37 lines
573 B
ArmAsm
37 lines
573 B
ArmAsm
; Timer that's incremented every 64 cycles
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; Initializes timer for use by sync_tima_64
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init_tima_64:
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wreg TMA,0
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wreg TAC,$07
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ret
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; Synchronizes to timer
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; Preserved: AF, BC, DE, HL
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sync_tima_64:
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push af
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push hl
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; Coarse
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ld hl,TIMA
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ld a,0
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ld (hl),a
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- or (hl)
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jr z,-
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; Fine
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- delay 65-12
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xor a
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ld (hl),a
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or (hl)
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delay 4
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jr z,-
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pop hl
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pop af
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ret
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; Read from this to get count that's incremented
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; every 64 cycles.
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.define tima_64 TIMA
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