Return bus communication error count (sub-function code: 0CH)
Operation description
Reads out the number of error messages detected on the line to the master.
Request message format (from master to slave)
Function code
Sub-function code
08H
(000CH)
(H)
Response message format (from slave to master)
■ When completed successfully
Function code
Sub-function code
08H
(000CH)
(H)
Returns the count value of the buffer memory listed below to the master.
• 'Bus communication error count' (Un\G32513/Un\G32577)
Refer to the following for the counter descriptions, count range, and count clear methods.
Page 21 Checking communication conditions using a diagnostic counter
■ When completed with an error
Function code
Data
Exception code
88H
Data
(0000H)
(L)
(H)
(L)
Data
Bus communication
error count value
(0000H to FFFFH)
(H)
(L)
(L)
3 MODBUS STANDARD FUNCTION DETAILS
3.8 Diagnostics (FC: 08H)
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