Programming - Aaeon HSB-668I Manual

H a l f - s i z e C P U C a r d
A.1 Programming
An onboard watchdog timer reduces the chance of
disruptions which CPLD (Compact Programmable Logical
Device) interface can cause. This is an invaluable protective
device for standalone or punmanned applications. When the
watchdog timer activates (CPU processing has come to a
halt), it can reset the system, or generate an interrupt on
IRQ10, IRQ11, IRQ15, and NM1. This can be set via I/O Port
444, the function as following:
0: RESET
1: NM1
2: IRQ10
3: IRQ11
4: IRQ15
If you decide to program the watchdog timer, you must write
data to I/O port 443 (hex). The output data is a value timer.
You can write form 01 (hex) to FF (hex) while simultaneously
setting it. When you want to disable the watchdog timer, your
program should read a Hex value from I/O port 80 (hex).
The following procesude is a sample program for the
watchdog timer:
The time interval data of the watchdog timer is shown in
binary code (8 bits).
Sample 2: 5 seconds
Appendix A Programming the Watchdog Timer
Type C:\DOS\Debug <ENTER>
To start watchdog timer and set function "Reset"
type; o 444 0<Enter>; out 444h data 0
To input Watchdog timers time-out interval of 5
seconds type; o 443 05<Enter>; out 443h data 05
To disable the watch timer type; i80 <Enter>
0 0 0
H S B - 6 6 8 I
0 0 1 0
A-2
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