This application has been working fine for a long period of time. Recently some DO's do not update on the last two channels. I am using an FP-2000 and a TB-10. I was getting an error from Automation Explorer saying that the socket was empty. I replaced with a new FP-DO-AC120 module and now it says success when I do a write, but the value does not change?
It sounds as though you may have some faulty hardware but you'll want to call into Customer Support to verify this. If your module needs repair, the Applications Engineer can help you isolate the problem.
Call 1-866-275-6964 and ask to speak with an engineer regarding a FP hardware malfunction.