Nexcom Peak 550, User Manual

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Peak 550/PISA 550 User’s Guide
Watch Dog Timer A-4
An Example
a. Enable watchdog timer
b. Select I/O port F2 & set WDT timer at 1 sec interval
c. Select NMI
d. Enable WDT
e. Clear WDT
f. Disable WDT
a. Set RTC to generate WDT timer source “SQW” to generate 0.5 sec. duty cycle
timer source
MOV AL, 0A ; Set RTC output signal “SQW” to generate 0.5 sec.
cycling timer
MOV DX, 070
OUT DX, AL
MOV AL, 2F
MOV DX, 071
OUT DX, AL
MOV AL, 0B ; Enable “SQW” signal pin active
MOV DX, 070
OUT DX, AL
MOV AL, 0A
MOV DX, 071
OUT DX, AL