ABB TMD-T4 - Error Messages from Slave to Master; Error Message Structure; Error Code Definitions

TMD-T4 protocol communication - instruction manual IM148-U-AB v0.92 pag. 9 / 12
ERROR MESSAGE FROM SLAVE TO MASTER
When a slave device receives a not valid query, it does transmit an error message.
RESPONSE:
START OF
FRAME
ADDRESS
FIELD
FUNCTION
CODE
ERROR
CODE
ERROR
CHECK
END OF
FRAME
START OF FRAME = Starting message marker.
ADDRESS FIELD = TMD device address (01...F7 HEX) (1 byte ).
FUNCTION CODE = Operation code with bit 7 high (1 byte).
ERROR CODE = Message containing communication failure (1 byte).
ERROR CHECK = Check sum.
END OF FRAME = End message marker.
ERROR EXAMPLE
QUERY RESPONSE
Field Name Example ( Hex) Field Name Example ( Hex)
Slave Address 01 Slave Address 01
Function Code 03 Function Code 83 (1)
Starting Address Hi 00 Error Code 02 (2)
Starting Address Lo 00 Error Check (CRC) ??
Number Of Word Hi 00 ??
Number Of Word Lo 05 (1):Function Code transmitted by master with bit 7
high.
Error Check (CRC) ?? (2): Error type:
?? 01= Illegal Function
02= Illegal data address
03= Illegal data value