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Rtu framing, Table 8.12, Query sample – RLE LD5100 User Manual

Page 58: Table 8.13, Response sample

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8

Modbus Communication

8.3. RTU

Framing

The example below shows a typical Query/Response from the LD5100 module.

Slave address 2 responds to Function Code 4 with 6 bytes of hexadecimal data and ends with

CRC16 checksum

Register Values:

40001 = 0000 (hex)

40002 = 0000 (hex)

40003 = 0001 (hex)

Table 8.12 Query Sample

Slave

Address

Function

Code

Starting

Register

“Msb”

Starting

Register

“Lsb”

Numbers

of

Registers

“Lsb”

Number of

Registers

“Lsb”

CRC 16

“Lsb”

CRC

“Msb”

02

04

00

00

00

03

B5

A3

Table 8.13 Response Sample

Slave

Address

Function

Code

Count

Bytes of

Data

Register

Data

Msb Lsb

Register

Data

Msb Lsb

Register

Data

Msb Lsb

CRC 16

“Lsb”

CRC 16

“Msb”

02

04

06

00

00

00 00

00 01

B5

A3