thoult

Sorry, forgot that might help I'm running a National Instruments PCI 6251 card on a P4 2.8 Ghz with 512 MB RAM. Fundamentally my VI works - I can connect my DAQ to a National Instruments ELVIS prototyping board and measure the voltages produced across the DAC0 and DAC1 pins. Eventually however, I get that error message and I have to use Task Manager to stop Labview running. From then on, every time I open that instance of the VI, it will give me that error message straight away. I can save the VI in another location, run it, and after a short while it will give the same error. If I remove one set of the DAQmx commands then it will run continuously to its heart's content. The critical error only occurs when I try and send voltages to both AOs.

Hi, I'm relatively new to Labview, and am using 7.1 to create a control system for DC motors. My VI consists of two parts - the logical part, which determines the magnitudes of the external voltages, and the hardware driving part which allows me to use my DAQ's two analog output channels. The second part consists of essentially the contents of the Gen Analog Voltage Update.vi example - DAQmx Create Channel (AO-Voltage-Basic), DAQmx Write (Analog DBL 1Chan 1Samp) and DAQmx Clear Task VIs. When I first ran my instrument, it returned an error telling me their was a conflict with parameters - I attributed that to having copy and pasted the AO tasks from the example VI. After rebuilding each task from scratch, the instrument would run, only to crash after a few runs, returning the following error message: "An exception occurred within the external code called by a Call Library node. This might have corrupted Labview's memory. Save any work to a new location and restart Labview." I read elsewhere that other users have had similar problems when using more than one output channel simultaneously. If any of you have any ideas, I'd be grateful to hear them. I can post my VI or a screencap if that helps too.