DAQCard 1200: How can I send two TTL singals on separate channels with adjustable delay shortly after (typically a few milliseconds) external triggering?

Question

Hi, this is probably a simple question, but I have never used the digital and timing part of any DAQboard before... I wish to use an old Power Macintosh 7200 with a DAQCard 1200 for timing and synchronizing external events . The scenario is as follows; an external device (in my case; a CCD camera) sends a trigger signal (TTL, 600 ns). I want this signal to trigger the DAQCard, whereafter I want the DAQCard to send two TTL pulses (20 microsecond duration) from two separate channels (one pulse from each channel). The first pulse must be sent within a few milliseconds after the trigger is recieved. Th
en I wish to be able to control the delay from the first pulse is sent and to the second pulse. This delay should preferably be adjustable from a few microseconds and up to at least 20 milliseconds. How can I achieve that kind of operation? (I need a few tips to get started.. like for instance: should I connect the external trigger signal to the EXTTRIG pin or to the gate pin of one of the counters? Do I have to interconnect the counters in some way? Do I have to invert the OUT signals? etc..)Thanks for your help in advance.
regards,
Michal

Answer 1

I have not personally used the DAQCard 1200, but if it is similar to the E-series devices, you route the trigger signal to the gates of both counters.
In your code, use the Data Acquisition->Counter->Generate Delayed Pulse VI twice, once for each counter. You can then set an input on that VI to select to trigger on the gate, and set the delay and pulse width of the pulse. Since both will start from the same trigger, you can delay either pulse as long as you wish, from microsecond to seconds, making the second pulse follow the first.
Mark