34 lines
490 B
ArmAsm
34 lines
490 B
ArmAsm
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;;
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;; Official Kernal routine, described in:
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;;
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;; - [RG64] C64 Programmer's Reference Guide - page 283
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;; - [CM64] Compute's Mapping the Commodore 64 - page 227/228
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;;
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;; CPU registers that has to be preserved (see [RG64]): .X, .Y
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;;
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;; XXX currently does not preserve registers, to be fixed!
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getin:
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;; Wait for a key
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lda keys_in_key_buffer
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bne +
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;; Nothing in keyboard buffer to read
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sec
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lda #$00
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rts
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*
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lda keyboard_buffer
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pha
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jsr pop_keyboard_buffer
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pla
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clc
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rts
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