I am experiencing random, but easily reproducible freezups of my XPc target when communicating using Quatech QSCLP-200/300 and QSC-100 PCI serial boards. Using Matlab 2009b. The XPc target becomes unresponsive (freezes screen and keyboard and stops communicating via TCP/IP and serial) at random times (somewhere between 1 and 3000 sec of simulation time).
I am running a very large aircraft simulation model (>100,000 Simulink blocks) that uses serial communication at 50 Hz in and out. The amount of data transferred is not that large at this point ( < 300 bytes ). When I run this model with serial communication blocks removed, it runs normally.
The symptomology is very subtle, and to make things worse, once I switch to using RS 232 baseboard com ports, I cannot reproduce the problem.
I tried to run the model on two different XPC boxes with similar configurations. I tried different cards, interrupt configurations, etc. Problem persists.
I am failing to reproduce the problem on a smaller model subset. I tried to extract just the com piece that does RS 422 uplink, downlink and data packaging, and the problem goes away.
I suspect some sort of PCI bus/hardware conflict that has to do with timing, but so far cannot seem to pinpoint it. I should probably also mention that I am using a PCI ethernet card and broadcasting some UDP packets out of XPC occasionally. Tried to remove it as well to eliminate the cause, but problem still persists.
Any idea how I could go about diagnosing/debugging the problem? I would love to isolate it to a smaller model subset that I can share with Mathworks tech support, but so far I cannot seem to do that. Something to do with model size.
Any thoughts are appreciated.
Nikita
