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Write commands to GPIB with precise timing (clearer)

I would like to write a command to the GPIB card several times, the time interval between two writings must be very precise(<1ms). This time interval includes two parts, one is the time GPIB communicates with the instrument(Function generator without external trigger for F.M.), another is the software delay time.Both are not precise enough.My idea is to hardware delay a time interval and at the begining of the delay, write a command to GPIB simultaneously.So the time GPIB communicates with the instrument is covered by the precise hardware delayed time(An illustration is on the attached file).I don't know that whether the hardware delayed time can be generated by my PCI-6713 and PCI-6602 and whether I can write
a command to GPIB at the begining of the delayed time. Any suggestion?
Thank you for your kind help!!
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The only solution that I could see here would be to build a latch on the GPIB lines that would release a signal when the hardware delay triggers it. All done in hardware. The timing from a Windoze machine is never precise. From the time your software commands to send a GPIB message until it is actually on the GPIB lines can be anywhere from 2ms to 50ms just based on the "multitasking" from Windoze (not taking any delay from the GPIB card into account).
To get that accuracy in your program, you need LabVIEW RT and some expensive hardware. Someone else could help you on that end. Maybe talk to your local NI rep.

Rob
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if you just need to coordinate an event on your func gen with some sort of measurement hardware, spend the 1500 and get a generator with triggering (agilent 33120A for example).
There must be some existing hardware solutions you can buy for less than building your own (remember to count your time in the cost of the project).
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