What Can I Do in Case of Issues with Modbus IOScanner on Serial Line?
This section provides instructions that may help you to solve issues that were detected when using Modbus IOScanner on a Serial Line.
Exception State of the Application
A Modbus IOScanner on a Serial Line is configured on your controller and one of the Modbus slave devices is disconnected.
|
Step |
Action |
|---|---|
|
1 |
Verify the integrity of your cable. |
|
2 |
Verify that your cable is correctly connected between the controller and the Modbus Serial slave. |
|
3 |
Reset your controller. |
Error Detected While Using Modbus IOScanner on a Serial Line
|
If... |
Then ... |
|---|---|
|
an error is detected while using Modbus IOScanner on a Serial Line |
the xError flag associated to the slave that has been detected as generating or causing the error is set to TRUE. |
|
the communication is NOT stopped (the controller still tries to connect the slave). |
|
|
the parameter uiNumberOfCommunicatingSlaves is decreased and xAllSlavesOK is set to FALSE. |
After the communication to the slave has been re-established, a rising edge on the xReset entry of the slave is required:
oTo reset xError.
oTo update the values of uiNumberOfCommunicatingSlaves.
oTo update the values of xAllSlavesOK.
