86 YASKAWA TM.iQp.02 iQpump Drive Programming Manual
◆ Loopback Test (08H)
The loopback test returns the command message directly as the response message without changing the contents to check the
communications between the master and slave. Set user-defined test code and data values.
The following table shows a message example when performing a loopback test with the slave 1 Drive.
Figure 83 Function Code 08H Message Example
Command Message
Response Message
(During Normal Operation)
Response Message
(During Error)
Slave address 01H Slave address 01H Slave address 01H
Function code 08H Function code 08H Function code 88H
Test Code
High
Byte
00H
Test Code
High
Byte
00H Error Code 01H
Low
Byte
00H
Low
Byte
00H
CRC-16
High
Byte
86H
Data
High
Byte
A5H
Data
High
Byte
A5H
Low
Byte
50H
Low
Byte
37H
Low
Byte
37H
CRC-16
High
Byte
DAH
CRC-16
High
Byte
DAH
Low
Byte
8DH
Low
Byte
8DH