Appendix
EC5-1812CLDNA(B)
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Appendix
Watchdog Programming Guide
EC5-1812CLDNA provides a programmable watchdog timer (WDT) up to 255 levels
and time by minute or second. Watchdog timer overtime event can be programmed to
reset system or generate shielding interrupts.
The following describes WDT program in C language. Note: before operating WDT,
users shall firstly enter WDT programming mode; after finishing WDT configuration,
exit WDT.
The steps to program WDT:
Enter WDT programming mode
Setup WDT operating methods/ enable WDT/disable WDT
Exit WDT programming mode
The following files shall be included:
#include <stdio.h>
#include <dos.h>
#include <bios.h>
#include <stdlib.h>
#include <string.h>
(1)
Enter WDT programming Mode and obtain pm BASE. The watchdog setup
is within p offset register.
outportb(0x2e,0x55); //enter WDT programming mode, write 0x55 in INDEX PORT
//INDEX PORT [4e /2e], DATA PORT [4F/2F]
// read-in register in INDEX, write-in data to register
from DATA.
outportb(0x2e,0x07); //reg0X07, used to select logic device
outportb(0x2f,0x0A); //select logic deviceA,
