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Altera_Forum
Honored Contributor
16 years agoClock Hold warning
Hello friends, I have complete and simulate some design for MAX3000A. I have one warning I cannot avoid Warning: Can't achieve minimum setup and hold requirement clock_in along 8 path(s)...
Altera_Forum
Honored Contributor
16 years ago --- Quote Start --- Thanks pletz (and all), finally solved. It was my faulty design (mixed schematic and verilog). Basically I was trying to do several consecutive operations on the same posedge. I create a tmp reg variable and then use it to copy desired data @ unused negedge of master clock. Now everything is in verilog. I guess LCELL delay was anyhow a compromise sollution that should be avoided. I'm not clear with fast timing analysis you said. I have run Classic Timing Analysis and everything is ok from 1KHz to 10MHz. Actually it reports somewhere around 29MHz limit on my design (portions) which is anyhow far enough for me. This is a transcoder from serial stream (synchron) to parallel bus and vicecersa (bidir) up to 153Kbps. --- Quote End --- Hi, did you solve your hold time problems ? As default the classic timing analyzer uses the worst-case parameter, means slowest process, low power supply and high temperature. You have to check the hold time also with the fast parameter to be sure that it works also. You can run a fast timing analysis : Processing -> Start -> Start Classic Timing Analyzer (Fast Timing Model) Kind regards GPK