[Coco] strange behaviour
Roger Taylor
rtaylor at bayou.com
Wed Jun 16 15:03:40 EDT 2004
At 07:15 AM 6/16/2004, you wrote:
>On 15-Jun-04, at 10:59 PM, Roger Taylor wrote:
>
>>The only place you seem to be setting ___ungetched_char is when you clear
>>it with clra/sta, yet you're checking it for a character upon entry into
>>the code.
>
>That part, believe it or not, is correct. It gets set elsewhere, in
>another assembly routine. The part that really seems to be giving me
>trouble is this:
>
>read_key:
> jsr [0xA000] ; call POLCAT
> beq read_key
>
>where the routine will stay in a loop even if I press a key. The BASIC
>manual says that Z will be 1 upon finding no key pressed, but 0 if it is
>pressed. But my code doesn't seem to be reacting that way.
Just replace that with jsr [40960] and see what happens. There's also a
STDIN/STDOUT variable at address 111 that should be set to 0 for the
screen/keyboard. I'm not sure about STDIN but I know that this is the
STDOUT variable address.
And then, where is the code that sets ___ungetched_char with a
keycode? You're checking ___ungetched_char for a keycode at the top of
your routine. How and where is this variable getting set???
----------
Roger Taylor
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