Forum Discussion
Altera_Forum
Honored Contributor
11 years agoDynamic adjustment of Cyclone III IOE Programmable Delay?
Hi, is it possible to adjust the Cyclone III IOE delay at runtime, or only at bitstream generation time? In particular, the i/o buffer megafunction (altiobuf) user guide (http://application-not...
Altera_Forum
Honored Contributor
11 years agoThe forum has done something very strange and deleted my post but didn't delete the thread! Here is what I wrote:
Sorry for the double-post, but the forum is doing really strange stuff with my threads. The previous thread I started has zero postings (not even my own!). Did a moderator delete my post but not delete the thread? Sorry if I did something wrong... Anyways: Is it possible to adjust the Cyclone III IOE delay at runtime, or only at bitstream generation time? In particular, the I/O Buffer Megafunction (ALTIOBUF) User Guide for StratixIII+CycloneIII says that it is possible, but all the examples use the StratixIII-specific StratixII_CONFIG_IO primitive, which doesn't work on CycloneIII (or is there some trick that makes it work?). According to the Cyclone III datasheet the input-pin-to-register and output-register-to-pin delay lines have a range of 0ps to 1000ps or more, but I need to be able to adjust this on a per-board and per-pin basis, so the values aren't known at the time the bitstream is written. I need to be able to sweep the values while checking error rates, similar to how the PLL output phases can be adjusted in real time.