Rob Clark

This PC is a business computer that requires a company program load like CrowdStrike and all other kinds of nonsense so god knows what is going on in the background. Do you have another USB device that is not so dependent on a perfect world? It wouldn't take much memory on board a USB device to do most AO. My alternative right now is to ditch the Digilent stuff and find a waveform generator.

Under a year , maybe 6 months on one It's Windows 10 -- I put traces on all the data - driver reports all OK I now do a cbStatus while waiting for the ramp completion. On good ramps, status reports 0. On no ramps, fairly quickly error 78 (underrun) is reported. What causes this and is there a way to get around it?

I used the example as my starting point -- as I said it works sometime and not others

The following code attempts to output a ramp on a USB-231 or USB-234. At times the ramp occurs... other times, there is no output from the AO channel This is VB6 on Windows 10 using CBW32.DLL ver 6.73 lngStatus = cbDeclareRevision(CURRENTREVNUM) lngStatus = cbErrHandling(DONTPRINT, DONTSTOP) ' intWaveformArray >> array of voltages from 0 to 2 back to 0 converted to integer mccdevice.intBoardNum=0 mccdevice.intChannel=0 lngDownPoints=1000 lngCBRate=56 mccdevice.intRange=1 mccdevice.lngMemoryAddress = cbWinBufAlloc(lngDownPoints) lngFirstPoint = 0 lngStatus = cbWinArrayToBuf(intWaveformArray(0), _ mccdevice.lngMemoryAddress, lngFirstPoint, lngDownPoints) lngStatus = cbStopBackground(mccdevice.intBoardNum, AOFUNCTION) ' force to background so code can continue intOptions = BACKGROUND ' trigger the waveform output lngStatus = cbAOutScan(mccdevice.intBoardNum, mccdevice.intChannel, mccdevice.intChannel, _ lngDownPoints, lngCBRate, mccdevice.intRange, mccdevice.lngMemoryAddress, intOptions) Sometimes, restarting program the sequence will work fine. This occurs on both a USB-231 and USB-234. All statuses result in no errors but a voltage output does not occur. This module is ONLY used for AO, no other functions are used. As an aside, this code works fine with a PCI board.