REMEHA GTW-08 Modbus Konfigurationsanleitung Seite 6

en
5 Configuration
5 Configuration
5.1 Modbus
5.2 Read multiple registers
6
Red Fixed
Orange Fixed
Orange Slow blinking
(500 ms)
The following Modbus function codes are supported:
Tab.5 Modbus functions
code function
03d Read holding register
04d Read input register
06d Write single register
16d Write multiple register
The function code 03 (Hexadecimal) allows the leader device to request
information from the follower device. The command message structure is
shown below. The command message format is read from top byte to
bottom, so the follower address comes first.
Tab.6 'Read multiple registers' command format
Message Byte read position
Follower address
Function code
Starting register Upper
Lower
Quantity Upper
Lower
CRC-16 Lower
Upper
In this example, starting register will point to the 32nd decimal register,
and the quantity commands to read until decimal register 35.
Tab.7 'Read multiple registers' normal response messages
Message Byte read position
Follower address
Function code
Byte count
Starting register Upper
Lower
Next register Upper
Lower
Last register Upper
Lower
No Modbus communication available
No communication on L-Bus
GTW-08 Modbus error
Example hexadecimal
input
64
03
00
20
00
04
xx
xx
Example hexadecimal
output
64
03
06
xx
xx
xx
xx
xx
xx
7854678 - v.01 - 15092023