Watchdog Timer Configuration; Watchdog Timer Configuation - Kontron Mungo545 User Manual

Watchdog Timer Configuration

The function of the watchdog timer is to reset the system automatically
and is defined at I/O port 0443H. To enable the watchdog timer and allow
the system to reset, write I/O port 0443H. To disable the timer, write I/O
port 0441H for the system to stop the watchdog function. The timer has a
tolerance of 20% for its intervals.
The following describes how the timer should be programmed.
Enabling Watchdog:
MOV AX, 000FH (Choose the values from 0)
MOV DX, 0443H
OUT DX, AX
Disabling Watchdog
MOV AX, 00FH (Any value is fine.)
MOV DX, 0441H
OUT DX, AX
WATCHDOG TIMER CONTROL TABLE
Level Value
1
2
3
4
5
6
7
8
42
Time/sec
F 0
E 2
D 4
C 6
B 8
A 10
9 12
8 14
Level Value
9 7
10 6
11 5
12 4
13 3
14 2
15 1
16 0
Mungo545 User's Manual
Time/sec
16
18
20
22
24
26
28
30