PIC_MASTER_MASK
out8(in8(PIC_MASTER_MASK) & ~(1 << num), PIC_MASTER_MASK);
out8(in8(PIC_MASTER_MASK) | (1 << num), PIC_MASTER_MASK);
out8(0xfb, PIC_MASTER_MASK); // Mask off all interrupts (except slave pic line IRQ 2).
enabledInterrupts = ~(in8(PIC_MASTER_MASK) | in8(PIC_SLAVE_MASK) << 8);
out8(0xff, PIC_MASTER_MASK);
#define PIC_MASTER_INIT2 PIC_MASTER_MASK
#define PIC_MASTER_INIT3 PIC_MASTER_MASK
#define PIC_MASTER_INIT4 PIC_MASTER_MASK