Aaeon Compact Board PCM-9452, Manual

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C o m p a c t B o a r d P C M - 9 4 5 2
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
register)