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AAEON EPIC-5536 User Manual

Page 62

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E P I C B o a r d

E P I C - 5 5 3 6

Appendix A Programming the Watchdog Timer

A-4

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)

4

WDT output through PWROK1/PWROK2 (pulse) enable

3

Select the interrupt level

note

for WDT