my programme uses PCI-6533 and PCI-6229 to aquire data. Port 0 of 6533 generate digital pattern at 1.2Mhz, port 1 of 6533 samples this pattern synchronistically. when the programme receives a start signal, it runs a time. At first it can runs normally. But after several hundreds times, the programme halts. The abort button can't stop it. How resolve this problem? my labview is 8.2, DAQmx is 8.3.1. Thanks