FPGA

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I have one method of using a counter. The formula for calculating the counter is ( Actual Frequency / required frequency)

use that as the set point for your counter and make use of this code(This IS for 26MHz from 100MHz clock, so the Count value WilL be(100m/26M = 3.)

  • if (clock = '1' and clock'event ) then
  •      if ( count /= 4)
  •       count := count + 1 ;
  •       clock_out := clock_out ;
  •        else
  •         count := 0 ;
  •           clock_out := not clock_out ;
  •     end if;
  • end if ;

so for 13MHz the count value will be 7