src/interrupts.s


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.segment "FIXED"

.proc nmi
    pha
    txa
    pha
    tya
    pha

    ;; Sprite DMA.
    lda #$00
    sta OAM::m_address
    lda #$02
    sta OAM::m_dma

    ;; TODO

    ;; Always reset the scroll just in case.
    bit PPU::m_status
    lda #$00
    sta PPU::m_scroll
    sta PPU::m_scroll

    ;; Restore registers.
    pla
    tay
    pla
    tax
    pla

    rti
.endproc

;; Unused.
.proc irq
    rti
.endproc