[Coco] Assembly code scans keyboard but doesn't repeat
Mark McDougall
msmcdoug at iinet.net.au
Mon Mar 6 18:22:14 EST 2017
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,
--
Mark McDougall
<http://retroports.blogspot.com.au>
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