Omron SYSDRIVE 3G3MV User Manual page 213

Communications
·The DSR message or normal response for loop-back test use is divided into 8-byte
blocks as shown below. Any data can be set as test data 1 or 2 provided that the num-
ber of data items remains changed.
·This command is used for checking the status of communications or for dummy com-
munications without detecting any communications time-over.
D DSR Message
Byte No.
1 Slave address
2 Function code (08 Hex)
Test data 1 Test data 1
3
4
5 Test data 2 Test data 2
6
7 CRC-16 check CRC-16 check
8
D Response
Normal
Byte No.
1 Slave address
2 Function code (08 Hex)
3 Test data 1 Test data 1
4
5 Test data 2 Test data 2
6
7 CRC-16 check CRC-16 check
8
Error
Byte No.
1 Slave address
2 Function code (88 Hex)
3 Error code
4 CRC-16 check CRC-16 check
5
Note When an error occurs, the MSB of the function code will be set to 1.
Data
Data
Data
Chapter 7
7-19