JAZZ_IO_IRQ_ENABLE
mask |= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
mask &= r4030_read_reg16(JAZZ_IO_IRQ_ENABLE);
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, mask);
r4030_write_reg16(JAZZ_IO_IRQ_ENABLE, 0);