03-20-2012 02:02 PM - edited 03-20-2012 02:03 PM
Hi,
I have some experience with Quartus, but new to the NI FPGA.
I have a PCI-7811R. I am trying to use it to sequentially light up 144 LEDs repetitively. The period of each pulse is 480us.
Basically, I need to generate a pulse generator and a counter to record the pulse number, and according to this number, select which LED is on.
I designed a pulse train generator based on a example from FPGA help, and added a counter in it. You can see it in the attached vi.
My question is,
When I put the I/O node inside the single-cycle timed loops, it can generate the correct pulse. However, when I tried to use the local variable to transfer data out of the SCTL, and then connect it to another I/O node, I cannot detect the pulse signal when I measured this I/O.
Is there something wrong with my code when I try to transfer data out of the SCTL? Can I also use local variable to transfer the counter value, because I will need it in the following part.
Thank you!
Solved! Go to Solution.
03-20-2012 03:02 PM
If you're referring to the local variable wired to DIO2 in your attached VI, the problem is very simple: it's outside a loop, so it only executes once. Put that local variable and the IO node in a loop and I think you'll get something close to the pulse you expect (although if it's not in a single-cycle loop you may not get exactly the same timing).