I am trying to use LabVIEW to write a program that will record the electrical responses of the eye to bright flashes of light. I've started to write the program by creating a simple function generator and passing a waveform from the computer, to one of the output terminals on my NI PCI 6024 DAQ Board, and then splitting the signal to an oscilloscope and back to an input channel on the DAQ board, which would then be displayed on the screen using LabVIEW. I am able to create the waveform function and it appears fine on the oscilloscope but not on the computer. At low frequency, the signal does appear on the computer screen but gradually drifts towards a value of 10 and then becomes saturated (i.e. the waveform becomes a horizontal
line at y = 10). At high frequency (~ 1kHz), the signal cannot be read by LabVIEW and I receive an error (# 10687). I've attempted connecting the cables to various input and output channels but always seen to see the drifting behavior. These drifting waveforms are also more variable from the original function generator waveform in that the amplitudes are significantly reduced (e.g. an amplitude 1 sine wave will have amplitude 0.7). If anyone has encountered similar problem and can suggest a possible solution or idea I could try, I'd appreciate it. Thanks.
