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General • Re: Changing clk_sys divisor causes long delay

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one thing that comes to mind, is the direction of the change

if we assume that internally, the divisor is implemented with just a counter and a == test
and lets say its set to /5 and the count is 4, and you change it to /1
then it will miss the ==5 test, and you just wont get another clock cycle until the counter rolls over

and its a 24bit integer component to the divisor, so that will cause up to 16,777,216 clock cycles of extra delay, any time you reduce the divisor

Code:

> Math.pow(2,24) / 1250000000.134217728
which comes out to about 134ms if the input is 125mhz

Statistics: Posted by cleverca22 — Sun Jun 08, 2025 3:42 am



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