Hello, I have project that includes Siemens IM 155-6 PN ST V4.2 IO node and communication with external HW using CM PtP module, and RDREC and WRREC functions from CommFB Library (by 3S). When serial communication is running by using RDREC and WRREC to access buffers of CM PtP I get error "CF81FD12 aborted: AR protocol violation", and after cca 3 seconds Siemens module gets back online. If I disable communication error is gone. I guess it has to do something with amount of Profinet communication but...