09-29-2008 02:45 PM
This soudns a little silly to ask becuase I know FPGA is all about transistor logic...but I would like to create have an event in software triggered by an external Digital trigger. Im my host I have an event loop running and I don't really want to use the "timeout" feature to "poll" for the digital line. I wanted to know if I use the FPGA to look for the digital and when it changes ont he rising edge maybe set a variable high that trigers a user event??
Any ideas or suggestions?
Thanks
09-30-2008 02:25 PM - edited 09-30-2008 02:28 PM
DAK_Trap:
Check out the example finder for a great example of what you are trying to do, this is written for a cRio, but you should be able to port the code over if you are using an R-series board:
Help->Find Examples-> Hardware Input and Output-> Compact Rio -> FPGA Fundamentals -> Triggers and Watchdog -> 'Trigger Detection - Software - cRio.lvproj'
Also attached a screenshot in case you can't find that example ![]()
Be careful firing events programatically, they are really designed to be triggered by front panel actions. You should be able to just poll the variables until a change is detected, and then execute whatever code you are waiting on.