2019-09-27 07:38:51 +00:00
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;
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2020-01-10 20:17:23 +00:00
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; 2020-01-08, Greg King
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2019-09-27 07:38:51 +00:00
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;
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; unsigned char kbhit (void);
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; /* Returns non-zero (true) if a typed character is waiting. */
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;
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.export _kbhit
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.include "cx16.inc"
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.proc _kbhit
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2020-01-10 20:17:23 +00:00
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ldy VIA1::PRA ; (KEY_COUNT is in RAM bank 0)
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stz VIA1::PRA
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2019-09-27 07:38:51 +00:00
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lda KEY_COUNT ; Get number of characters
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2020-01-10 20:17:23 +00:00
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sty VIA1::PRA
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2019-11-16 18:11:40 +00:00
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tax ; High byte of return (only its zero/nonzero ...
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2019-12-25 15:56:32 +00:00
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rts ; ... state matters)
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2019-09-27 07:38:51 +00:00
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.endproc
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