[Open-graphics] How we compute video clocks

[Michael Meeuwisse]

On 5 Mar 2008, at 00:12, Michael Meeuwisse wrote:
> I don't think so. If I want to divide by 1, I keep on setting the  
> countdown to zero, thus essentially toggle the output every clock.  
> Divide by 4 sets the countdown to 2, etc. I did make a typo there,  
> the cases should be 1, 2, 4, 8, 16, 32, not 1 - 6.

It's late and I stopped thinking. That wasn't a typo.

On 5 Mar 2008, at 00:34, André Pouliot wrote:
> Actually to use the ClkFx output with a frequency input below 18MHz  
> there shouldn't be any feedback present on the dcm.
>
> For the documentation it's in the document ds099.pdf page 88 table  
> 59 for the timing specification for the Digital Frequency synthesizer.

I'm sorry, I don't follow. I don't see it saying anywhere that CLKFB  
shouldn't be connected.

Cheers,

Michael
www.projectvga.org

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