Hi, 

I'm using the MB_CLIENT on an S7-1200 to connect to an Swegon Gold AHU. When I start the PLC this work fine. But after a few hours the client stops, and the only way to restart it is to stop/start the PLC. The status is:

8380 "Received Modbus frame has incorrect format or too few bytes were received"

What can be wrong? Any help is appreciated

Hello,

be kind zip screenshots from your code to see how your system is working. Your code need have some checks/conditions to diagnose some situations and handle them correctly. Try check Help and STATUS,ERROR parameters.

It now stopped with the error status:

818B

The MB_DATA_PTR parameter has an invalid pointer. You should also check the values of theMB_DATA_ADDRand MB_DATA_LEN parameters.

 Hello,

AutoGen_4665985

It now stopped with the error status:

818B

The MB_DATA_PTR parameter has an invalid pointer. You should also check the values of theMB_DATA_ADDRand MB_DATA_LEN parameters.

 you point to some data area (DB or memory buffer) in MB_DATA_PTR and you set wrong value as address. Next Help sugestion is depended to register value you want access and for sure due DATA_PTR how much data you want exchange with server. All parameters are depended to each so you need check Help and see what your code does.