I am using VirtexE to communication with an ADI's chip. The interface include, write, read, Data, and Address. I wish FPGA communication with the chip on FPGA main clock, which is up to 65MHz. I used a synchronized signal gated with the Clock to generate the write, read signal. Data and Address signal are synchronized. The problem is: 1) write/read signal often generate one more period than what I needed. although I could overcome it by adjust control signal's edge sensitivity, but it maybe reappear when I resynthesize the design. The reason is time delay of 2 inputs(one is clock, one is control signal) of the LUT4 vary greatly. Can I limit delay difference of the 2 inputs to an acceptable level? if it is, How could I do? 2) the timing of address, data and write/read is inconsistent with the timing required by ADI. I could delay some signal by add buffers or invertors. But I am afraid if it is work well if I add this modular to the top design. Is there any better way?
if I generate the w/r signal synchronized with the clock, the problem may do not exist. But I should drive the clock twice high, I don't know if VirtexE can work well on 125MHz.
Thank you for your advice.