Omron RX Series User Manual page 491

Loop-back Test [08 hex]
Checks the communications between the master and the slave. Any value can be used for test data.
Example
To perform a loop-back test on the inverter with slave address 1.
Query
No.
1
Slave address
2 Function code
3 Test sub code (MSB)
4 Test sub code (LSB)
5 Data (MSB)
6 Data (LSB)
7 CRC-16 (MSB)
8 CRC-16 (LSB)
Response
No.
1
Slave address
2 Function code
3 Test sub code (MSB)
4 Test sub code (LSB)
5 Data (MSB)
6 Data (LSB)
7 CRC-16 (MSB)
8 CRC-16 (LSB)
*1 Broadcasting cannot be performed.
The test sub code supports the Echo Query Data command (00 hex, 00 hex) only. Other commands are
not supported.
High-function General-purpose Inverter 3G3RX-V1 User's Manual (I578-E1)
Field name Example [hex]
*1 01
08
00
00
Any
Any
CRC
CRC
Field name Example [hex]
*1 01
08
00
00
Any
Any
CRC
CRC
8 Communications Functions
8
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