PIT_MODE
outb_p(0x34, PIT_MODE); /* binary, mode 2, LSB/MSB, ch 0 */
outb_p(0x30, PIT_MODE);
outb_p(0x30, PIT_MODE);
outb_p(0x38, PIT_MODE);
outb_p(0x34, PIT_MODE);
outb_p(0x00, PIT_MODE); /* latch the count ASAP */
outb_p(0x34, PIT_MODE);