The maximum update rate on the DI-300 is 1kHz. Running the FP-2000 at 100us is probably a bit to fast for that controller. The first thing RT will do when you are running at high CPU is not handle any communications (including the default communication) this will make it look like the RT has crashed or locked up.
SteveA
CLD
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FPGA/RT/PDA/TP/DSC
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