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Altera_Forum
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19 years ago

To Nios II/s or f processor speed

Hi all, During building Nios II/standard or Nios II/full_featured, I have used the clock at 50MHz. According to Altera, the Stratix pro board will have 200 DMIPS speed with 1.17...
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Altera_Forum
Icon for Honored Contributor rankHonored Contributor
19 years ago

Hi Goutam,

Jakob has given excellent advice but if your design doesn't reach the required Fmax there may be a few tweaks that you can try before having to compromise your design.

The Timing Advisor gives good advice.

Also, under 'Analysis & Synthesis Settings' there is a optimisation for speed/balanced/area. When I was struggling with my Fmax an Altera field engineer suggested setting 'balanced' instead of 'speed'. Surprisingly, this did increase my Fmax.

Changing the 'seed' value in the 'Fitter Settings' will also alter the Fmax - sometimes faster, sometimes slower.

In my design, none of the above have much more than about a 20% gain in speed. If you want 200MHz and you currently have Fmax of around 70MHz then Jakob is right - forget it. If your Fmax is 150MHz then it might be worth playing with SOPC for a while first.

Good luck.

Banx.