looking for quick ideas to synchronously start multiple counters on PXI-6608 at zero in a countdown from (T = -15 to T = +10)

[rocketball]

I need to synchronously start multiple counters on the pxi-6608 within a countdown in labview. I will press a start button to initiate countdown. The 6608 will be synched with irig-b. I have gps reciever and I am able to get irig-b into labview for display. I also want to capture the irig-b time when countdown reaches zero and starts the counters. The countdown will continue 10 seconds after zero.

[JustinBritten]

You did not specify what you are synchronously starting multiple counters to do; however, most counter applications can be programmed to start upon receiving a hardware trigger. In order to hardware trigger multiple counters at a given GPS time we can use an example that has been written called "GPS Alarm Clock.llb." This example will generate a pulse at a user-specified time. In your case the user-specified time is 10 seconds from the current time. You will have to slightly modify this example such that the user-specified time is not entered on the front panel, but instead, calculated in software as the current time plus 10 seconds.

Synchronizing and Correlating Measurements to a Global Timebase with GPS
http://zone.ni.com/devzone/conceptd.nsf/webmain
/2FAD3B4E67BA766186256B9C00679F75?opendocument

If you look at the end of the document and expand "How to Program the PXI-6608 with GPS in LabVIEW" then you will see the example I am referring to. Furthermore, if you expand "Generate Trigger at User-Specified Time" you will see an explanation of how this VI works.

Regards,
Justin Britten

Applications Engineer
National Instruments