[Coco] CoCo's TIMER and 60hz

[Dave Philipsen]

I’m pretty sure the timer itself is driven by the same crystal that generates the video timing in a real CoCo. In my mind, the solution is just to write a driver that corrects for the clock variance.

Dave

On May 29, 2019, at 8:16 PM, Allen Huffman <alsplace at pobox.com> wrote:

>> On May 29, 2019, at 7:47 PM, Bill Nobel <b_nobel at hotmail.com> wrote:
>> 
>> Allen, Roger sent me the test build which puts VSYNC on a pin I can test.  On power-up the rate comes back at 59.64 Hz. The moment I switch into double height in Nitros9 EOU it jumps to 60.11 Hz.  Roger is now working to get the lower res 32 column screen a bit better on the clock, but even if he does it still will be a bit off.
> 
> Are there other IRQ sources we can use for a Matchbox clock driver?
> 
>       — Allen
> 
> 
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