Hi, 

Am using CPU 317-2PN/DP as Modbus TCP Client. Am facing problem, the Done & Error bits are not working in the user program, because i need to increment the counter to poll the slave devices. While monitoring on VAT the bits are getting ON/OFF but not working on user program. The program backup enclosed for reference.

Please advise to resolve.

Thanks,

Dina 

Hi,

in your OB1 programm you have a "BEU" statement (Block End Unconditional) in line 74. It will end the cycle in case the Modbus block returns a done.

Can you replace it with a "JU end" (Jump Unconditional) and see if it works?