Laird LT2510 User manual

LT2510
WIRELESS MODULE
USER MANUAL
Innovative Technology
for a Connected World
www.lairdtech.com
Version 1.5
This datasheet has been downloaded fromhttp://www.digchip.com at this page

Laird Technologies is the world leader in the design and
manufacture of customized, performance-critical products
for wireless and other advanced electronics applications.
Laird Technologies partners with its customers to nd
solutions for applications in various industries such as:
Network Equipment
Telecommunications
Data Communications
Automotive Electronics
Computers
Aerospace
Military
Medical Equipment
Consumer Electronics
Laird Technologies offers its customers unique
product solutions, dedication to research and
development, as well as a seamless network of
manufacturing and customer support
facilities across the globe.
Copyright © 2011 Laid Technologies, Inc. All rights reserved.
The information contained in this manual and the accompanying software programs are copyrighted and all rights are reserved by Laird Technologies, Inc. Laird Technologies, Inc. reserves the right to make periodic
modications of this product without obligation to notify any person or entity of such revision. Copying, duplicating, selling, or otherwise distributing any part of this product or accompanying documentation/software
without the prior consent of an authorized representative of Laird Technologies,Inc. is strictly prohibited.
All brands and product names in this publication are registered trademarks or trademarks of their respective holders.
This material is preliminary
Information furnished by Laird Technologies in this specication is believed to be accurate. Devices sold by Laird Technologies are covered by the warranty and patent indemnication provisions appearing in its Terms
of Sale only. Laird Technologies makes no warranty, express, statutory, and implied or by description, regarding the information set forth herein. Laird Technologies reserves the right to change specications at any
time and without notice. Laird Technologies’ products are intended for use in normal commercial and industrial applications. Applications requiring unusual environmental requirements such as military, medical life-
support or life-sustaining equipment are specically not recommended without additional testing for such application.
Limited Warranty, Disclaimer, Limitation of Liability
For a period of one (1) year from the date of purchase by the OEM customer, Laird Technologies warrants the OEM transceiver against defects in materials and workmanship. Laird Technologies will not honor this
warranty (and this warranty will be automatically void) if there has been any (1) tampering, signs of tampering; 2) repair or attempt to repair by anyone other than an Laird Technologies authorized technician. This
warranty does not cover and Laird Technologies will not be liable for, any damage or failure caused by misuse, abuse, acts of God, accidents, electrical irregularity, or other causes beyond Laird Technologies’ control,
or claim by other than the original purchaser. In no event shall Laird Technologies be responsible or liable for any damages arising: From the use of product; From the loss of use, revenue or prot of the product; or
As a result of any event, circumstance, action, or abuse beyond the control of Laird Technologies, whether such damages be direct, indirect, consequential, special or otherwise and whether such damages are incurred
by the person to whom this warranty extends or third party. If, after inspection, Laird Technologies’ determines that there is a defect, Laird Technologies will repair or replace the OEM transceiver at their discretion. If
the product is replaced, it may be a new or refurbished product.

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LT2510
Wireless Module
REVISION HISTORY
Revision Description
Version 1.0 07/21/08 - Initial Release Version
Version 1.0.1 8/25/08 - Updated name to LT2510
Version 1.0.2 10/8/08 - Changed Modulation and RF Data Rate
Version 1.0.3 11/17/08 - Added TX API and Adjustable RF Data Rate
Version 1.0.4 1 2/4/08 - Engineering Updates
Version 1.1 03/13/09
Version 1.1.4-1 LWS-UM-LT2510 0509
Version 1.1.4-2 05/18/09 - LT2510 User Manual Updates
Version 1.1.4-3 09/15/09 - Added NZH Antenna & CE
Version 1.1.4-4 10/14/09 - LT2510 User Manual Updates and Additions
Version 1.1.4-5 11/17/09 - LT2510 User Manual Updates and Additions
Version 1.1.4-6 12/14/09 - LT2510 User Manual Updates and Additions
Version 1.1.4-7 02/15/10 - LT2510 User Manual Updates and Additions
Version 1.2 06/09/10 - LT2510 User Manual Updates and Additions
Version 1.3 08/03/10 - Full release for FW v2.4-1
Version 1.4 02/04/11 - Full release for FW v2.4-1
Version 1.5 05/06/11 - Updated default parameters in manual to
match those in module. Full release for
FW v2.9-0
REVISION
HISTORY

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Wireless Module
CONTENTS
LT2510 Transceiver Module ...........2
LT2510 Key Features ............................ 2
Overview .............................................. 2
Specications ................................3
Detailed Specications ......................... 3
Pin Denitions ...................................... 4
Block Diagram ...................................... 5
Timing Specications ........................... 6
Hop Frame ........................................... 6
Hardware Interface .......................7
Pin Descriptions .................................... 7
Theory Of Operation ......................8
Server/Client Architecture .................... 8
Adjustable RF Data Rate ....................... 8
Modes Of Operation ............................ 9
Serial Interface Baud Rate .................. 10
Interface Timeout / RF Packet Size....... 10
Flow Control ...................................... 12
Radio Congurations ......................... 12
EEPROM Parameters ....................18
Conguring The LT2510 ...............25
AT Commands ................................... 25
Command Quick Reference ............... 26
Command Descriptions ...................... 27
Special Firmware Upgrades .........33
Overview ............................................ 33
Upgrading via Windows OEM
Conguration Utility .......................... 33
Upgrading FW Commands ................ 34
Command Descriptions ...................... 35
Process to Manually Upgrade ............. 35
API Operation ..............................36
API Send Data Complete .................... 36
API Receive Packet ............................. 37
API Transmit Packet ............................ 37
Mechanical Considerations .........38
Mechanical Drawing .......................... 38
Mechanical Drawing .......................... 39
Mechanical Drawing .......................... 40
Mechanical Drawing .......................... 41
Moisture Content Warning ................ 42
Ordering Information ..................43
Product Part Numbers ........................ 43
Compliancy Information ..............44
Approved Antenna List ...................... 44
FCC/IC Requirements For
Modular Approval .............................. 45
OEM Equipment Labeling
Requirements...................................... 46
Antenna Requirements ...................... 46
Warnings Required In
OEM Manuals ..................................... 46
Regulatory Information ...............47
CE Approved Antenna List ................. 47
Japan Approved Antenna List ............ 47
Indications of Symbols on Equipment 47
Anatel Certications for Brazil............. 48
LT2510 Firmware History .............49
TABLE OF
CONTENTS

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LT2510
Wireless Module
KEY FEATURES
• Retries and acknowledgements
• Congurable network parameters
• Multiple generic I/O
• 280 kbps or 500kbps RF data stream
• Idle current draw of 12mA, sleep current
of 50uA
• Software selectable interface baud rates
from 1200 bps to 460.8 kbps
• Upgradable FW through serial port
The LT2510 Frequency Hopping Spread Spectrum Transceiver Module from Laird Technologies is the latest in robust
and easy to use radio modules. Supporting both high data rates and long ranges, the LT2510 is a great t for any
number of machine to-machine applications. The LT2510 features an easy to use serial UART with hardware ow
control for fast integration into an existing serial infrastructure.
• Low cost, low power and small size ideal
for high volume, portable and battery
powered applications
• All modules are qualied for Industrial
temperatures (-40°C to 85°C)
• Advanced conguration available using
AT commands
• Easy to use Conguration & Test Utility
software
OVERVIEW
The LT2510 is available in two versions, one with 125mW conducted output power and approved for North
American and similar markets and one with 50mW conducted output power and approved for European and similar
markets. These modules are identical except for output power, transmit power consumption, and the number of RF
Channels available. Differences between the two versions, where applicable, will be denoted based on part number.
This document contains information about the hardware and software interface between a Laird Technologies
LT2510 transceiver and an OEM Host. Information includes the theory of operation, specications, interface
denitions, conguration information and mechanical drawings.
Note: Unless mentioned specically by name, the LT2510 modules will be referred to as “radio” or “transceiver”.
Individual naming is used to differentiate product specic features. The host (PC/Microcontroller/Any device to which
the LT2510 module is connected) will be referred to as “OEM Host” or “Host.”
OVERVIEW AND
KEY FEATURES

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LT2510
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TABLE 1: LT2510 DETAILED SPECIFICATIONS
GENERAL FCC: PRM110/111/120/121 CE: PRM112/113/122/123
Form Factor SMD-ANT, SMD-U.FL, Pluggable-ANT, Pluggable-U.FL
Antenna Integrated chip antenna or external antenna through U.FL connector
Serial Interface Data Rate Baud rates from 1200 bps to 460,800 bps.
Non-standard baud rates are also supported.
Channels 42 or 78 selectable channels 42 selectable channels
Security Channelization, System ID, and Vendor ID
Minimum Flash (EEPROM) Memory Endurance 1000 Write/Erase Cycles
TRANSCEIVER
Frequency Band 2400 - 2483.5 MHz
RF Data Rate (Raw) 280kbps or 500kbps selectable
Hop Bin Spacing 900kHz over 79 hops
1500kHz over 43 hops
RF Technology Frequency Hopping Spread Spectrum
Modulation MSK
Output Power Conducted +11 to +21dBm selectable +8 to +17dBm selectable
Supply Voltage 3.3 - 3.6V ± 50mV ripple
Current Draw 100% TX 190mA 85mA
1/8 TX (when selected) 40mA 40mA
100% RX 40mA 40mA
RX average (idle current) 10mA 10mA
Deep sleep 50uA 50uA
Receiver Sensitivity (1% PER) -98 dBm at 280kbps RF Data Rate
-94 dBm at 500kbps RF Data Rate
Range
(based on external
2.5dBi antenna at
280kbps RF Data Rate)
Outdoor (line-of-sight) 2.5miles (4km) 1.5miles (2.4km)
Indoor (estimated) 1300ft (400m) 790ft (240m)
ENVIRONMENTAL
Operating Temperature Range -40°C to 85°C
Storage Temperature Range -50°C to 150°C
PHYSICAL
Dimensions SMD-ANT 1.0” x 1.54” x 0.14” (25.4mm x 39mm x 3.6mm)
Dimensions SMD-U.FL 1.0” x 1.28” x 0.14” (25.4mm x 33mm x 3.6mm)
Dimensions Pluggable-ANT 0.96” x 1.42” x 0.406” (24.3mm x 36mm x 10.3mm)
Dimensions Pluggable-U.FL 0.96” x 1.185” x 0.406” (24.3mm x 30.1mm x 10.3mm)
CERTIFICATE
FCC Part 15.247 KQL-2510100P KQL-2510100P
Industry Canada (IC) 2268C-2510100P 2268C-2510100P
CE N/A EN 300 328-2 V1.71,EN 301 489
RoHS Yes Yes
Japan PRM122: 005WWCA0358
PRM123: 005WWCA0359
Brazil (Anatel)* 3000-10-6625 No
SPECIFICATIONS
*contact your sales representative for more details

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LT2510
Wireless Module
TABLE 2: PIN DEFINITIONS FOR THE LT2510 TRANSCEIVER
SMT PIN PLUGGABLE
PIN
TYPE SIGNAL NAME FUNCTIONS
1 7 O GIO_0 Generic Output/Hop_Frame
2 6 O GIO_1 Generic Output
38 DNC Do not connect.
4 17 O GIO_2 RS-485 Driver Enable
519 O GIO_3 PWM Output
63I RXD Asynchronous serial data input to transceiver
7 2 O TXD Asynchronous serial data output from transceiver
8 10 GND GND Signal Ground
9 1 PWR Vcc 3.3 - 3.6 V ±50mV ripple (must be connected)
10 - PWR Vpa 3.3 - 3.6 V ±50mV ripple (must be connected)
11 - GND GND Signal Ground
12 9 I Force
9600
Force 9600 – When pulled logic Low and then applying power or resetting,
the transceiver’s serial interface is forced to a 9600, 8-N-1 rate.
Note: Because this mode disables some modes of operation, it should not be
permanently pulled Low during normal operation.
13 14 I GIO_4 Generic Input
14 5I μP_Reset RESET – Controlled by the LT2510 for power-on reset if left
unconnected. After a stable power-on reset, a logic Low pulse will reset the
transceiver.
15 11 I CMD/Data When logic Low, the transceiver interprets incoming OEM Host data as
command data. When logic High, the transceiver interprets OEM Host data
as transmit data.
16 15 O In Range When logic Low, the client is in range and synchronized with a server.
This will always be Low on a Server.
17 16 I RTS Request to Send. Floats high if left unconnected. When enabled in EEPROM,
the module will not transmit data out the Serial UART unless the pin is Low
18 12 O CTS Clear to Send - CTS is used for hardware ow control. CTS will toggle
high when the input buffer reaches the CTS On threshold until the buffer
recedes below CTS Off.
19 18 GIO_8 Generic Input*
20 13 GIO_5 Reserved for future use. Do not connect.
21 4 GIO_6 Reserved for future use. Do not connect.
22 20 I GIO_7 Analog to Digital Input
* Pin 18 (GIO_8) on board revisions 0050-00203 Rev 0 and 0050-00196 rev 2 (and below) is internally not connected.
This pin is unavailable as a GPIO on these boards.
SPECIFICATIONS
ENGINEER’S TIP
• All I/O is 3.3V TTL.
• All inputs are weakly pulled High via a 20kOhm pull-up resistor and may be left oating during normal operation
• Minimum Connections: VCC, VPA, GND, TXD, & RXD
• Signal direction is with respect to the transceiver
• Unused pins should be left disconnected

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TABLE 3: INPUT CHARACTERISTICS
SIGNAL NAME MIN HIGH HIGH MAX LOW MIN LOW MAX
UP_Reset 0.8v Vcc 0v 0.6v
RTS 2.31v Vcc 0v .99v
AD_In N/Av Vcc 0v N/A
All other inputs 70% Vcc Vcc 0v 30% Vcc
TABLE 4: OUTPUT CHARACTERISTICS
SIGNAL NAME MIN HIGH HIGH MAX LOW MIN LOW MAX SINK CURRENT
GO_0 2.5v 3.3v 0v 0.4v 20mA
GO_1 2.5v 3.3v 0v 0.4v 20mA
PWM_Output N/A 3.3v 0v N/A 4mA
All other inputs 2.5v 3.3v 0v 0.4v 4mA
BLOCK DIAGRAM
Figure 1 includes a functional Block Diagram of the transceiver module.
SPECIFICATIONS

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LT2510
Wireless Module
SPECIFICATIONS TABLE 5: TIMING SPECIFICATIONS
PARAMETER SERVER/CLIENT MIN TYP MAX NOTES
Power on to CTS Low 5ms 10ms N/A The rst boot after a FW upgrade will
require more than the typical amount
of time for CTS to toggle Low.
EEPROM Read 800us 1ms 2ms Measured from last byte of
command to rst byte of response:
870us for 1 byte
1.1ms for 80bytes
1.4ms for 256bytes
EEPROM Write 20ms 30ms 40ms Measured. EEPROM writes will
cause the radio to resyncrhonize
Power on to In Range Client only,
server will go
in range in less
than 13ms
13ms 600ms 1700ms* *Maximum time assuming all
beacons are heard, RF interference
could extend the maximum time
indenitely
Hop Period In Range 13.19ms
Hop Period Out of Range Client only 38.4ms
Reset Pulse 250ns
PWM Output Period 315.077uS
Restore Default EEPROM
Command
10ms 38ms Restore command also initiates
a soft reset, so monitoring CTS is
the best indication of a completed
command
Non Specic AT Command 1ms 10ms Some AT Commands could wait
indenitely for a response
Write Flash For FW Upgrade
Read Flash
Decrypt Image
RF HOP FRAME
The LT2510 will hop every 13.19ms and can be congured for two different RF Data Rates to provide
options for range or throughput. During each hop, the LT2510 reserves a certain amount of time for
overhead, such as the synchronization beacon, internal messaging and user data transmission. The
diagrams below outline the various transmissions that occur during a hop. These transmissions are
transparent to the user sending data, but may be useful for applications that require critical timing.
User data is only transmitted during the data slots and after the Interface Timeout or RF Packet
Size criteria has been met. Data transmission will only begin at the beginning of a data slot. When
congured for Full Duplex, data slot 1 is reserved for the Server and data slot 2 is shared by all Clients
for transmissions.
Beacon
Data Slot 1
(Max 239 Bytes)
Reserved
Data Slot 2
(Max 239Bytes)
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
DataSlot 1
(Max 96 Bytes)
Reserved
Data Slot 2
(Max 96Bytes)
RF Data Rate = 500kbps
RF Data Rate = 280kbps
13.19ms
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
Data Slot 1
(Max 239 Bytes)
Reserved
Data Slot 2
(Max 239Bytes)
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
DataSlot 1
(Max 96 Bytes)
Reserved
Data Slot 2
(Max 96Bytes)
RF Data Rate = 500kbps
RF Data Rate = 280kbps
13.19ms
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
Data Slot 1
(Max 239 Bytes)
Reserved
Data Slot 2
(Max 239Bytes)
1.19ms 4.89ms 4.89ms
2.22ms
Beacon
DataSlot 1
(Max 96 Bytes)
Reserved
Data Slot 2
(Max 96Bytes)
RF Data Rate = 500kbps
RF Data Rate = 280kbps
13.19ms
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
Data Slot 1
(Max 239 Bytes)
Reserved
Data Slot 2
(Max 239Bytes)
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
DataSlot 1
(Max 96 Bytes)
Reserved
Data Slot 2
(Max 96Bytes)
RF Data Rate = 500kbps
RF Data Rate = 280kbps
13.19ms
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
Data Slot 1
(Max 239 Bytes)
Reserved
Data Slot 2
(Max 239Bytes)
1.19ms 4.89ms 4.89ms 2.22ms
Beacon
DataSlot 1
(Max 96 Bytes)
Reserved
Data Slot 2
(Max 96Bytes)
RF Data Rate = 500kbps
RF Data Rate = 280kbps
13.19ms
1.19ms
4.89ms 4.89ms 2.22ms

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HARDWARE
INTERFACE
PIN DESCRIPTIONS
RXD and TXD
The LT2510 accepts 3.3 VDC TTL level asynchronous serial data from the OEM Host via the RXD pin. Data is sent
from the transceiver, at 3.3V levels, to the OEM Host via the TXD pin. Pins should be left oating or high when not in
use. Leaving the RXD tied Low will result in the radio transmitting garbage serial data across the RF.
Force 9600
When pulled logic Low before applying power or resetting, the transceiver’s serial interface is forced to 9600, 8-N-1
(8 data bits, No parity, 1 stop bit): regardless of actual EEPROM setting. The interface timeout is also set to 3 ms and
the RF packet size is set to the default size for the selected RF Data Rate. To exit, the transceiver must be reset or
power-cycled with Test pin logic High or disconnected.
When enabled in the EEPROM, 9600 Boot Option causes the 9600 pin to be ignored on cold boot (power-up),
command boot (0xCC 0xFF) and brown-out conditions. Therefore, the 9600 pin is only observed on warm boots
(reset pin toggled). This can be helpful so that brown-out conditions don’t cause the baud rate to change if the
9600 pin happens to be Low at the time. When 9600 Boot Option is disabled, the 9600 pin will be used for all boot
conditions. 9600 Boot Option is enabled by default.
Force 9600 also is used to wake the radio from sleep. When the pin is taken Low, the radio will wake. The transceiver
will not sleep if the pin is Low when the sleep command is issued.
Note: Because this pin disables some modes of operation, it should not be permanently pulled Low during
normal operation.
μP_RESET
μP_Reset provides a direct connection to the reset pin on the LT2510 microprocessor and is used to force a hard
reset. For a valid reset, reset must be asserted Low for an absolute minimum of 250 ns.
Command/Data
When logic High, the transceiver interprets incoming serial data as transmit data to be sent to other transceivers.
When logic Low, the transceiver interprets incoming serial data as command data. When logic Low, data packets
from the radio will not be transmitted over the RF interface however incoming packets from other radios will still
be received. Enabling CMD/Data RX Disable in the EEPROM will cause incoming RF packets to be queued by the
receiving radio while CMD/Data is Low. When CMD/Data goes High, the data will be sent over the serial interface.
In_Range
The In Range pin will be driven Low when a Client radio’s frequency hopping is synchronized with that of a Server.
In Range will always be driven Low on a server. Following boot, In Range will transition Low in approximately 12ms
on a Server. For a Client the In Range will take an average of 500ms, this time is dependant on the signal strength
of the received beacon, the presence and strength of interference and randomness of the sync function. It can vary
from 150ms to over 1500ms.
GO_0/Hop_Frame
The Hop Frame indicator functionality is disabled by default and controlled by the Control 1, Bit-6 EEPROM Setting.
When enabled this pin will transition logic Low at the start of a hop and transition logic High at the completion of
a hop. The OEM Host is not required to monitor Hop Frame.
RTS Handshaking
With RTS mode disabled, the transceiver will send any received data to the OEM Host as soon as it is received.
However, some OEM Hosts are not able to accept data from the transceiver all of the time. With RTS enabled in
EEPROM, the OEM Host can prevent the transceiver from sending it data by de-asserting RTS (High). Once RTS is
re-asserted (Low), the transceiver will send packets to the OEM Host as they are received.
Note: Leaving RTS de-asserted for too long can cause data loss once the transceiver’s transmit buffer reaches capacity.
CTS Handshaking
If the transceiver buffer lls up and more bytes are sent to it before the buffer can be emptied, data loss will occur.
The transceiver prevents this loss by deasserting CTS High as the buffer lls up and asserting CTS Low as the buffer is
emptied. CTS should be monitored by the Host device and data ow to the radio should be stopped when CTS is High.
DE/RE
When enabled, RS-485 Data Enable, will use the DE/RE pin to control the DE pin on external RS-485 circuitry. When the
transceiver has data to send to the host, it will assert DE/RE High, send the data to the host, and then take DE/RE Low.
PWM Output
PWM ouput can be congured to output on any of three pins (SMT Pins 5, 6 or 7). The PWM Output can optionally
produce a pulse width modulation for RSSI with a period of 315.077uS.

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THEORY OF
OPERATION
SERVER/CLIENT ARCHITECTURE
The LT2510 utilizes a server-client network architecture to synchronize the frequency hopping. Each network must
have one radio congured as a Server and all other radios congured as Clients. When a radio is congured as a
Server, it will transmit a beacon containing timing and identication information at the beginning of each hop. The
beacon is never visible to the OEM host. Upon boot, radios congured as Clients will enter receive mode where they
are scanning the available frequencies listening for a beacon from a Server in their network. When a Client detects
the Server’s beacon, the client will synchronize it’s frequency hopping to that of the Server and transition the InRange
pin Low. When the Server and the Client are synchronized they can begin transferring data.
Each network consists of one, and only one, Server. Multiple networks can exist in the same area, provided the
networks are congured on different Channels. The LT2510 utilizes an intelligent Frequency Hopping algorithm
which ensures minimal interference between networks. The possible interference between collocated networks is
given by the equation.
Maximum number of interfering bins = # of collocated Servers -1
For example, with 10 collocated networks, there will be up to 9 bins every hop cycle that are occupied by more than
one network at the same time. Although two or more networks might occupy the same hop bin at the same time,
there will truly only be interference if two or more radios from alternate networks are trying to transmit on the same
bin at the same time in the same coverage area.
ADJUSTABLE RF DATA RATE
The LT2510’s RF data rate can be adjusted to provide a trade-off between throughput and range.
PRODUCT MODEL RF PROFILE RF DATA RATE NUMBER OF HOPS RECEIVER SENSITIVITY THROUGHPUT1
PRM110, 111, 112, 113,
120, 121, 122, 123
0x00 500 kbps 43 -94 dBm 250 kbps
PRM110, 111, 120, 121 0x01 280 kbps 79 -98 dBm 120 kbps
PRM110, 111, 112, 113,
120, 121, 122, 123
0x03 280 kbps 43 -98 dBm 120 kbps
TABLE 6: RF DATA RATE
1 Throughput is ideal, one direction, with no retransmissions. All practical RF applications should allow for the retransmission of data due to
interference or less than ideal RF conditions.
Deciding which RF Data Rate to choose depends on the individual application. The fast RF Data Rate will deliver
much faster throughput, but will have much less range. In addition, because the lower data rate solution uses more
hops, it is better situated for collocated networks. In rmware version 1.2-5 and above the RF Data rate is set by the
appropriate RF Prole, EEPROM Address 0x54.
A rule of thumb for RF systems is every 6dB of gain doubles the effective distance. The 4dB increase of Receive
Sensitivity for the lower data rate solution means it will be able to transmit almost 60% farther than the higher data
rate solution.

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MODES OF OPERATION
The LT2510 has three different types of interface modes:
• Transparent Mode
• API Mode
• Command Mode
The rst two modes are used to transmit data across the RF, the third mode is used to congure the radio.
Transparent Mode
When operating in transparent mode, the LT2510 can act as a direct serial cable replacement in which RF data is
forwarded over the serial interface and vice versa. In transparent mode, the radio needs to be programmed with the
MAC Address of the desired recipient. The destination address can be programmed permanently or on-the-y.
When Transparent Mode is used, data is stored in the RX buffer until one of the following occurs:
• The RF packet size is reached (EEPROM address 0x5A)
• An Interface Timeout occurs (EEPROM address 0x58)
All parameters can be congured by entering Command Mode using either AT commands or by toggling the
Command/Data pin Low on the transceiver.
Transparent Mode is the default radio operation mode.
API Modes
API Mode is an alternative to the default Transparent operation of the LT2510 and provides dynamic packet routing
and packet accounting abilities to the OEM Host without requiring extensive programming by the OEM Host. API
Mode utilizes specic frame-based packet formats; specifying various vital parameters used to control radio settings
and packet routing on a packet-by-packet basis. The API features can be used in any combination that suits the
OEM’s application specic needs.
The LT2510 has three API functions:
• Transmit API
• Receive API
• Send Data Complete
For additional details and examples, please refer to the API section of the manual.
Command Mode
Command Mode is used to congure and poll for status of the transceiver. Command mode can be entered by
issuing the Enter AT Command string or by setting the CMD/Data pin Low. Details of using Command Mode to
congure the LT2510 are detailed in Conguring the LT2510 section.
THEORY OF
OPERATION

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LT2510
Wireless Module
SERIAL INTERFACE BAUD RATE
In order for the OEM Host and a transceiver to communicate over the serial interface they need to have the
same serial data rate. This value determines the baud rate used for communicating over the serial interface to a
transceiver. For a baud rate to be valid, the calculated baud rate must be within ±3% of the OEM Host baud rate
DESIRED BAND RATE BAUD (0x42) MINIMUM INTERFACE TIMEOUT1 (0x58)
230,400 0x0A 0x02
115,20020x09 0x02
57,600 0x08 0x02
38,400 0x07 0x02
28,000 0x06 0x03
19,200 0x05 0x05
14,400 0x04 0x07
9,600 0x03 0x10
4,800 0x02 0x15
2,400 0x01 0x2A
1,200 0x00 0x53
Non-standard 0xE3 Use equation below
TABLE 7: BAUD RATE/INTERFACE TIMEOUT
1 Interface Timeout = 200uS per increment, the EEPROM address 0x58 is ignored if Auto Cong is enabled. To use a non-standard
Interface Timeout, disable Auto Cong.
2 Default baud rate.
For baud rates other than those shown in Table 7 the following equations can be used:
Where:
FREQUENCY = 26 MHz
BAUD_M = EEPROM Address 0x43
BAUD_E = EEPROM Address 0x44
Baud Rate = (256 + BAUD_M) * (2BAUD_E) * FREQUENCY
228
Minimum Interface Timeout = 100,000
Baud Rate
INTERFACE TIMEOUT/RF PACKET SIZE
Interface Timeout
Interface Timeout species a maximum byte gap between consecutive bytes. When that byte gap is exceeded,
the bytes in the transmit buffer are processed as a complete packet. Interface Timeout (EEPROM address 0x58), in
conjunction with the RF Packet Size, determines when a buffer of data will be sent out over the RF as a complete RF
packet, based on whichever condition occurs rst. Interface Timeout is adjustable in 200us increments and should be
equal to or greater than two full bytes times. The minimum Interface Timeout is 0x02.
The radio will use the default Interface Timeout for a given baud rate if Auto Cong is enabled, despite what is
written in the Interface Timeout address. To use a non-standard Interface Timeout, the OEM would need to disable
Auto Cong.
ENGINEER’S TIP
• The LT2510 supports a majority of standard as well as non-standard baud rates. To select a standard baud
rate, use the value shown for EEPROM address 0x42 in Table 7 above. To enable a non-standard baud
rate, program EEPROM address 0x42 (Custom Baud Enable) to 0xE3 and then use the equation above to
solve for BAUD_M and BAUD_E.
• Adjusting the Serial Interface Baud Rate does not affect the RF data rate.
• Radio can accept Serial combinations (number of bits, Parity, Number of Stop Bits) of 8-N-1, 7-N-2, 7-1-1,
by Default. Modes of 8-1-1, 8-N-2, 7-1-2 are acceptable with 9-bit mode enabled.
THEORY OF
OPERATION

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LT2510
Wireless Module
RF Packet Size
RF Packet Size is used in conjunction with Interface Timeout to determine when to delineate incoming data as
an entire packet based on whichever condition is met rst. When the transceiver receives the number of bytes
specied by RF Packet Size (EEPROM address 0x5A) without experiencing a byte gap equal to Interface Timeout,
that block of data is processed as a complete packet. Every packet the transceiver sends over the RF contains extra
header bytes not counted in the RF Packet Size. Therefore, it is much more efcient to send a few large packets
than to send many short packets. The maximum RF Packet Size is 239 bytes, or 0xEF, at 500kkbps RF Data Rate and
96 bytes, or 0x60, at 280kbps RF Data Rate.
The RF Packet Size in Address 0x5A will not be used if Auto Cong (Address 0x56, bit 0) is enabled. The default
for the RF Data Rate will be used instead. The RF Packet Size should not be set to less than 0x07, to ensure AT
commands can still be issued.
RF Packet Size is also used by the radio to determine the number of data slots per hop. In order to efciently
transmit data across the RF the radio will automatically add more data slots to the hop to correspond to a smaller RF
Packet size. The number of slots per hop is given in the table below.
RF Data Rate RF Packet Size Number of Data Slots
280kbps 0x01 – 0x09 4 slots
280kbps 0x0A – 0x25 3 slots
280kbps 0x26-0x60 2 slots
500kbps 0x01 – 0x0C 6 slots
500kbps 0x0D – 0x25 5 slots
500kbps 0x026 – 0x47 4 slots
500kbps 0x48 – 0x7D 3 slots
500kbps 0x7E – 0xEF 2 slots
THEORY OF
OPERATION
ENGINEER’S TIP
• The more slots per hop, the less likely that retries will occur on a new frequency, this may reduce the
effectiveness of the module as a Frequency Hopping radio.
• Idle current consumption will increase as more slots are added.
• You need to use the same number of slots for every radio on the network.
• Full duplex still only reserves the rst slot for the Server. If there are 6 slots, the rst slot is reserved for the
Server to transmit and the remainder is shared by the Clients.
RS-485 Data Enable
The Timing of the DE-RE pin will vary depending on the Interface Baud Rate selected. Prior to rmware v2.2, these
parameters are set automatically if Auto Cong is enabled. If Auto Cong is Disabled, these values must be set
correctly, even if RS-485 Data Enable is not being used. In v2.2 and beyond these parameters are not controlled by
Auto Cong, but instead by Address 0x57, bit 5.
The values to set are: 485_Delay_H: Address 0x49
485_Delay_M: Address 0x4A
485_Delay_L: Address 0x4B
To set them, use the equation (round the result up):
Address 0x49 and 0x4A: 485H/M = 8.125MHz / (81*Baud_Rate), quotient only
Address 0x4B: 485L = (8.125MHz / Baud_Rate) mod 81
So for 19,200 you should calculate 00 05 12

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LT2510
Wireless Module
FLOW CONTROL
Although ow control is not required for transceiver operation, it is recommended to achieve optimum system
performance and to avoid overrunning the LT2510’s serial buffers. The LT2510 uses separate buffers for incoming
and outgoing data.
RXD Data Buffer And CTS
As data is sent from the OEM Host to the radio over the serial interface, it is stored in the LT2510’s buffer until the
radio is ready to transmit the data packet. The radio waits to transmit the data until one of the following conditions
occur (whichever occurs rst):
• The RF packet size is reached (EEPROM address 0x5A)
• An Interface Timeout occurs (EEPROM address 0x58)
The data continues to be stored in the buffer until the radio receives an RF Acknowledgement (ACK) from the
receiving radio (addressed mode), or all transmit retries/broadcast attempts have been utilized. Once an ACK has
been received or all retries/attempts have been exhausted, the current data packet is removed from the buffer and
the radio will begin processing the next data packet in the buffer.
To prevent the radio’s RXD buffer from being overrun, it is strongly recommended that the OEM Host monitor the
radio’s CTS output. When the number of bytes in the RXD buffer reaches the value specied by CTS_ON (EEPROM
address 0x5C - 0x5D), the radio de-asserts (High) CTS to signal to the OEM Host to stop sending data over the serial
interface. CTS is re-asserted after the number of bytes in the RXD buffer is reduced to the value specied by CTS_OFF
(EEPROM addresses 0x5E- 0x5F); signalling to the OEM Host that it may resume sending data to the transceiver.
Note: It is recommended that the OEM Host cease all data transmission to the radio while CTS is de-asserted (High);
otherwise potential data loss may occur.
TXD Data Buffer And RTS
As data to be forwarded to the OEM Host accumulates, it is stored in the LT2510’s outgoing buffer until the radio
is ready to begin sending the data to the OEM Host. Once the data packet has been sent to the Host over the
serial interface, it will be removed from the buffer and the radio will begin processing the next data packet in the
buffer. With RTS Mode disabled, the transceiver will send any data to the OEM Host as soon as it has data to send.
However, some OEM Hosts are not able to accept data from the transceiver all of the time. With RTS Mode Enabled,
the OEM Host can prevent the transceiver from sending it data by de-asserting RTS (High), causing the transceiver to
store the data in its buffer. Upon asserting RTS up to two additional bytes can be received over the serial interface
before the ow is stopped. Once RTS is re-asserted (Low), the transceiver will continue sending data to the OEM
Host, beginning with any data stored in its buffer.
Note: Leaving RTS de-asserted for too long can cause data loss once the radio’s TXD buffer reaches capacity.
ENGINEER’S TIP
Can I implement a design using just TXD, RXD and Gnd (Three-wire Interface)?
Yes. However, it is strongly recommended that your hardware monitor the CTS pin of the radio. CTS is
taken High by the radio when its interface buffer is getting full. Your hardware should stop sending at this
point to avoid a buffer overrun (and subsequent loss of data). You can perform a successful design without
monitoring CTS. However, you need to take into account the amount of latency the radio adds to the
system, any additional latency caused by retries, how often you send data, non-delivery network timeouts
and interface data rate. Laird Technologies can assist in determining whether CTS is required for your
application.
THEORY OF
OPERATION
RADIO CONFIGURATIONS
Auto Channel (EEPROM 0x56, bit 3)
To allow for more exible network congurations, Auto Channel can be enabled in clients to allow them to
automatically synchronize with the rst server they detect, regardless of channel number.
Note: A client with Auto Channel will only synchronize with a server having a matching System ID
Auto Cong (EEPROM 0x56 bit 0)
The optimal settings for Interface Timeout and RF Packet Size vary according to the selected RF Prole and Interface
Baud Rate. Enabling Auto Cong will bypass the value for these variables stored in EEPROM and use predetermined
values that have been optimized for the given mode. When Auto Cong is disabled, these values must be
programmed in the transceiver EEPROM.

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LT2510
Wireless Module
THEORY OF
OPERATION
Auto Destination (EEPROM 0x56, bit 4)
To simplify EEPROM programming, Auto Destination can be enabled in the radio which allows the radio to
automatically set its destination to the address of the radio from which it last received a successful transmission
from (beacon or data packet).
Auto Destination on Beacons Only (Address 0x56, bit 7)
When Auto Destination is enabled, the Client radio will address itself to the source of any received packet, including
beacons from the server and any addressed or broadcast packets it receives. For point to multipoint networks where
the Client is intended to only communicate back to the Server, this could cause the Client to inadvertently become
addressed to another Cleint. By enabling Auto Destination on Beacons Only, the Client will only address itself upon
reception of Beacons, therefore it will only address itself to the Server. Auto Destination on Beacons Only is only
functional when Auto Destination is also enabled.
Auto System ID (EEPROM 45, bit 4)
When enabled this will allow a client to attach to any server on the same RF Channel, regardless of the System ID on
the server or the client.
Beacon Skip (EEPROM 0x6F)
When set, the transceiver will send (Server) or listen (Client) for a beacon on hops spaced by the Beacon Skip
number. On a Client, once the Beacon Skip count is reached the Client will listen every hop until it successfully hears
a beacon. It will then wait a number of hops specied by the Beacon Refresh before listening again.
Enabling this will allow the transceiver to conserve power by disabling its RF circuitry during the beacon time.
Enabling this on the Server will cause substantially longer sync times on the Clients.
Broadcast (EEPROM 0xC1, bit 7)
In Broadcast mode, the transceiver will transmit the packet to all transceivers with the same Channel Number and
System ID settings. There is no RF acknowledgement sent from the recipient(s) back to the transmitter, therefore the
packet is sent out the number of times specied by Broadcast Attempts.
Broadcast Attempts (EEPROM 0x4D)
When transmitting broadcast packets, the RF packet is broadcast out to all eligible receivers on the network.
Broadcast Attempts is used to increase the odds of successful delivery to the intended receivers. Transparent to the
OEM host, the transmitter will send the RF packet to the receivers. If a receiver detects a packet error, it will throw
out the packet. This will continue until the transmitter exhausts all of its attempts. Once the receiver successfully
receives the packet it will send the packet to the OEM host. It will throw out any duplicates caused by further
Broadcast Attempts. The received packet will only be sent to the OEM host if it is received free of errors. Because
broadcast packets have no RF acknowledgement, each packet is transmitted the number of times specied by
Broadcast Attempts. This makes for very inefcient use of the available bandwidth; therefore, it is recommended that
Broadcast Attempts be set as Low as possible and that broadcast packets be limited in use.
Note: Setting to 0 is equal to 256.
Destination Address (EEPROM 0x70-0x75)
The Destination Address is simply the MAC (IEEE) address of the intended receiver on the network. In Addressed
Mode, the RF packet is sent out to the intended receiver designated by the Destination Address. Only the four
LSBs (Least Signicant Bytes) of the Destination Address are actually used for packet delivery. This eld is ignored if
Broadcast Mode, Auto Destination or Transmit API is enabled.
Disable Status Bin (EEPROM 0xC1, bit 4)
When set, disables the reception on the status slot of the bin. The result is that the Bin Analyzer and Remote I/O
functionality will be disabled on the radio with the benet of saving approximately 1mA average current consumption.
Discard Framing Error Packets (EEPROM 0x57, bit 7)
When set, the radio checks for a framing error in the UART buffer before processing incoming data. If an error is
detected on any of the bytes in the buffer, the entire buffer is discarded.

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LT2510
Wireless Module
THEORY OF
OPERATION
Full Duplex (EEPROM 0x56, bit 1)
In Half Duplex mode, the transceiver will send a packet out over the RF immediately. This can cause packets sent at
the same time by a server and a client to collide with each other over the RF. To prevent this, Full Duplex Mode can
be enabled. This mode reserves a transmit “slot” for the server. If the server does not have any data to transmit,
clients are permitted to transmit during that time. If the server does have data to send, clients will not be permitted
to transmit during that slot. Likewise, the server will not be able to transmit during a client slot. Though the RF
hardware is still technically half duplex, it makes the transceiver seem full duplex. This can cause overall throughputs
to be cut in half.
Note: All transceivers on the same network must have the same setting for Full Duplex.
Hop Packet Delineation (EEPROM 0x57, bit6)
When enabled, in addition to using RF Packet Size and Interface Timeout as criteria for processing incoming data,
the radio will also delineate packets up to once per hop once a minimum of six characters has been received over the
serial port.
Legacy RSSI (EEPROM 0x45, bit 2)
RSSI (Received Signal Strength Indicator) is a measure of how well the receiving radio is able to hear the transmitting
radio. By default, RSSI is reported in 2’s complement format, therefore, values range from 0x80 - 0x7F. Many
preceding products have, instead, reported RSSI in the range of 0x00 - 0xFF. Legacy RSSI causes 0x80 to be added
to the RSSI result prior to reporting it to the host.
Max Power (EEPROM 0x63)
The transceiver has an adjustable RF output power. Power can be adjusted dynamically to optimize communications
reliability and conserve power. Each increment represents a 3dBm 50% decrease in power. The radios have a
maximum input RF level of 0dBm. When operated very close together at full power the radio’s receiver can saturate
and no transmissions are possible. If the distance between the transmitter and receiver is very short (generally less
than 2ft (.6m) with 2.5dBi antennas), the Max Power should be reduced.
Mode (Server/Client) (EEPROM 0x41)
The server controls the frequency hop timing by sending out regular beacons (transparent to the transceiver host)
which contain system timing information. This timing information synchronizes the client radio frequency hopping to
the server. Each network should consist of only one server.
Nine Bit Mode (EEPROM 0x57, bit 1)
With Nine Bit mode disabled, the transceiver communicates over the asynchronous serial interface in 8-N-1 format
(8 data bits, No parity, 1 stop bit). Some systems require a parity or 9th data bit. Enabling Nine Bit Mode causes the
transceiver to communicate using 8-1-1 format (8 data bits, 1 parity bit and 1 stop bit). In this mode, the transceiver
will not validate the parity bit but simply transmits it over the RF. This is useful as some systems use the ninth bit as
an extra data bit and not just a parity bit. However, because the ninth bit is transmitted over the RF, enabling Nine Bit
Mode cuts the transceiver interface buffer size by 1/9 and reduces the RF bandwidth by the same ratio.
Random Backoff (EEPROM 0xC3)
The transceivers utilize a Carrier Sense Multiple Access (CSMA) protocol with Random Backoff and a programmable
back-off seed. Therefore, in the event of a collision, the transceiver will back off and retry the packet. Specically,
when two transceivers collide with each other (transmitting packets at the same time), each transceiver will choose
a random number of packet times that it will wait before retrying the packet. Ideally, they will each choose a
different number and will be successful in the next transmission. A good rule of thumb is to set Random Backoff
to a number slightly larger than the maximum number of transceivers that would be expected to be transmitting at
the same time.
Range Refresh (EEPROM 0x3D)
Range refresh species the maximum amount of time a transceiver will report In Range without having heard a
server’s beacon. It is adjustable in hop periods. Do not set to 0.

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LT2510
Wireless Module
THEORY OF
OPERATION
Remote I/O Mode (Address 0x57, bit 3)
Remote I/O Mode allows GPIOs on two radios to be joined together so their states will be reected on the other
radio. Enabling Remote I/O Mode will allow the local radio to transmit its GPIO states whenever there is a change.
The states will be transmitted to the radio specied by the Destination Address (or as a Broadcast if Broadcast mode
is enabled). State information will only be transmitted when there is a change on one of the enabled Digital Inputs.
The states will be retransmitted up to the number of specied Utility Retries (Address 0x4E). Any changes to the
Digital Inputs that occur while a Utility retransmission is occurring will not be transmitted unless the change persists
until all Utility retries have been sent or an acknowledge was received. Therefore, this feature should only be used
for slow-moving changes that occur less than the time it takes to expend all retries. Remote I/O is disabled when the
Force 9600 pin is set at boot.
Remote I/O control lines occur in pairs, with the Digital Input on the local radio driving a Digital Output on the
remote radio and vice-versa. This makes Remote I/O useful for both point to point and point to multipoint networks.
Multipoint to point networks will not benet from using a single pair of lines as the central point won’t be able to
tell where the line change was sourced. Multiple control lines are available though, so up to four pairs of lines can
be used simultaneously. Likewise, analog inputs can be used (Address 0x57, bit 4) as the input (with a PWM output
on the remote radio), though analog states will only be transmitted when a Utility packet is sent, which are only
triggered by the change of a Digital Input. Threshold settings are not available on analog Inputs.
Output lines will be initialized at boot according to Remote I/O Status (Address 0xC9-0xCA) for the Digital lines and
PWM_Init (Address 0xC8) for the PWM output.
Which control lines are used in Remote I/O is set by the Remote I/O Control bit eld (Address 0x60). Note, TxD/RxD
is one pair of Remote I/O lines available. If this pair is used, the module will not respond to Commands and will not
be able to transmit or receive serial data. If this pair is enabled, Force 9600 must be Low at boot to disable Remote
I/O if serial communications are desired.
Address 0x60, Bit Input Output
Bit 0 set GIO_4 GIO_0
Bit 1 set GIO_8* GIO_1
Bit 2 set GIO_7 GIO_3
Bit 3 set CMD/Data GIO_2
Bit 4 set RTS CTS
Bit 5 set RXD TXD
Bit 6 clear, Bit 7 clear All I/O are Outputs
Bit 6 set, Bit 7 clear All I/O are Inputs
Bit 7 set Inputs and Outputs are as specied in table
*GIO_8 (Pin 18) on board revisions 0050-00203 Rev 0 and 0050-00196 rev 2 (and below) is internally not
connected. This pin is unavailable as a GPIO on these boards.
ENGINEER’S TIP
• When using GIO_7/GIO_3 Pairs, the input/output will be digital unless Remote Analog Enable bit is set
(Address 0x57, bit 4) in which case the input is Analog and the output is PWM.
• TXD and RXD are not available for UART serial data when used as in Remote I/O. Force 9600 must be
Low on boot to disable Remote I/O Mode and issue commands.
• When not using pairs (bit 7 clear), one radio should have all I/O as inputs and the other radio or radios
should have all I/O as output.
• Remote I/O Mode must be enabled on both the local and remote radio and the Remote I/O Control Bit
must be set for the same pair on both radios.
• All I/O state information for all lines is transmitted when any update is triggered. Thus, on the receiving
radio any enabled output pins will be updated, regardless of whether those pins were enabled on the
transmitting radio.
RF Channel Number (EEPROM 0x40)
This product uses FHSS (Frequency Hopping Spread Spectrum) protocol in which the transceiver will communicate
using frequency “bins” spaced throughout the frequency band. Therefore, RF Channel Number species a unique
pseudo-random hopping sequence.

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LT2510
Wireless Module
THEORY OF
OPERATION
RF Prole (EEPROM 0x54)
RF Prole can be adjusted to provide a trade-off between throughput and range. Deciding which RF Prole to
choose depends on the individual application. Selecting a higher RF baud rate will provide increased RF bandwidth.
However, selecting the lower RF baud rate will provide signicantly improved range. Selecting fewer hops provides a
shorter sync time, whereas more hops will provide better interference and collocated system immunity.
RSSI
Received Signal Strength Indicator (RSSI) is available to the OEM through a number of means. AT Commands such
as Bin Analyzer and Report RSSI will report RSSI, API Packets for Received and Send Data Complete will report RSSI
and one of three pins can be congured to provide a PWM output representing the RSSI. By default, all of these
commands, except PWM Output represent RSSI as that is a hexadecimal 2’s complement form. Legacy RSSI (detailed
above) can be enabled to provide the RSSI in a non 2’s complement form from 0x00 (very weak signal) to 0xFF (very
strong signal). The control commands for PWM output utilize a Legacy RSSI format from 0x00 to 0xFF.
The RSSI values reported can be converted to a decibel value with the following formulas:
For Non-Legacy values where the RSSI in Hexadecimal ranges from 0x80 to 0x7F:
If this value is greater than or equal to 128, then:
RSSI_dBm = (RSSI_Dec - 256)/2 - RSSI_Offset
If this value is less than 128, then:
RSSI_dBm = (RSSI_Dec)/2 - RSSI_Offset Where,
For Legacy RSSI the equation is:
RSSI_dBm = (RSSI_Dec - 128)/2 -RSSI_Offset
RSSI_Dec is the reported value represented in Decimal notation
RSSI_Offset = 82
Reported RSSI values are meant as estimate and have an accuracy of +/- 2dBm. The RSSI reported by various
commands has an effective range of -25dBm to -95dBm, outside of this range, the accuracy is not maintained.
RSSI_Control (EEPROM 0x68):
RSSI Control is a biteld used to control the output of the RSSI PWM output and what messages the radio reports
on. Note if Disable Hop Frame is Disabled (so as to report Hop Frame), it will be output on GO_0 (pin 1 of SMT
module), so the PWM Output should not be set to output to that pin or conicting signals will be sent on that
output pin.
Address 0x68, Bit Input Output
Bit 0 set GIO_4 GIO_0
Bit 1 set GIO_8* GIO_1
Bit 2 set GIO_7 GIO_3
Bit 3 set CMD/Data GIO_2
Bit 4 set RTS CTS
Bit 5 set RXD TXD
Bit 6 clear, Bit 7 clear All I/O are Outputs
Bit 6 set, Bit 7 clear All I/O are Inputs
RSSI_Lag (EEPROM 0x67)
Controls a lter on the PWM output to smooth out the changes made to the PWM signal. Setting the value to
a very Low number will result in very quick changing output. Setting the value to a higher number will result in a
slower varying PWM output. Setting the value to 0x00 will result in an instantaneous RSSI. Because RSSI is measured
per hop and the radio can hop over 43 or 79 hops, instantaneous RSSI may be too quickly moving to be of use as a
signal strength indicator. The default value is 0x40 and should be sufcient for most applications. It should be set to
a value of less than 0x80.
RSSI_Lag affects the PWM Output according to the following equations:
Cumulative_Lag = Cumulative_Lag + (RSSI_Current – Old_RSSI_Avg)
New_RSSI_Avg = Old_RSSI_Avg + (Cumulative_Lag mod EE_Lag)
Cumulative_Lag is then stored in memory until the next time RSSI is calculated.
If (Cumulative_Lag mod EE_Lag) > 0, then Cumulative_Lag = remainder of (Cumulative_Lag mod EE_Lag)

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LT2510
Wireless Module
RSSI Output to PWM
A moving RSSI Average can be written to the PWM Output as a signal strength indicator. The output pin to use, the
threshold range for the RSSI and the RSSI Type reported can all be congured through EEPROM Addresses.
The PWM Output has a 315.077uS period. The duty cycle is set by the RSSI value recorded by the transceiver and the
RSSI Threshold High and RSSI Threshold Low values
RSSI Threshold High (EEPROM 0x65)
Is the upper limit of the recorded RSSI reading. RSSI Values reported above this value (strong signals) will report a
100% Duty Cycle on the PWM Output.
RSSI Threshold Low (EEPROM 0x66)
Is the lower limit of the recorded RSSI reading. RSSI Values reported below this value (weak signals) will report a 0%
Duty Cycle on the PWM Output.
To calculate the thresholds use the equation:
RSSI_Dec = (RSSI_dBm + 82) * 2 +128
Then convert this from Decimal to Hexadecimal notation.
Sleep Indicator (EEPROM 0x45, bit 6)
When enabled, GIO_1 will toggle Low during sleep and high when the module is awake.
Sniff Permit (EEPROM 0x45, bit 0)
Sniff Permit will allow a radio to receive a data packet from another radio on the network regardless of the
Destination MAC Address in the packet. This allows an OEM to create a Sniffer for all network trafc. Sniff Permit
would need to be enabled on the transmitting radio, to grant it’s permission to be heard. Sniff Report and Sniff
Permit would need to be enabled on the sniffer radio, to cause it to send sniffed packets out the serial port.
System ID (EEPROM 0x76)
System ID is similar to a password character or network number and makes network eavesdropping more difcult.
A receiving transceiver will not go in range of or communicate with another transceiver on a different System ID.
System ID can be ignored on a Client by enabling Auto System ID
Transmit Retries (EEPROM 0x4C)
When transmitting addressed packets, the RF packet is sent out to the receiver designated by its destination address.
Transmit Retries is used to increase the odds of successful delivery to the intended receiver. Transparent to the OEM
host, the transmitter will send the RF packet to the intended receiver. If the receiver receives the packet free of errors,
it will send the transmitter an acknowledgement. If the transmitter does not receive this acknowledgement, it will
assume the packet was never received and retry the packet. This will continue until the packet is successfully received
or the transmitter exhausts all of its retries. The received packet will only be sent to the OEM host if and when it is
received free of errors.
Note: Setting to 0 is equal to 256.
Unicast Only (EEPROM 0xC1, bit 3)
To prohibit transceivers from receiving broadcast packets, Unicast Only can be enabled. Unicast Only restricts the
transceiver to only receive addressed packets.
Vendor ID
The Vendor ID, like the System ID, can be used to uniquely identify a network. Radios with the Vendor ID set, will
only communicate with other radios with the same set Vendor ID.
The Vendor ID is a protected EEPROM parameter and it’s value cannot be read. It can only be written once. OEMs
should be aware that improperly setting the Vendor ID can cause communication issues. Setting the Vendor ID to an
unknown setting will effectively render the radio unable to communicate in a network.
Note: The Vendor ID is a one-time write parameter and it cannot be read.
9600 Boot Option (EEPROM 0x57, bit 0)
When enabled, 9600 Boot Option causes the 9600 pin to be ignored on cold boot (power-up) and brown-out
conditions. Therefore, the 9600 pin is only observed on warm boots (reset pin toggled). This can be helpful so that
brown-out conditions don’t cause the baud rate to change if the 9600 pin happens to be Low at the time. When
9600 Boot Option is disabled, the 9600 pin will be used for warm and cold boots as well as brown-out conditions.
THEORY OF
OPERATION