Outputing 25mhz using counters
Harrison.
Posts: 484
Can a Propeller running at 80mhz (5mhz xtal + 16pll) generate a stable 25mhz output using the built in counters? I read in another post that the synthesized frequency should be a multiple of the main clock signal. Unfortunately I don't know what else is required to generate a stable frequency so I am asking this question.
I am asking this because I am going to try to write an extremely limited tcp/ip stack using the Propeller and a ENC28J60 ethernet chip from Microchip. This chip requires an accurate 25mhz clock source in order to generate correctly timed ethernet signals.
Harrison
I am asking this because I am going to try to write an extremely limited tcp/ip stack using the Propeller and a ENC28J60 ethernet chip from Microchip. This chip requires an accurate 25mhz clock source in order to generate correctly timed ethernet signals.
Harrison
Comments
If I did the math right you would load the FRQx register with $1400_0000 which would give you 6.25 MHz (with an 80MHz clock), then use the x4 PLL to get 25MHz exactly.
Bean.
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