Hello Matthew,
It appears there may be some confusion about our M Series DAQ. The USB-6251 can only do standard TTL logic, which is 0-5V. In order to do the 24V digital logic, you will need a high voltage Digital Output device. This narrows down the choices quite a bit. By looking at our
USB Digital I/O Product Selection Guide, it appears that to attain the output voltages you require, the
9472 is the way to go.
If you want to do a finite
pulse train. If this is the case, then you will need 2 counters to accomplish this. I believe that if you use the
cDAQ 9172 Chassis, there are two counters available from slots 5 or 6. If the timing for the trigger is not essential, then you could just do this programatically instead of using the counters. One thing to note about this setup, you will need a pulldown resistor for the "low" state.
Here is a Knowledgebase about that.
I hope this helps.
Neal M.
Applications Engineering National Instruments www.ni.com/support