AXIOMTEK SBC8168, User Manual

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SBC8168 Socket 370 All-in-One CPU Card Series User’s Manual
Watchdog Timer 55
A p p e n d i x A
Watchdog Timer
Using the Watchdog Function
The SBC8168 CPU card uses version 2.0 of the watchdog
timer. This onboard WDT generates either a system reset or
non-maskable interrupt (NMI), depending on the settings made
on jumper
JP10 of SBC8168 . Follow the steps below to enable
and program the watchdog function of SBC8168 .
Start
↓
Un-Lock WDT : OUT 120H 0AH ; enter WDT function
OUT 120H 0BH ; enable WDT function
↓
Set multiple (1~4) : OUT 120 0NH ; N=1,2,3 or 4
↓
Set base timer (0~F) : OUT 121 0MH ; M=0,1,2,…F
↓
WDT counting
↓
re-set timer : OUT 121 0MH ; M=0,1,2,…F
↓
IF No re-set timer : WDT time-out, generate RESET or NMI
↓
IF to disable WDT : OUT 120 00H ; Can be disable at any time