error occurs during DAQ and Motion Syncronization if timer event interval is <100 ms

[yancy]

In my CVI program, a second thread was created. In this thread, DAQ(PXI 6031E) scan was triggered by 7344 breakpoint output via RTSI, while in main thread's timer event callback function, axis position was read and interface updated. But when the program is running, I frequently encounter an error "-70025 NIMC_returnDataBufferNotEmptyError", and DAQ can not finish automatically. What results in this error? What should I do?

[Dustin_W]

This error is typically seen when commands are given to the controller before a previous command was finished. The controller is given commands in a "stack". As the controller completes commands it places results on a return data buffer, and fetches the next command. If this process is disrupted by giving the controller commands too quickly, or not retrieving data from the buffer quickly enough, the error you're getting can result. A couple things you might try, or at least investigate. Make sure that multiple threads are not sending commands to the board. Also in the latest version of the driver (ver 6.0) a lot of work was put into stopping that error, and you may find with that version the problem goes away.