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Altera_Forum
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20 years ago

Correct procedure for changing the clock speed

The Timing Analyzer reports that my fmax is 70MHz. So if I want to run at 70MHz, is this what I do? 1) In SOPC Builder, change clk to 70.0, then regenerate. 2) In the sdram_pll, change the in...
Altera_Forum's avatar
Altera_Forum
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20 years ago

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originally posted by bkucera+mar 22 2006, 11:39 am--><div class='quotetop'>quote (bkucera @ mar 22 2006, 11:39 am)</div>

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<!--quotebegin-kalle leo@Mar 22 2006, 04:12 AM

have you also set the input clk for your system to 70mhz?

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No, how do I do that?

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I&#39;m not so sure if that is necessary.. you have an oscillator running at "X" which has not changed. You need to tell the PLL wizard what this input frequency "X" is... then to adjust your actual system clock speed, either tell the PLL wizard which output freq you want, or play with the multiplier/divisor numbers to get the desired output.