how do i generate the TTL pulse from PCI 6024E DAQ card

[Amir A]

Hi, I'm trying to write a program which generates a single TTL pulse when it is run. My goal is to generate the pulse, send it to the output channel of my PCI 6024E DAQ card, and then use a BNC cable, to display the signal on the oscilloscope. I have written the code and I think it appears fine but when I try to view the signal on the scope I am unable to see the pulse. I have tried slowing down the sweep on the scope and have adjusted the voltage and time scales but have not seen any response. After examing my DAQ card, I noticed that none of the PFI/TRIG terminals on the card are wired; the output channel connects to terminals for DAC0OUT and Ground. I'm wondering if this pin needs to be wired in orde
r to generate the pulse since PFI0/TRIG1 is the start trigger terminal. Any help would be appreciated. Thanks.

[Russell]

For your code, you shouldn't have to worry about the PFI-/TRIG1 or DAC0OUT lines. The output of the counter will show up on the GPCTRx_OUT pin. (Where x is either 0 or 1 depending on which counter you choose.)

If you want another test you can do just to verify you can see the board generate pulses, go the the MAX test panel and generate a pulse or pulse train on one of the counters. The test panel can be found by right-clicking on your board from the list under "Devices and Interfaces," and selecting "Test Panel."

Russell
Applications Engineer
National Instruments
http://www.ni.com/support

[Amir A]

Hi Russel,

Thanks for your response. Since the GPCTRx_OUT, GPCTRx_SOURCE, and GPCTRx_GATE pins on my card are not wired to a terminal on which I could connect my BNC cable from the box to the oscilloscope, I assume this would explain why I can't view the signal. As such, I'd probably have to contact the technician who wired my board and have him wire the counter output pin to one of the terminals to which I could connect my BNC cable. I presume I could use MAX to test whether the board is generating pulses even if the counter pins are not wired?