some procblem about delay

At 50MHz, you need it to delay it by 1600 clock cycles, using a large shift register.

Depending on the width of your data stream, that may require quite a bit of resources.

I suggest you use the ALTSHIFT_TAPS function, so the shift register is implemented in RAM.

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Thank you very much! I think that is a way, however it require so much resources.

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Yes. if its too many resources either:

1. redesign your system so you dont need such a large delay

2. get a bigger chip

3. Use an external ram.