23 lines
294 B
ArmAsm
23 lines
294 B
ArmAsm
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// Pop key out of keyboard buffer
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// Disable interrupts while reading from keyboard buffer
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// so that no race conditions can occur
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//
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// CPU registers that has to be preserved: .X
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//
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pop_keyboard_buffer:
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ldy #$01
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sei
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!: lda KEYD,y
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sta KEYD-1,y
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iny
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cpy XMAX
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bne !-
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dec NDX
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cli
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rts
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