Data Sheet

Copyright © Roboteq Inc. 2018. All Rights Reserved. 5
00 00 12 34
Value in big Indian notation (MSB first).
F6 F3
Cyclic redundancy check (CRC-16-IBM)
2.1.2 Write Multiple Holding Registers (0x10)
This function is implemented to write exactly 4 bytes (2 registers). Issuing any messages to write other
than 2 registers will have no effect.
For examples, to write 0x00001234 to VAR1, you need to write 2 registers to address 0x00A1 so you need
to send the following RTU message:
01 10 00 A1 00 02 04 00 00 12 34 35 6C
Name
Description
01
Node address
10
Function code (Write Multiple Holding Registers)
00 A1
Register address for writing VAR1
00 02
Number of registers to write (must be 2)
04
Number of bytes to be written (must be 4)
00 00 12 34
Value to be written in big Indian notation (MSB first)
35 6C
Cyclic redundancy check (CRC-16-IBM)
The response for this message will be as following:
01 10 00 A1 00 02 10 2A
Name
Description
01
Node address
10
Function code (Write Multiple Holding Registers)
00 A1
Address of written register (VAR1).
00 02
Number of registers written.
10 2A
Cyclic redundancy check (CRC-16-IBM)
2.1.3 Exception responses
Following a request, there are 4 possible outcomes from the slave:
• The request is successfully processed by the slave and a valid response is sent.
• The request is not received by the slave therefore no response is sent.
• The request is received by the slave with a parity, CRC or LRC error (The slave ignores the request
and sends no response).