ICP DAS USA I-7530A-MR-G User Manual page 104

0x03
 From Data Byte4 to Data Byte7, they indicate the "Modbus
Exception" message. The "Modbus Exception" message includes
Slave Node ID, Exception Function Code, and Exception Code.
When the Identifier code is 0x03, this message is shown in the error
response CAN message. Otherwise, these data value are 0x00.
 Modbus Exception
Byte4
Slave
Node ID
 Function Code and Exception Function Code relation
Function
Code (Hex)
0x01
0x02
0x03
0x04
0x05
0x06
0x0F
0x10
 Modbus Exception Code
About more Modbus exception code description, please refer to
the Modbus protocol specification.
 Modbus Slave Response Timeout:
This field is used for setting Modbus command timeout value. When
sending a Modbus command, the I-7530A-MR module will start to wait
for a response command from the Modbus slave device until timeout
I-7530A-MR Modbus RTU to CAN Converter User's Manual (Version 1.08, 07/2019) ------------- 104
It indicates the current Modbus command is
transmitted completely, but the I-7530A-MR
receives a "Modbus Exception" command.
Modbus Exception
Byte5
Exception
Function Code
Exception Function
Code (Hex)
0x81
0x82
0x83
0x84
0x85
0x86
0x8F
0x90
Byte6
Exception Code
Byte7
Reserved