I have a bug and it seems to manifest itself only in stealth mode. When I move my LEDs to see what the trouble is, the bug goes away.
I am using Xilinx XST v7.1, a ML403 dev board, and the issue seems to happen during powerup. A certain action freezes and Reset does not help. Timing is being met.
I would like to add LEDs to debug the problem without there changing the circuit as little as possible. Is there a way to do this with incremental design change and how do I do that? Can I nail all the logic to the same LOCs? Is there a TIG-like constraint that would act from the LED output backwards toward the source?
Thanks,
Brad Smallridge Ai Vision