Hello,

good luck, do all recommended steps and you can have good results. No problem with next help but save some screenshots with tests you'll do for better next support. You can then post them in ZIP file attached and with your description.

Hello,

more tips.

1. at TRCV block I expect same pointer to same place every time to store.

2. use of ADHOC true definitelly, for more info check TIA Help. This is best way to work with different length messages received in my opinion.

3. it is possible to leave TRCV in EN_R true permanently after establish connection to Server (Reader), do tests.

try that ADHOC as test. Really from my experience many years, this system gives me best results. It is not only about how much data you will receive everytime. Simply I expect after you check programatically that TRCV NDR/DONE is true (data received) you can then check what is inside buffer. Don't send any other data. Try manage send only for tests via manual set REQ and reset it after DONE or ERROR is true. Doing complex flow of code and communication settings is hard to solve for first attempts. I do everytime manual sends with receive, then check and if all possible messages are ok as receive data then will do some state machine or other steps what I need. Did you check your messages without PLC and with some PC application like Hercules? You'll then easy see if all received data are consistent as you require. Without ADHOC is simple rule, if your receive message isn't full of expected length as is defined, then it will not ends and you will not have NDR/DONE with TRCV in true. Your situation looks to me like this, your receive data are mixed. Try check conditions depended to receive and check receive buffer/DB.