Advertisement
GW-7238D Quick Start v1.0 Nov. 2011
Figure 11: Parameter upload screen
Modbus Communication – Modbus RTU
Set J1939 output data
Using the Modbus command as below:
FC16 Write multiple registers (4xxxx) for AO
Example:
In the address 40001, write the value in 0x1234.
[Request Command] (Byte0, Byte1... Byten) (Hex)
01 10 00 00 00 01 02
12 34
AB 27(CRC)
Get J1939 input data
Using the Modbus command as below:
FC4 Read multiple input registers (3xxxx) for AI
Example:
Read a value of one word in the address 30001.
[Request] (Byte0, Byte1... Byten) (Hex)
01 04 00 00 00 01
31 CA(CRC)
GW-7238D responds a value of one word in the address 30001.
[Response](Byte0, Byte1... Byten) (Hex)
01 04 02
12 34
B4 47(CRC)
8 8 8 8 / / / / 12 12 12 12
Advertisement
