Intel PCM-9452 ,

Compact Board PCM-9452

Appendix A Programming the Watchdog Timer A - 4

Configure Control (Index=02h) This register is write only. Its values are not sticky; that is to say, a hardware reset will automatically clear the bits, and does not require the software to clear them.

Bit Description

7-2 Reserved

1 Returns to the Wait for Key state. This bit is used when the

configuration sequence is completed.

0 Resets all logical devices and restores configuration registers

to their power-on states.

WatchDog Timer Control Register (Index=71h, Default=00h)

Bit Description

7 WDT is reset upon a CIR interrupt

6 WDT is reset upon a KBC (Mouse) interrupt

5 WDT is reset upon a KBC (Keyboard) interrupt

4 WDT is reset upon a read or a write to the Game port base

address

3-2 Reserved

1 Force Time-out. This bit is self-clearing

0 WDT status

1: WDT value reaches 0

0: WDT value is not 0

WatchDog Timer Configuration Register (Index=72h,

Default=00h)

Bit Description

7 WDT Time-out value select

1: Second

0: Minute

6 WDT output through KRST (pulse) enable

5 WDT Time-out value Extra select

1: 4s.

0: Determine by WDT Time-out value select (bit7 of this