[Coco] Assembly code scans keyboard but doesn't repeat

Dave Philipsen dave at davebiz.com
Mon Mar 6 18:42:42 EST 2017


But then you should really de-bounce it too....

Dave


On 3/6/2017 5:22 PM, Mark McDougall wrote:
> On 7/03/2017 9:28 AM, Glen Hewlett wrote:
>
> If you save the previous column scan byte, and then XOR it with the 
> new column scan byte, then any change of state will be indicated by a 
> '1' bit in the result. If you then AND that with the complement of the 
> new byte, then a '1' bit means the key has just been pressed (aka 
> rising-edge detect).
>
> At least that works in my head right now. ;)
>
> Regards,
>



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