Aaeon SBC-860, Руководство пользователя

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F u l l - s i z e C P U C a r d S B C - 8 6 0
Appendix A Programming the Watchdog Timer
A-2
A.1 How to program the watchdog timer
SBC-860 utilizes ITE 8712 chipset as its watchdog timer controller.
Please follow the procedures below to complete its configuration.
1. Enter the MB PnP mode
2. Select logical device
3. Configure the watchdog timer controller registers
4. Exit the MB PnP mode
To enter the MB PnP mode is to write value 87h, 1h, 55h, 55h to
configuration port - 2Eh.
To exit the MB PnP mode is to set bit 1 of configure control
register (index 02h) to 1.
The AAEON initial watchdog timer program is illustrated below.
This program is applied only to DOS and Win 9x.
Example :
;============================ =======
; Enter the MB PnP mode
;============================ =======
mov al, 87h
out 2eh, al
mov al, 1
out 2eh, al