
MANUEL STA46
Modbus TCP
JP Viskovic 30/08/2005 OEE-F
14
1-5 Error
response
If the request contains error like address or quantity out of range, the PLC program will generate an
exception response containing the exception code
[Response]
Length
Data
Function Code
1 Byte
Function Code + 0x80
Exception Code
1 Byte
01, 02 or 03
Exception Code
Name
01 ILLEGAL
FUNCTION
02 ILLEGAL
DATA
ADDRESS
03 ILLEGAL
DATA
VALUE
1-6 Status
counter
Counter
Channel
Descriptions
Exception_Counter
W491
Keep a record of illegal request
RCV_Counter
W492
Keep a record of response sent
SND_Counter
W493
Keep a record of frame received
ER_RCV_Counter
W494
Keep a record of socket receive error
ER_SND_Counter
W495
Keep a record of socket send error