57 lines
649 B
ArmAsm
57 lines
649 B
ArmAsm
.MACPACK generic
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.export _init, _nmi_int, _irq_int
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IRQ_CMD = $effc
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IRQ_DAT = $effd
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RTC_CMD = $effe
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RTC_DAT = $efff
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.zeropage
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finish: .res 1
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.code
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_nmi_int:
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_irq_int:
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lda #$6d
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sta finish
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_init:
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ldx #$ff
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txs
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; Enable irq0
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lda #$20
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sta IRQ_CMD
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lda #$01
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sta IRQ_DAT
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; edge type
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lda #$40
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sta IRQ_CMD
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lda #$00
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sta IRQ_DAT
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; Set increment
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lda #$10
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sta RTC_CMD
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lda #$01
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sta RTC_DAT
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; Set Threshold
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lda #$00
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sta RTC_CMD
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lda #$07
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sta RTC_DAT
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; Set IRQ Threshold
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lda #$20
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sta RTC_CMD
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lda #$02
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sta RTC_DAT
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cli
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wait:
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bra wait |