Gameboy/interrupt.c at master · sacert/Gameboy · GitHub

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#include <stdio.h>
#import "interrupt.h"
#import "cpu.h"

struct interrupt interrupt;

void interruptCycle(void) {

    if (interrupt.pending == 1) {
        interrupt.pending -= 1;
        return;
    }

    // if everything is enabled and there is a flag set
    if (interrupt.master && interrupt.enable && interrupt.flags) {
        // get which interrupt is currently being executed
        unsigned char inter = interrupt.enable & interrupt.flags;

        if (inter & VBLANK) {
            interrupt.flags &= ~VBLANK; // turn off the flag
            cpuInterrupt(0x40);
        }

        if (inter & LCDSTAT) {
            interrupt.flags &= ~LCDSTAT;
            cpuInterrupt(0x48);
        }

        if (inter & TIMER) {
            interrupt.flags &= ~TIMER;
            cpuInterrupt(0x50);
        }

        if (inter & SERIAL) {
            interrupt.flags &= ~SERIAL;
            cpuInterrupt(0x58);
        }

        if (inter & JOYPAD) {
            interrupt.flags &= ~JOYPAD;
            cpuInterrupt(0x60);
        }
    }
}