Thank you for your helpful response.
Is it possible to feed back the CO or O output into the LUT of the same slice, and then connect the output of the LUT to the DI input of the same CARRY4? (with local routing)
What is your suggestion for redesigning the TDC to avoid using feedback?
I need to implement two delay lines for a Vernier TDC. I plan to use CARRY4 for both lines. As you know, the delay of the first line must be slightly longer than the second one. What do you suggest to increase the delay in the first line?
My idea was to use internal XOR gates within the CARRY4 of the first line by creating some feedback to add extra delay. But it doesn’t seem to work, and now I’m not sure what to do.