Diagnostic Command; Error Response - Omega i-SERIES User Manual

6.8.3 Diagnostic Command

This command echoes the sent message to indicate that the communication link is
established correctly.
SEND TO/RETURN FROM DEVICE:
DEVICE FUNCTION
ADDRESS
1 BYTE
nn
Where: Diagnostic Code is two byte code to determine the type of test to be performed.
i-Series devices supported only "00" code which requested slave to echo sent command
back to the master.
Example:
SEND TO DEVICE: Address 01, Diagnostic command (08), data value 8755 Dec
(2233 Hex)
DEVICE FUNCTION
ADDRESS CODE
01
RETURNED FROM DEVICE:
DEVICE FUNCTION
ADDRESS CODE
01

6.8.4 Error Response

When a device can not properly respond to the command due to incorrect or corrupted
command, it will respond with an error message. The error massage has the following
format:
DEVICE FUNCTION
ADDRESS CODE
1 BYTE 1 BYTE
nn
i-Series devices support the following error code messages:
02 – read from/write to the illegal register – read from/write to the register, which is
inactive, or not supported by i-Series devices
03 – write an illegal value – write out of range value
DIAGNOSTIC LOOPBACK
CODE CODE
1 BYTE HB
08 00
DIAGNOSTIC
CODE
08 22
DIAGNOSTIC
CODE
08 22
ERROR
RESPONSE
1 BYTE
nn nn
DATA
LB HB LB
00 nn nn
LOOPBACK
DATA
33 00 00
LOOPBACK/
DATA
33 00 00
CRC
LB HB
nn nn
41 41
CRC
LB HB
nn nn
CRC
BE B8
CRC
BE B8