31 lines
288 B
ArmAsm
31 lines
288 B
ArmAsm
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//
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// Well-known Kernal routine, described in:
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//
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// - http://sta.c64.org/cbm64kbdfunc.html
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//
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read_kb_buf:
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// Check for a key
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lda NDX
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bne !+
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// Nothing in keyboard buffer to read
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sec
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rts
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!:
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lda KEYD
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pha
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phy_trash_a
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jsr pop_keyboard_buffer
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ply_trash_a
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pla
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clc
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rts
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