..5 Current status

0x02 0x06 RemoteSlotSize R 0x01 0..109 Current Value

0x02 0x07 SlotNumber R 0x01 0..7 Current Value

0x02 0x08 HardwareVersion R 0x01 0x41..0x5A 0x43 = Rev “C”

0x02 0x09 FirmwareVersion R 0x01 0x00..0xFF Current FW load

0x02 0x0A FirmwareBuildNum R 0x02 0..65535 Current FW load

0x02 0x0C FirmwareBuildDate R 0x03 BCD (“YYMMDD”) Current FW load

0x02 0x0F FirmwareBuildTime R 0x03 BCD (“HHMMSS”) Current FW load

0x02 0x12 RssiIdle R 0x01 -128..127 Current Value

0x02 0x13 RssiLast R 0x01 -128..127 Current Value

0x02 0x14 AvgBeaconPower R 0x01 -128..127 Current Value

0x02 0x15 ParentMacAddress R 0x03 0..0xFFFFFF Current Value

0x02 0x18 ModelNumber R 1 0x90 indicates DNT90

Table 7.4.3.1

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MacAddress - this parameter holds the radio's unique 24-bit MAC address.

CurrNwkID - this parameter holds the ID of the network the radio is currently assigned to or connected to.

A value of 255 (0xFF) means the radio has powered up and is scanning for a network but has not yet

joined one.

CurrFreqBand - this parameter holds the frequency band of the network that the radio is currently as-

signed to or connected to. A value of 0xFF means the radio has powered up and is scanning for a net-

work but has not yet joined one.

LinkStatus - this parameter holds the link status of a router or remote:

0x00 = idle

0x01 = lost link

0x02 = acquiring link

0x03 = collecting parameters from the base

0x04 = registering

0x05 = registered

RemoteSlotSize - this parameter holds the current remote slot size, defined as the maximum number of

message bytes a remote can send on a single hop. The RemoteSlotSize is calculated by each radio in a

system based on the values of the HopDuration, BaseSlotSize, and NumSlots parameters.

SlotNumber - this parameter holds the current slot number assigned to a router or remote.

HarwareVersion - this parameter holds an identifier indicating the hardware revision (ASCII character). A

value of 0x43 is defined for the DNT90 Revision C hardware.

FirmwareVersion - this parameter holds the firmware version of the radio in 2-digit BCD format.

FirmwareBuildNum - this parameter holds the firmware build number, in binary format.

FirmwareBuildDate - this parameter holds the date of firmware build in MM/DD/YY format.

FirmwareBuildTime - this parameter holds the time of the firmware build in HH:MM:SS format.

RssiIdle - this 2’s compliment parameter holds the last RSSI measurement in dBm made during a time

when the RF channel was idle. This parameter is useful for detecting interferers.

RssiLast - this 2’s compliment parameter holds the last RSSI measurement in dBm made during the re-

ceipt of an RF packet with a valid CRC. This parameter is useful for network commissioning/diagnostics.

AvgBeaconPower - this 2’s compliment parameter holds the alpha-filtered beacon power (dBm) received

from a device’s parent, where alpha = 0.0625.

ParentMacAddress - this parameter holds the MAC address of a DNT90’s parent.

ModelNumber - this parameter specifies the DNT model, in this case a DNT90.

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7.4.4 Bank 0x03 - Serial and SPI Settings

Bank Location Name R/W Size Range Default

0x03 0x00 SerialRate R/W 0x01 0..10 3 (9600 baud)

0x03 0x01 SerialParams R/W 0x01 0..7 0 (8-N-1)

0x03 0x02 SpiMode R/W 0x01 0..2 0 (SPI disabled)

0x03 0x03 SpiRateSel R/W 0x01 0..2 0 (125 kHz)

0x03 0x04 SpiOptions R/W 0x01 0..7 0

0x03 0x05 SpiMasterCmdLen R/W 0x01 0..16 0

0x03 0x06 SpiMasterCmdStr R/W 0x10 0..16 byte string All 0x00 bytes

Table 7.4.4.1

SerialRate - this parameter sets the serial data rate as shown below:

Setting Serial rate

0x00 1.2 kbps

0x01 2.4 kbps

0x02 4.8 kbps

0x03 9.6 kbps

0x04 14.4 kbps

0x05 19.2 kbps

0x06 28.8 kbps

0x07 38.4 kbps

0x08 57.6 kbps

0x09 115.2 kbps

0x0A 230.4 kbps

0x0B 250.0 kbps

SerialParams - this parameter sets the serial mode options for parity and stop bits:

Setting Mode

0x00 No parity, 8 data bits, 1 stop bit (default)

0x01 No parity, 8 data bits, 2 stop bits

0x02 Reserved

0x03 Reserved

0x04 Even parity, 8 data bits, 1 stop bit

0x05 Even parity, 8 data bits, 2 stop bits

0x06 Odd parity, 8 data bits, 1 stop bit

0x07 Odd parity, 8 data bits, 2 stop bits

Note that 8-bit data with no parity is capable of carrying 7-bit data with parity for compatibility without loss

of generality for legacy applications that may require it.

SpiMode - this parameter sets the SPI operating mode:

Setting Mode

0x00 SPI disabled - serial UART mode (default)

0x01 SPI Slave mode

0x02 SPI Master mode

SpiRateSel - this parameter sets the SPI master mode clock rate:

Setting Mode

0x00 125 kbps

0x01 250 kbps

0x02 500 kbps

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SpiOptions - this parameter allows the SPI to be configured with the following options:

Setting Option

0x00 Leading edge rising, sample leading edge, MSBs sent first

0x01 Leading edge rising, sample falling edge, MSBs sent first

0x02 Leading edge falling, sample leading edge, MSBs sent first

0x03 Leading edge falling, sample falling edge, MSBs sent first

0x04 Leading edge rising, sample leading edge, LSBs sent first

0x05 Leading edge rising, sample falling edge, LSBs sent first

0x06 Leading edge falling, sample leading edge, LSBs sent first

0x07 Leading edge falling, sample falling edge, LSBs sent first

SpiMasterCmdLen - this parameter sets the length for the SPI master command string that will be used to

interrogate the slave peripheral, when SPI master mode is selected with periodic I/O reporting enabled.

SpiMasterCmdStr - this parameter holds the SPI master command string that is used to interrogate the

slave peripheral when SPI master mode is selected and periodic I/O reporting is enabled.

7.4.5 Bank 0x04 - Host Protocol Settings

Bank Location Name R/W Size Range Default

0x04 0x00 ProtocolMode R/W 0x01 0..1 0 (Transparent)

0x04 0x01 TxTimeout R/W 0x01 0..255 0 (No timeout)

0x04 0x02 MinPacketLength R/W 0x01 0..255 1 (byte)

0x04 0x03 TransPtToPtMode R/W 0x01 0..1 1 (Last RX)

0x04 0x04 MsgsPerHop R/W 0x01 1..8 8

Table 7.4.5.1

ProtocolMode - this parameter selects the host protocol mode. The default is 0x00, which is transparent

mode, meaning the radio conveys whatever characters that are sent to it transparently, without requiring

the host to understand or conform to the DNT90's built-in protocol. This setting is recommended for point-

to-point applications for legacy applications such as wire replacements where another serial protocol may

already exist. Setting this parameter to 0x01 enables the DNT90 protocol formatting. It is not necessary to

define the same protocol mode for all radios in a network. For example, it is frequently useful to configure

all the remotes for transparent mode and the base for protocol mode. Note that it is possible for the host

to switch the radio from transparent mode to protocol mode and back as required by transmitting an

EnterProtocolMode command.

TxTimeout - this parameter is used to group transparent data to be sent in a single transmission rather

than being split over two hops. Messages sent over two hops can have gaps in the received data stream

that can cause problems for the receiving application - for example, Modbus RTU. This parameter is the

transmit timeout used for determining message boundaries in transparent data mode. Parameter units

are in milliseconds. A message boundary is determined whenever a gap between consecutive characters

is equal to or greater than the TxTimeout value, or the number of bytes reaches the MinPacketLength.

Either condition will trigger a transmission. The default TxTimeout value is 0 ms which will have the radio

send whatever data is in its transmit buffer as soon as possible.

MinPacketLength - this parameter is similar to TxTimeout except it uses the number of bytes received

instead of the amount of time without receiving a byte. The default is one byte. A transmission is triggered

when either the number of bytes reaches MinPacketLength or a gap is detected between consecutive

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characters greater than TxTimeout. If this parameter is set larger than the applicable slot size, the slot

size overrides this parameter and a transmission is triggered when the slot size is filled.

TransPtToPtMode - when this parameter is set to 0x00, the destination address of transparent mode

packets will be the configured RemoteDestAddr. When set to 0x01, the address initializes to Remote-

DestAddr and then updates to the most recent RX packet processed.

MsgsPerHop - this parameter sets the maximum number of messages a DNT90 can send in each hop

frame. The default value is 8 messages, which is suitable for most applications. Setting MsgsPerHop to a

low value allows message flow rate to be controlled.

7.4.6 Bank 0x05 - I/O Parameters

Bank Location Name R/W Size Range In Bits Default

0x05 0x00 All-IO R/W 0x0D 104 N/A

0x05 0x0D Gpio0 R/W 0x01 1 0

0x05 0x0E Gpio1 R/W 0x01 1 0

0x05 0x0F Gpio2 R/W 0x01 1 0

0x05 0x10 Gpio3 R/W 0x01 1 0

0x05 0x11 Gpio4 R/W 0x01 1 0

0x05 0x12 Gpio5 R/W 0x01 1 0

0x05 0x13 Adc0 R 0x02 12 N/A

0x05 0x15 Adc1 R 0x02 12 N/A

0x05 0x17 Adc2 R 0x02 12 N/A

0x05 0x19 EventFlags R/W 0x02 16 N/A

0x05 0x1B Dac0 R/W 0x02 12 0

0x05 0x1D Dac1 R/W 0x02 12 0

Table 7.4.6.1

All-IO - this 13-byte parameter packs all the following parameters into a single value. Note that the infor-

mation in parameters GPIO0 through GPIO5 is compressed into a single byte to save space in the All-IO

parameter. When the ADC is operating in differential mode, the ADC1 to ADC0 differential reading is

stored in the ADC0 position, and the ADC2 to ADC0 differential reading is stored in the ADC1 position.

The ADC2 reading is not used in ADC differential mode and this position is set to 0.

Gpio0 through Gpio5 - if a pin is configured as an output, writing to its corresponding parameter to sets

the pin’s logic state. If a pin is configured as an input, writing to its corresponding parameter enables or

disables the pin’s internal pull-up. Reading these registers returns the current level detected on the corre-

sponding pins.

Adc0 through Adc2 - read-only parameters that return the current reading for the selected ADC channel

(Little-Endian byte order). When the ADC is operating in differential mode, the ADC1 to ADC0 differential

reading is stored in the ADC0 position, and the ADC2 to ADC0 differential reading is stored in the ADC1

position. The ADC2 reading is not used in ADC differential mode and this position is set to 0. Also, see

the discussion of the AdcSampleIntvl parameter below.

EventFlags - used with the automatic I/O reporting feature, this parameter indicates which I/O events

have been triggered since the last report (write 0x0000 to reset):

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bits 15..8 Reserved

bit 7 ADC2 high/low threshold excursion

bit 6 ADC1 high/low threshold excursion

bit 5 ADC0 high/low threshold excursion

bit 4 Periodic timer report

bit 2 GPIO2 edge transition

bit 1 GPIO1 edge transition

bit 0 GPIO0 edge transition

Dac0 through Dac1 - sets the DAC outputs. The range of this parameter is 0x0000 to 0x0FFF.

7.4.7 Bank 0x06 - I/O Settings

Bank Location Name R/W Size Range In Bits Default

0x06 0x00 GpioDir R/W 0x01 6 0x00 (All inputs)

0x06 0x01 GpioInit R/W 0x01 6 0x00 (All zeros)

0x06 0x02 GpioAlt R/W 0x01 6 0x00

0x06 0x03 GpioEdgeTrigger R/W 0x01 8 0x01

0x06 0x04 GpioSleepMode R/W 0x01 6 0x00 (Off)

0x06 0x05 GpioSleepDir R/W 0x01 6 0x00 (All inputs)

0x06 0x06 GpioSleepState R/W 0x01 6 0x00 (All zero)

0x06 0x07 Dac0Init R/W 0x02 12 0x0000

0x06 0x09 Dac1Init R/W 0x02 12 0x0000

0x06 0x0B AdcSampleIntvl R/W 0x04 32 0x0A (100 ms)

0x06 0x0F Adc0ThresholdLo R/W 0x02 12 0xF800

0x06 0x11 Adc0ThresholdHi R/W 0x02 12 0x07FF

0x06 0x13 Adc1ThresholdLo R/W 0x02 12 0xF800

0x06 0x15 Adc1ThresholdHi R/W 0x02 12 0x07FF

0x06 0x17 Adc2ThresholdLo R/W 0x02 12 0xF800

0x06 0x19 Adc2ThresholdHi R/W 0x02 12 0x07FF

0x06 0x1B IoReportTrigger R/W 0x01 8 0x01 (GPIO0)

0x06 0x1C IoReportInterval R/W 0x04 32 30000 (ms)

0x06 0x20 IoPreDelay R/W 0x01 8 8 (ms)

0x06 0x21 IoBindingEnable R/W 0x01 1 0 (Disabled)

0x06 0x22 DacReference R/W 0x01 2 0 (ADC_EXT_REF)

0x06 0x23 AdcReference R/W 0x01 2 0 (ADC_EXT_REF)

0x06 0x24 AdcAveSelect R/W 0x01 8 0x01

0x06 0x25 ExtAdcScaleFactor R/W 0x02 16 0x8000

0x06 0x27 ExtAdcOffset R/W 0x02 16 0x0000

0x06 0x29 ExtDacScaleFactor R/W 0x02 16 0x8000

0x06 0x2B ExtDacOffset R/W 0x02 16 0x0000

0x06 0x2D VccAdcScaleFactor R/W 0x02 16 0x8000

0x06 0x2F VccAdcOffset R/W 0x02 16 0x0000

0x06 0x31 VccDacScaleFactor R/W 0x02 16 0x8000

0x06 0x33 VccDacOffset R/W 0x02 16 0x0000

0x06 0x35 1VAdcScaleFactor R/W 0x02 16 0x8000

0x06 0x37 1VAdcOffset R/W 0x02 16 0x0000

0x06 0x39 1VDacScaleFactor R/W 0x02 16 0x8000

0x06 0x3B 1VDacOffset R/W 0x02 16 0x0000

0x06 0x3D AdcDiffMode R/W 0x01 8 0 (single-ended)

0x06 0x3E AdcGainCh0 R/W 0x01 8 0 (gain = 1)

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Bank Location Name R/W Size Range In Bits Default

0x06 0x3F AdcGainCh1 R/W 0x01 8 0 (gain = 1)

0x06 0x40 AdcDiffScaleFactorCh0 R/W 0x02 16 0x8000

0x06 0x42 AdcDiffOffsetCh0 R/W 0x02 16 0x0000

0x06 0x44 AdcDiffScaleFactorCh1 R/W 0x02 16 0x8000

0x06 0x46 AdcDiffOffsetCh1 R/W 0x02 16 0x0000

0x06 0x47 FastAdcPrescaler R/W 0x01 1 byte, range 1..7 5 (128)

0x06 0x48 SlowAdcPresccaler R/W 0x01 1 byte, range 0..7 2 (16)

0x06 0x49 MaxQueuedEvents R/W 0x01 1 byte, range 0..20 8 (reports)

0x06 0x4A AdcSkipCount R/W 0x01 1 byte 0 (samples)

Table 7.4.7.1

GpioDir - this parameter is a bitmask that sets whether each GPIO is an input (0) or outputs (1). The de-

fault is all inputs.

GpioInit - this parameter is a bitmask that sets the initial value for any GPIOs which are enabled as out-

puts. For GPIOs enabled as inputs, this sets the initial pull-up setting.

GpioAlt - Specifies which GPIO pins will have their alternate functions enabled: Bit 2 - diversity toggle en-

able, Bit 3 - RS485 enable, Bit 4 - /HOST_CTS enable, Bit5 - /HOST_RTS enable.

Bit Alternate Function Default Bit Mask

0 (none) 0 0x01

1 (none) 0 0x02

2 Diversity Toggle 0 0x04

3 RS485 (N/A in SPI Slave mode) 0 0x08

4 /Host_CTS (N/A in SPI Slave mode) 1 0x10

5 /HOST_RTS (N/A in SPI Slave mode) 1 0x20

Table 7.4.7.2

GpioEdgeTrigger -This parameter consists of a set of four 2-bit fields that define when GPIO triggers are

enabled for I/O event reporting:

bits 7..6 GPIO3 edge function

bits 5..4 GPIO2 edge function

bits 3..2 GPIO1 edge function

bits 1..0 GPIO0 edge function

The bit values for each GPIO map to the following settings:

Value GPIO edge behavior

11 Rising edge trigger, neither level keeps remote awake

10 Bidirectional edge trigger, neither level keeps remote awake

01 Rising edge trigger, holding high keeps remote awake

00 Falling edge trigger, holding low keeps remote awake

Table 7.4.7.3

GpioSleepMode - this parameter is a bitmask that enables configuring the I/O direction and state of

GPIO0..GPIO5 when the module is sleeping. Bits 0..5 correspond to GPIO0..GPIO5. Setting a Gpio-

SleepMode bit to 1 enables sleep mode configuration of the corresponding GPIO. Setting a GpioSleep-

Mode bit to 0 causes the corresponding GPIO to remain configured as in active mode. Note that when the

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GpioAlt bit is set for GPIO4, the corresponding GpioSleepMode bit is ignored and GPIO4 is controlled

directly by the GpioSleepState parameter bit 7.

GpioSleepDir - when GpioSleepMode is enabled, this parameter functions to set the direction of the

GPIOs during a device’s sleep period. This enables the user to provide alternate configurations during

sleep that will help minimize current consumption. Bits 0..5 correspond to GPIO0..GPIO5. Setting a

GpioSleepDir bit to 1 to specifies an output; 0 specifies an input.

GpioSleepState - when GpioSleepMode is enabled, this parameter functions as a bitmask to control the

states of the GPIOs, the RADIO_TXD output, and the /HOST_CTS and /DCD outputs during a device’s

sleep period. This allows the user to set alternate configurations during sleep to minimize current con-

sumption. Bits 0..5 correspond to GPIO0..GPIO5 respectively. Bit 6 sets the state of RADIO_TXD, and bit

7 sets the states of /HOST_CTS and /DCD. A sleep state bit is set to 1 to specify a high output or an in-

ternal pull-up on an input, or to 0 to specify a low output or no internal pull-up on an input. Bit 6 must be

set low in order to achieve minimum sleep current (high impedance load assumed), and the other bits

may need to be set low or high depending on their external loads. When bit 6 is set low, expect a serial

“break” condition to occur as the module wakes from sleep. The serial break condition can be eliminated

by setting bit 6 high, but sleep current will be increased.

Dac0Init - this parameter sets the initial value for DAC0 at startup.

Dac1Init - this parameter sets the initial value for DAC1 at startup.

AdcSampleIntvl - this parameter sets the frequency (sample interval) of ADC measurements used to de-

termine if a threshold has been exceeded or in calculating an average measurement value. The ADC

channels are read on each ADC cycle, along with the states of GPIO2 and GPIO3. Each AdcSampleIntvl

count equals 10 ms. The default is 100 ms. This interval will be the worst-case latency for ADC generated

interrupts. Note that AdcSampleIntvl is independent of IoReportInterval as the ADCs are read on both

intervals.

Adc0..2ThresholdLo/Hi - these parameters set the thresholds to trigger an I/O report based on ADC

measurements. If I/O reporting is enabled, a single event report containing the contents of the I/O bank is

generated when a threshold is crossed. Reporting is edge-triggered with respect to threshold boundaries,

not level-triggered. Additional reports are not triggered unless the ADC measurement first returns inside

the threshold boundary and then crosses the threshold again. Triggers occur whenever one of the follow-

ing inequalities is satisfied:

ADCx < ADCx_ThresholdLo

ADCx > ADCx_ThresholdHi

IoReportTrigger - a trigger event on any enabled trigger source will cause a DNT90 router or remote to

send an event message to the base containing the entire current values of the Bank 5.

bit 7 ADC2 high/low thresholds

bit 6 ADC1 high/low thresholds

bit 5 ADC0 high/low thresholds

bit 4 Periodic timer

bit 3 GPIO3 edge

bit 2 GPIO2 edge

bit 1 GPIO1 edge

bit 0 GPIO0 edge

I/O reporting is supported for remotes and routers only, not the base.

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IoReportInterval - when periodic timer I/O reporting is enabled, this parameter sets the interval between

reports. The parameter scaling is 10 ms/count, and the default report interval is every 30 seconds.

IoPreDelay - this parameter sets the time in milliseconds to delay collection of ADC readings after a mod-

ule wakeup event occurs, to allow settling of ADC input voltages.

IoBindingEnable - this parameter enables I/O binding. Setting this parameter to 0x00 disables I/O binding

(I/O mirroring) from a remote device. Setting this parameter 0x01 enables I/O mirroring. When enabled,

the data from any received event report is used to drive the device’s own outputs. GPIO2 will be set to the

event report’s GPIO0 reading, GPIO3 will be set to the event report’s GPIO1 reading, and DAC0 and

DAC1 will be set with the ADC0 and ADC1 readings respectively. Note that if the AdcDiffMode parameter

is set to 1, I/O binding cannot be used.

DacReference - this parameter selects the reference voltage for the DACs:

Setting Reference

0x00 ADC_EXT_REF

0x01 AVVC (Analog Vcc)

0x02 Reserved

0x03 Disable DAC operation

AdcReference - this parameter selects the reference voltage for the ADCs:

Setting Reference

0x00 ADC_EXT_REF

0x01 Internal Vcc divided by 1.6

0x02 Reserved

0x03 Disable ADC operation

AdcAveSelect - this parameter selects the number of ADC measurements to average to produce each

ADC reading, from 1 to 255 samples. Averaging over a larger number of measurements increases noise

filtering but also increases the time it takes to generate a set of readings:

ADC Mode Module Awake Module Sleeping

Single-ended, reading all three channels 216 µs 381 µs

Differential, reading both channels 160 µs 273 µs

Table 7.4.7.4

ExtAdcScaleFactor - this parameter is the scale factor applied to an ADC measurement when the ADC

reference is an external voltage. The scale factor parameter is multiplied by 32768. for example, the pa-

rameter value for a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

ExtAdcOffset - this parameter is the 2’s complement offset added to the scaled ADC measurement when

the ADC reference is an external voltage.

ExtDacScaleFactor - this parameter is the scale factor applied to a DAC measurement when the DAC

reference is an external voltage. The scale factor parameter is multiplied by 32768. for example, the pa-

rameter value for a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

ExtDacOffset - this parameter is 2’s complement the offset added to the scaled DAC measurement when

the DAC reference is an external voltage.

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VccAdcScaleFactor - this parameter is the scale factor applied to an ADC measurement when the ADC

reference is Vcc/1.6. The scale factor parameter is multiplied by 32768. for example, the parameter value

for a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

VccAdcOffset - this parameter is the 2’s complement offset added to the scaled ADC measurement when

the ADC reference is derived from Vcc/1.6.

VccDacScaleFactor - this parameter is the scale factor applied to a DAC measurement when the DAC

reference is Vcc. The scale factor parameter is multiplied by 32768. for example, the parameter value for

a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

VccDacOffset - this parameter is the 2’s complement offset added to the scaled DAC measurement when

the DAC reference is Vcc.

1VAdcScaleFactor - this parameter is the scale factor applied to an ADC measurement when the ADC

reference is the 1 V internal reference. The scale factor parameter is multiplied by 32768. for example,

the parameter value for a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

1VAdcOffset - this parameter is the 2’s complement offset added to the scaled ADC measurement when

the ADC reference is the 1 V internal reference.

1VDacScaleFactor - this parameter is the scale factor applied to a DAC measurement when the DAC ref-

erence is the 1 V internal reference. The scale factor parameter is multiplied by 32768. for example, the

parameter value for a scale factor of 1.12 = 1.12 * 32768 = 36700.16 or 0x8F5C.

1VDacOffset - this parameter is the 2’s complement offset added to the scaled DAC measurement when

the DAC reference is the 1 V internal reference.

AdcDiffMode - a parameter value of 0 selects single-ended ADC mode. In this mode, negative sensor

inputs are connected to ground and positive sensor inputs to ADC0, ADC1 and ADC2 respectively. Three

ADC measurements are made in this mode with a range of 0x0000 to 0x07FF. A parameter value of 1

selects signed differential mode with gain. In this mode, the negative sensor inputs are connected to

ADC0 and the positive inputs are connected to ADC1 and ADC2. Two ADC measurements are made in

this mode, ADC1 to ADC0 and ADC2 to ADC0, with a range (signed) from 0xF800 to 0x07FF. In differen-

tial mode, the AdcGainCh0 and AdcGainCh1 parameters can change the selected gain for the two ADC

readings, and the AdcDiff scale factors and offsets, both supplied by the customer, are used.

AdcGainCh0 - this parameter sets the preamplifier gain applied when making a differential measurement

of ADC1 relative to ADC0. Setting this parameter to 0x00 sets the gain to 1, 0x01 sets the gain to 2, 0x02

sets the gain to 4 and so on, up to 0x06 which sets the gain to 64. Note that the preamplifier output volt-

age saturates at 2.4 V regardless of the gain setting.

AdcGainCh1 - this parameter sets the gain applied when making a differential measurement of ADC2

relative to ADC0. Setting this parameter to 0x00 sets the gain to 1, 0x01 sets the gain to 2, 0x02 sets the

gain to 4 and so on, up to 0x06 which sets the gain to 64. Note that the preamplifier output voltage satu-

rates at 2.4 V regardless of the gain setting.

AdcDiffScaleFactorCh0/1 and AdcDiffOffsetCh0/1 - these parameters are applied to the raw ADC read-

ings in differential mode. These values are not factory calibrated, but can be calibrated by the user.

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FastAdcPrescaler - this parameter is the system clock divisor used to generate the ADC clock when the

system is being clocked at 16 MHz. Default value is 0x05 (system clock 128). Higher values corre-

spond to slower ADC clock rates. For example, 0x07 = 512, and 0x00 = 4. Note that larger prescalers

will increase the amount of time it takes to collect all readings. DIV4 is not valid when running at 16 MHz

because the maximum ADC clock rate is 2 MHz, so DIV8 is the lowest allowed.

SlowAdcPrescaler - System clock divisor used to generate the ADC clock when the system is being

clocked at 2 MHz, when exiting sleep mode. Default value is 0x02 (system clock 16). Higher values cor-

respond to slower ADC clock rates. For example, 0x07 = DIV512, and 0x00 = DIV4.

MaxQueuedEvents - this parameter sets the maximum number of Event Reports that can be queued at

one time by a DNT90. This parameter is used to prevent a router device from clogging up its outbound

queue with its own pending transmissions if it has having trouble obtaining link or an available slot from its

parent. This parameter defaults to 8, with a maximum value of 20.

AdcSkipCount - this parameter sets the number of measurements to skip (discard) when switching to a

new ADC channel. The skipped measurements allow transients in the ADC sample-and-hold circuit to

settle out. This parameter must be set to at least 0x03 when AdcDiffMode is selected. Note that the

IoPreDelay parameter discussed above provides a delay to allow signals external to the DNT90 to settle

following a wake up event, while AdcSkipCount skips measurements that may be distorted because the

internal voltage on the ADC sample-and-hold has not settled.

7.4.8 Bank 0xFF - Special Functions

Bank Location Name R/W Size Range Default

0xFF 0x00 UcReset W 0x01 0..2 N/A

0xFF 0x01 MemorySave W 0x01 0xD0..0xD2 N/A

0xFF 0x04 DiagSerialRate R/W 0x01 0..10 7 (38400 kbps)

0xFF 0x0C ForceDiscover W 0x03 (See Text) N/A

0xFF 0x10 DiagPortEn R/W 0x01 0..1 0 (disabled)

Table 7.4.8.1

UcReset - writing a 0 to this parameter initiates a full reset, writing 1 to initiates a reset to the serial boot-

loader, or writing a 2 to initiates a reset to the OTA bootloader client.

MemorySave - writing 0xD0 to this parameter load default values, writing 0xD1 saves settings to

EEPROM, or writing 0xD2 to save settings to EEPROM and resets the module.

DiagSerialRate - this parameter sets the diagnostic port serial data rate as shown below:

Setting Serial rate

0x00 1.2 kbps

0x01 2.4 kbps

0x02 4.8 kbps

0x03 9.6 kbps

0x04 14.4 kbps

0x05 19.2 kbps

0x06 28.8 kbps

0x07 38.4 kbps (default)

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0x08 57.6 kbps

0x09 115.2 kbps

0x0A 230.4 kbps

0x0B 250.0 kbps

ForceDiscoverRegister - a write to this register, typically using a broadcasted Set Remote Register com-

mand, will force a heartbeat reply if a device's parent has the specified base-mode network ID (or 0xFF

wildcard), and the least significant byte of the device’s MAC address is within a specified min/max range.

The payload consists of 3 bytes: NWKID (NN), minimum MAC address (LL), and maximum MAC address

(XX). In Little Endian hexadecimal format this would appear as “XXLLNN”.

DiagPortEn - setting this parameter to 0x01 enables diagnostic port operation.

7.5 Protocol-formatted Message Examples

7.5.1 Data Message

In this example, the ASCII text “Hello” is sent from the base to a remote using the TxData command.

The MAC address of the remote is 0x123456. The protocol formatting for the host message is:

SOP Length PktType Lo MAC MAC Hi MAC “H” “e” “l” “l” “o”

0xFB 0x09 0x05 0x56 0x34 0x12 0x48 0x65 0x6C 0x6C 0x6F

There are 9 bytes following the length byte, so the length byte is set to 0x09. Note that the 0x123456

network address is entered in Little-Endian byte order, 56 34 12. When an ACK to this message is re-

ceived from the remote, the base outputs a TxDataReply message to its host:

SOP Length PktType Lo MAC MAC Hi MAC Status RSSI

0xFB 0x07 0x15 0x56 0x34 0x12 0x00 0xB0

The 0x00 TxStatus byte value indicates the ACK reception from the remote. The RSSI value of the re-

ceived ACK is 0xB0, indicating a received signal strength of approximately -80 dBm .

The ASCII “Hello” message is output at the remote as an 0x26 RxData event. The address field contains

the originator’s address, 0x00 0x00 0x00, which is the base. The RSSI value of the received message is

0xB4, indicating a received signal strength of approximately -76 dBm. The data following the RSSI value

is the “Hello” text.

SOP Length PktType Lo MAC MAC Hi MAC RSSI “H” “e” “l” “l” “o”

0xFB 0x0A 0x26 0x00 0x00 0x00 0x35 0x48 0x65 0x6C 0x6C 0x6F

Note that if the remote was in transparent mode, only the “Hello” text would be output.

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7.5.2 Configuration Messages

In this example, the remote with MAC address 0x123456 is configured by the base (MAC address

0x000000) to generate RxEvent messages every 10 seconds. To do this, the IoReportInterval in the re-

mote is set to 10 seconds and the periodic report timer bit in the IoReportTrigger parameter is set ON.

The IoReportInterval and the IoReportTrigger parameters are loaded using SetRemoteRegister com-

mands. The command to set the IoReportInterval to 10 seconds is:

SOP Length PktType Lo MAC MAC Hi MAC Reg Bank Size Lo Val Val Val Hi Val

0xFB 0x0B 0x07 0x56 0x34 0x12 0x1C 0x06 0x04 0x10 0x27 0x00 0x00

The IoReportInterval parameter starts in location 0x1C of Bank 6. The report interval scaling is

1 ms/count, so a 10 second report interval is 10,000 units or 0x00002710 (Little-Endian format 10 27 00

00). The IoReportInterval parameter is updated and SetRemoteRegisterReply is returned:

SOP Length PktType Status Lo MAC MAC Hi MAC RSSI

0xFB 0x06 0x17 0x00 0x00 0x00 0x00 0xB2

The command to set the periodic report timer bit in IoReportTrigger is:

SOP Length PktType Lo Mac MAC Hi MAC Reg Bank Size Val

0xFB 0x08 0x07 0x56 0x34 0x12 0x1B 0x06 0x01 0x10

The IoReportTrigger parameter is in location 0x1B of Bank 6. The periodic report timer bit in IoReport-

Trigger is located in bit position four (00010000b) or 0x10. The IoReportTrigger parameter is updated and

SetRemoteRegisterReply is returned:

SOP Length PktType Status Lo MAC MAC Hi MAC RSSI

0xFB 0x06 0x17 0x00 0x00 0x00 0x00 0xB4

7.5.3 Sensor Message

In this example, the base host requests an ADC1 reading from a remote using the GetRemoteRegister

command, type 0x06. The MAC address of the remote is 0x123456. The current ADC1 measurement

parameter is read starting at register location 0x15 and Bank 5. The ADC reading spans two bytes. The

protocol formatting for this command is:

SOP Length PktType Lo Mac MAC Hi MAC Reg Bank Size

0xFB 0x07 0x06 0x56 0x34 0x12 0x15 0x05 0x02

Note the remote MAC address is entered in Little-Endian byte order, 56 34 12.

The ADC reading is returned in a GetRemoteRegisterReply message:

SOP Length PktType Status Lo MAC MAC Hi MAC RSSI Reg Bank Size Lo Val Hi Val

0xFB 0x0B 0x16 0x00 0x00 0x00 0x00 0xB7 0x1C 0x06 0x02 0x7B 0x08

Substantial information is returned in the message. The last two byes of the message give the ADC read-

ing in Little-Endian format, 7B 08. The ADC reading is thus 0x087B (2171). The RSSI value is the byte

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following the address, 0xB7 (-73 dBm). The TxStatus byte to the right of the GetRemoteRegisterReply

Packet Type is 0x00, showing the packet was acknowledged on the RF channel.

7.5.4 Event Message

The configuration example shown in Section 7.5.2 above causes the remote with MAC address 0x123456

to start sending event messages every 10 seconds as shown in the log below:

FB 12 28 56 34 12 B8 00 7A 01 36 01 FF 01 10 00 20 01 40 01

FB 12 28 56 34 12 B0 00 79 01 35 01 C0 01 10 00 20 01 40 01

FB 12 28 56 34 12 A9 00 72 01 35 01 D3 01 10 00 20 01 40 01

FB 12 28 56 34 12 AC 00 75 01 36 01 E7 01 10 00 20 01 40 01

The first received message in the above log is constructed as follows:

SOP Length PktType Addr Addr Addr RSSI Data

0xFB 0x12 0x28 0x56 0x34 0x12 B8

GPIO ADC0 ADC1 ADC2 Event Flags DAC0 DAC1

0x00 0x7A 0x01 0x36 0x01 FF 0x01 0x10 0x00 0x20 0x01 0x40 0x01

RxEvent messages are PktType 0x28. The message payload consists of the states of GPIO0 through

GPIO5, the input voltages measured by ADC0 through ADC2, the event trigger(s), and the DAC output

settings. Note the ADC readings, event flags and DAC settings are presented in Little-Endian order. The

remote is assumed to be always ON in this example. If the remote is placed in periodic sleep mode

(SleepMode = 1), a suitable value of the WakeResponseTime parameter should be set to allow the base

application to analyze the I/O report and send back a command to the remote as needed.

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8.0 DNT90DK/DNT90ADK Developer’s Kits

Figure 8.0.1 shows the main contents of a DNT90DK Developer’s kit:

Figure 8.0.1

8.1 Kit Contents

 DNT90DK - two DNT90P radios installed in DNT90 interface boards, labeled Base and Remote

 DNT90DK - two 2 dBi dipole antennas with two MMCX-to-RSMA coaxial adaptor cables

 DNT90ADK - 2 DNT90PA radios installed in DNT90 interface boards, labeled Base and Remote

 All Kits - 2 wall-plug power suppliers, 9 VDC, 120/240 VAC, plus 2 batteries, 9 VDC (not show

above)

 All Kits - 2 RJ-45/DB-9F cable assemblies and two A/B USB cables

 All Kits - 1 DNT90DK/DNT90ADK documentation and software CD

8.2 Additional Items Needed

To operate the kit, the following additional item is needed:

 One PC with Microsoft Windows XP, Vista or Windows 7 operating system. The PC must be

equipped with a USB port or a serial port capable of operation at 9600 bps.

8.3 Developer’s Kit Default Operating Configuration

The default operating configuration of the DNT90DK developer’s kit is point-to-point with transparent seri-

al data at 9600 bps, 8N1. One DNT90P is preconfigured as a base and the other as a remote. Labels on

the bottom of the interface boards specify Base or Remote. The defaults can be overridden to test other

operating configurations using the DNT90 Demo utility discussed in Section 8.5.

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8.4 Developer’s Kit Hardware Assembly

Observe ESD precautions when handling the kit circuit boards. When shipped, the DNT90P radios and

U.FL coax jumper cables are installed in the interface boards, as shown in Figure 8.4.1. If a DNT90P ra-

dio and/or the U.FL jumper cable has been unplugged after receipt, confirm the DNT90P is correctly

plugged into its interface board with the radio oriented so that its U.FL connector is next to the U.FL con-

nector on the interface board, as shown in Figure 8.4.2. Also check the radio’s alignment in the socket on

the interface board. No pins should be hanging out over the ends of the connector. Next, screw each di-

pole antenna into and adaptor cable and “snap” the other end of the adaptor cable into the MMCX RF

connector on the development board as shown in Figure 8.4.2. Note that no external antenna is required

when using the DNT90PA radios supplied in the DNT90A Kits.

Figure 8.4.1 Figure 8.4.2

As shown in Figure 8.4.3, confirm there is a jumper on J10 (this jumper can be removed later and a cur-

rent meter connected across J10 to measure just the DNT90’s current consumption during operation).

J P 1 0

Figure 8.4.3

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There are three serial connectors and a power connector on the end of each interface board, as shown in

Figure 8.4.4. The RJ-45 connector provides an RS232 interface to the DNT90P’s main serial port. The

USB connector provides an optional interface to the radio’s main serial port. The RJ-11 connector pro-

vides an RS232 interface to the radio’s optional diagnostic port. The DNT90 Demo utility program runs on

the radio’s main port.

Figure 8.4.4

Many desktop PCs have a built-in serial port capable of operation at 9600 bps. The kit can be run satis-

factorily at the 9600 bps data rate, but not at its fastest throughput. Use the RJ-45 to DB-9F cable as-

semblies for serial port operation.

Optionally, the kit development boards can be run from USB ports. Plugging in the USB cable automati-

cally switches operation from the RJ-45 connector. The USB interface is based on an FT232RL serial-to-

USB converter IC manufactured by FTDI. The FT232RL driver files are located in the i386 and AMD64

folders on the kit CD, and the latest version of the drivers can downloaded from the FTDI website,

www.ftdichip.com. The drivers create a virtual COM port on the PC. Power the Base using one of the

supplied wall-plug power supplies. Next connect the Base to the PC with a USB cable. The PC will find

the new USB hardware and open a driver installation dialog box. Enter the letter of the drive holding the

kit CD and click Continue. The installation dialog will run twice to complete the FT232R driver installation.

8.5 DNT90 Utility Program

The DNT90 utility program requires only one PC for initial kit operation and sensor applications (ADC,

DAC and digital I/O). Two serial/USB ports are required for bidirectional serial communications. Section

8.6 below covers using the DNT90 Demo utility program for initial kit operation and familiarization. Section

8.6.1 covers serial message communication and radio configuration.

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8.6 Initial Kit Operation

Create a file folder on the PC and copy the contents of the kit CD into the folder.

Connect the Base to the PC and power up the Base using a wall-plug power supply.

The DNT90 Demo utility program is located in the PC Programs folder. The DNT90 Demo utility program

requires no installation and can be simply copied to the PC and run. Start the utility program on the PC.

The start-up window is shown in Figure 8.6.1.

Figure 8.6.1

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Click on Connect to open the Select Comm Port Settings dialog box, as shown in Figure 8.6.2. If

necessary, set the baud rate to 9600 bps. Set the CommPort to match the serial port connected to the

Base, either the hardware port or the USB virtual serial port. Then click OK to activate the serial

connection.

Figure 8.6.2

At this point the utility program will collect data from the Base, filling in the Local Radio column as shown

in Figure 8.6.3. Next power up the Remote using a wall-plug power supply. The Remote will transmit a

“heartbeat” message on power up as shown in the Status Window. Click on the drop-down box at the top

of the Radio 1 column and load the MAC Address for the Remote from the heartbeat message. Next

press the Start button using the default 1 second Refresh Delay.

Figure 8.6.3

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The utility program will display updated data on the Remote in the Radio 1 column, including bar graphs

of RSSI signal strength in dBm and percent packet success rate, as shown in Figure 8.6.4. Adjusting the

large pot on the Remote can be observed on the Potentiometer (ADC0) row.

Figure 8.6.4

Note: If the Remote is powered up before the DNT90 Demo program is running and connected to the

Base, the initial Remote heartbeat will be missed and it will be necessary to manually enter the Remote’s

MAC address in the MAC Address field under Radio 1 and then press the Enter key to display the Re-

mote information.

If any difficulty is encountered in setting up the DNT90DK development kit, contact RFM’s module tech-

nical support group. The phone number is +1.678.684.2000. Phone support is available from 8:30 AM to

5:30 PM US Eastern Time Zone, Monday through Friday. The E-mail address is tech_sup@rfm.com.

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8.6.1 Serial Communication and Radio Configuration

Connect PCs to both the Base and the Remote for serial communication testing (alternately one PC can

be used with two serial ports and two instances of the DNT90 Demo program running). Click the Stop

button under the Refresh Delay label on the I/O Tools tab and move to the Transmit Tools tab, as shown

in Figure 8.6.1.1.

Figure 8.6.1.1

Pressing the Transmit button on this screen sends the message in the Data to Transmit text box to the

selected MAC Address. Note that the MAC address a remote uses for the base is 0x000000. Data sent to

the local radio is displayed in the Received Data text box. Received data can be displayed as ASCII

(default) or in Hexadecimal format by checking the Hex Mode check box. When the Transmit Interval is

set to zero, Data to Transmit is sent once when the Transmit button is clicked. When the Transmit Interval

is set to a positive number, Pressing the Transmit button once will cause a transmission each transmit

interval (seconds) until the button is pressed again.

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Returning to the I/O Tools tab, the multi-tab Configuration window for each radio can be accessed by

clicking on its Config button. The data presented on the first six tabs corresponds to configuration register

Banks 0 through 5 as discussed in Section 4.2 above, with the data on the next two tabs corresponding to

configuration register Bank 6.

Figure 8.6.1.2

The Transceiver Setup Tab is shown in Figure 8.6.1.2 and corresponds to Bank 0. The current values of

each Bank 0 parameter are displayed and can be updated by selecting from the drop-down menus or

entering data from the keyboard, and then pressing the Apply Changes button. Note that data is

displayed and entered in Big-Endian order. The utility program automatically reorders multi-byte data to

and from Little-Endian order when building or interpreting messages.

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Figure 8.6.1.3

Figure 8.6.1.3 shows the System tab contents, corresponding to Bank 1. The current values of each pa-

rameter are displayed and can be updated by selecting from the drop-down menu or entering data from

the keyboard, and then pressing the Apply Changes button. Note that Bank 1 holds configuration parame-

ters for the base only except for Broadcast Mode, which applies to both the base and the remotes.

Figure 8.6.1.4

Figure 8.6.1.5 shows the Status tab contents, corresponding to Bank 2. Note the Status tab contains

read-only parameters.

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Figure 8.6.1.5

Figure 8.6.1.5 shows the Serial tab contents corresponding to the serial parameters in Bank 3. The val-

ues shown are the defaults for serial port operation.

Figure 8.6.1.6

Figure 8.6.1.6 shows the Protocol tab contents, corresponding to Bank 4. Transparent serial data com-

munication is currently chosen.

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Figure 8.6.1.7

Figure 8.6.1.7 shows the I/O Parameters tab contents, corresponding to Bank 5. All GPIO ports are con-

figured as inputs. The 12-bit ADC input readings and DAC output settings are given in Big-Endian byte

order. Event flags are presented on the right side of the window.

Figure 8.6.1.8

Figure 8.6.1.8 shows the first I/O Settings tab contents, corresponding to Bank 6 GPIO configurations

other than alternate GPIO functions. This tab allows the direction of the GPIO ports to be set both for ac-

tive and sleep modes, and in the case of GPIO outputs, the initial power up states and sleep mode states

to be set. When GPIO ports 0 - 3 are configured as inputs, event interrupts can be set for them with check

boxes. The type of interrupt trigger is selected from the drop-down boxes to the right of the check boxes.

Periodic I/O reporting, reporting interval and enable/disable sleep I/O states and I/O binding can also be

configured under this tab.

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Figure 8.6.1.9

Figure 8.6.1.9 shows the second I/O Setup tab contents, corresponding to Bank 6 ADC input and DAC

output parameters. The ADC and DAC reference voltages, the ADC sampling interval, the high and low

ADC thresholds for event reporting and event reporting triggers on each ADC channel can be set, along

with the initial output values for each DAC channel. The event reporting I/O predelay and alternate GPIO

functions can also be set from this tab.

The DNT90 Demo Utility File, Options and Help menus are shown in Figure 8.7.8.

Figure 8.7.8

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8.7 DNT90 Interface Board Features

The locations of the LEDs on the interface board that are used by the DNT90 are shown in Figure 8.8.1.

Figure 8.8.1

DCD LED, D11, illuminates on a router or remote to indicate it is registered with its parent and can partic-

ipate in RF communications. The DCD LED illuminates on the base when one or more routers or remotes

are registered to it, unless the base has been configured to assert DCD on power up. In this case it will be

on as long as the development board is powered. Activity LED, D10, illuminates when transmitting or re-

ceiving RF data. Power LED, D1, illuminates with the DNT90 and its interface board are powered. GPIO2

LED, D5, and GPIO3 LED, D4, can be controlled by configuring GPIO2 and GPIO3 as outputs on the

DNT90. These LEDs are illuminated with a logic high signal.

Figure 8.8.2

Figure 8.8.2 shows the connectors and switches to the right of the DNT90P mounting socket. JP3 and

JP4 normally have shorting plugs installed as shown in Figure 8.8.2. JP3 connects ADC0 to the yellow

potentiometer. Clockwise rotation of the potentiometer increases the voltage. JP4 connects ADC1 to a

thermistor temperature sensor. The DNT90 has its own boot loader utility that allows the protocol firm-

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ware to be installed with a terminal program that supports YMODEM. The boot loader is activated with a

shorting plug on JP13. Pin strip J6 provides access to various DNT90 pins as shown on the silkscreen.

Pressing switch SW3 will reset the DNT90P. Switch S4 is not used with the DNT90.

Figure 8.8.3

Figure 8.8.3 shows the connectors to the left of the DNT90P mounting socket. Pressing switch SW1

switches GPIO0 from logic high to low, and pressing SW2 switches GPIO1 from logic high to low. The

DNT90P interface board includes a 5 V regulator to regulate the input from the 9 V wall-plug power sup-

ply. Do not attempt to use the 9 V wall-plug power supply to power the DNT90P directly. The maximum

allowed voltage input to the DNT90P is 5.5 V.

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9.0 Troubleshooting

DNT90 not responding - make sure /RESET is not asserted (logic low). Make sure the host serial port

settings match the DNT90 serial port settings.

Can not enter protocol mode - make sure the host data rate is correct. The DNT90 defaults to 9.6 kbps. If

using the EnterProtocolMode command, send the complete protocol format for this command.

A remote never detects carrier (DCD) - check that the base is running, and that the remote’s Sys-

temNwkID is the same as the base, and that the ParentNwkID parameter is the same as the base, or is

set to 0xFF. Also make sure that the security keys are the same.

Carrier is detected, but no data appears to be received - if /HOST_RTS is enabled, make sure it is as-

serted (logic low) to enable character flow from the DNT90.

Range is extremely limited - this is usually a sign of a poor antenna connection or the wrong antenna.

Check that the antenna is firmly connected. If possible, remove any obstructions near the antenna.

9.1 Diagnostic Port Commands

The diagnostic port shares its RX and TX signal lines with the Activity and DCD indications, respectively.

Consequently, the debug port feature must be enabled before being used (Bank 0xFF). The change must

be saved and the module then needs to be reset for this to take effect. The diagnostic port is defaulted to

38.4 kbps, 8N1.

The diagnostic port supports the following user commands:

rbr <bank> <reg> <span> - read a parameter register’s value from the module.

rbw <bank> <reg> <span> <value> [<value> <value>] - write a parameter register’s value

with a span of up to 3 bytes

stat <option> - option = 0 is off, option = 1 displays DataTx/AckRx for a hop

sequence in time order, and option = 2 displays any packet RX or packet error for a hop

sequence in frequency order.

base <0 or 1> - For a router, this determines whether the stat option displays data

associated with its operation as a base (1) or as a remote (0).

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10.0 Appendices

10.1 Ordering Information

DNT90C: transceiver module for solder-pad mounting, for use with external antenna

DNT90P: transceiver module for pin-socket mounting, for use with external antenna

DNT90CA: transceiver module for solder-pad mounting, includes on-board chip antenna

DNT90PA: transceiver module for pin-socket mounting, includes on-board chip antenna

10.2 Technical Support

For DNT90 technical support call RFM at (678) 684-2000 between the hours of 8:30 AM and 5:30 PM

Eastern Time

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10.3 DNT90/DNT90A Mechanical Specifications

1 . 4 5 0

( 3 6 . 8 )

0 . 9 8 0

( 2 7 . 9 )

D N T 9 0 C O u t l i n e a n d M o u n t i n g D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

0 . 1 2 5

( 3 . 1 8 )

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 0 9 0

0 . 4 5 0 ( 1 1 . 4 ) 0 . 3 0 0 ( 7 . 6 2 )

Figure 10.3.1

0 . 0 6 0 ( 1 . 5 2 )

1 . 4 5 0 ( 3 6 . 8 )

0 . 9 8 0

( 2 4 . 9 )

D N T 9 0 C S o l d e r P a d D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 0 3 5 ( 0 . 8 9 )

1 . 0 4 0

( 2 6 . 4 )

Figure 10.3.2

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0 . 0 6 0

( 1 . 5 2 )

1 . 4 5 0

( 3 6 . 8 )

1 . 1 0 0

( 2 7 . 9 )

D N T 9 0 P O u t l i n e a n d M o u n t i n g D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

0 . 1 2 5

( 3 . 1 8 )

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 4 5 0 ( 1 1 . 4 )

0 . 0 9 0

( 2 . 2 9 )

0 . 2 2 5

( 5 . 7 2 )

0 . 9 8 0

( 2 4 . 9 )

0 . 3 0 0 ( 7 . 6 2 )

Figure 10.3.3

0.980

( 2 4 . 9 )

0.050

( 1 . 2 7 )

0.700

( 1 7 . 8 )

0.100

( 2 . 5 4 )

0.800

( 2 0 . 3 )

D N T 9 0 P I n t e r f a c e C o n n e c t o r

P C B L a y o u t D e t a i l

C o n n e c t o r s a r e S A M T E C

S L M - 1 1 5 - 0 1 - G - S

o r E q u i v a l e n t

D i m e n s i o n s a r e i n i n c h e s ( m m )

Figure 10.3.4

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1 . 8 0 0

( 4 5 . 7 )

0 . 9 8 0

( 2 4 . 9 )

D N T 9 0 C A O u t l i n e a n d M o u n t i n g D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

0 . 1 2 5

( 3 . 1 8 )

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 0 8 0

0 . 4 5 0 ( 1 1 . 4 )

A n t e n n a

0 . 6 5 0 ( 1 6 . 5 )

Figure 10.3.5

0 . 0 6 0 ( 1 . 5 2 )

1 . 8 0 0 ( 4 5 . 7 )

0 . 9 8 0

( 2 4 . 9 )

D N T 9 0 C A S o l d e r P a d D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 0 3 5 ( 0 . 8 9 )

1 . 0 4 0

( 2 6 . 4 )

0 . 4 5 0 ( 1 1 . 4 )

Figure 10.3.6

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1 . 8 0 0

( 4 5 . 7 )

1 . 1 0 0

( 2 7 . 9 )

D N T 9 0 P A O u t l i n e a n d M o u n t i n g D i m e n s i o n s

0 . 0 5 0 ( 1 . 2 7 )

T o p V i e w

0 . 1 2 5

( 3 . 1 8 )

1 5

1 6 3 0

D i m e n s i o n s i n i n c h e s ( m m )

0 . 4 5 0 ( 1 1 . 4 )

0 . 0 8 0

( 2 . 0 3 )

0 . 2 2 5

( 5 . 7 2 )

0 . 9 8 0

( 2 4 . 9 )

0 . 6 5 0 ( 1 6 . 5 )

A n t e n n a

0 . 1 0 0

( 2 . 5 4 )

Figure 10.3.7

0.980

( 2 4 . 9 )

0.050

( 1 . 2 7 )

0.700

( 1 7 . 8 )

0.100

( 2 . 5 4 )

0.800

( 2 0 . 3 )

D N T 9 0 P A I n t e r f a c e C o n n e c t o r

P C B L a y o u t D e t a i l

C o n n e c t o r s a r e S A M T E C

S L M - 1 1 5 - 0 1 - G - S

o r E q u i v a l e n t

D i m e n s i o n s a r e i n i n c h e s ( m m )

Figure 10.3.8

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10.4 DNT90 Development Board Schematic

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11.0 Warranty

Seller warrants solely to Buyer that the goods delivered hereunder shall be free from defects in materials

and workmanship, when given normal, proper and intended usage, for twelve (12) months from the date

of delivery to Buyer. Seller agrees to repair or replace at its option and without cost to Buyer all defective

goods sold hereunder, provided that Buyer has given Seller written notice of such warranty claim within

such warranty period. All goods returned to Seller for repair or replacement must be sent freight prepaid

to Seller’s plant, provided that Buyer first obtain from Seller a Return Goods Authorization before any

such return. Seller shall have no obligation to make repairs or replacements which are required by normal

wear and tear, or which result, in whole or in part, from catastrophe, fault or negligence of Buyer, or from

improper or unauthorized use of the goods, or use of the goods in a manner for which they are not de-

signed, or by causes external to the goods such as, but not limited to, power failure. No suit or action

shall be brought against Seller more than twelve (12) months after the related cause of action has oc-

curred. Buyer has not relied and shall not rely on any oral representation regarding the goods sold here-

under, and any oral representation shall not bind Seller and shall not be a part of any warranty.

THE PROVISIONS OF THE FOREGOING WARRANTY ARE IN LIEU OF ANY OTHER WARRANTY,

WHETHER EXPRESS OR IMPLIED, WRITTEN OR ORAL (INCLUDING ANY WARRANTY OR MER-

CHANT ABILITY OR FITNESS FOR A PARTICULAR PURPOSE). SELLER’S LIABILITY ARISING

OUT OF THE MANUFACTURE, SALE OR SUPPLYING OF THE GOODS OR THEIR USE OR DISPO-

SITION, WHETHER BASED UPON WARRANTY, CONTRACT, TORT OR OTHERWISE, SHALL NOT

EXCEED THE ACTUAL PURCHASE PRICE PAID BY BUYER FOR THE GOODS. IN NO EVENT

SHALL SELLER BE LIABLE TO BUYER OR ANY OTHER PERSON OR ENTITY FOR SPECIAL, IN-

CIDENTAL OR CONSEQUENTIAL DAMAGES, INCLUDING, BUT NOT LIMITED TO, LOSS OF PROF-

ITS, LOSS OF DATA OR LOSS OF USE DAMAGES ARISING OUT OF THE MANUFACTURE, SALE

OR SUPPLYING OF THE GOODS. THE FOREGOING WARRANTY EXTENDS TO BUYER ONLY AND

SHALL NOT BE APPLICABLE TO ANY OTHER PERSON OR ENTITY INCLUDING, WITHOUT LIMI-

TATION, CUSTOMERS OF BUYERS.

Part # M-0090-0002, Rev H