Forum Discussion

Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

how to constrain low frequency clocks

Hi, everyone! Again I encounter some problems in constraining very low frequency clocks. I have a 15MHz input clock, then generate a 400Hz clock through counters, and further generate 10...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

--- Quote Start ---

I suggest you lie about those clocks with very low frequencies and constrain them as if they had frequencies within TimeQuest's allowed range.

TimeQuest will allow for clocks as low as 100 kHz (at least).

--- Quote End ---

Hi,

the suggesttion of rbugalho is a good one. There should be no clock speed problems occur, but Quartus will check setup and hold times.

Kind regards

GPK