Boser HS-6036, User Manual

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must constantly proceed a Refresh cycle to Watchdog Timer before its
period setting comes ending of every 1, 2, 10, 20, 110 or 220 seconds
which pre-setting by JP8(5-10). If the Refresh cycle does not active
before Watchdog Timer period cycle, the on board Watchdog Timer
architecture will issue a Reset or NMI cycle to the system.
JP8 (5-10) : Watchdog Timer - Out Period
PERIOD JP8(5-6) JP8(7-8) JP8(9-10)
*1 sec ON ON ON
2 sec OFF ON ON
10 sec ON OFF ON
20 sec OFF OFF ON
110 sec ON ON OFF
220 sec OFF ON OFF
The Watchdog Timer is control by two I/O ports.
443H I/O Read The Enable cycle.
443H I/O Read The Refresh cycle.
045H I/O Read The Disable cycle.
The following sample programs showing how to Enable, Disable
and Refresh the Watchdog Timer:
WDT_EN_RF EQU 0443H
WDT_DIS EQU 0045H
WT_Enable PUSH AX ; keep AX DX
PUSH DX
MOV DX,WDT_EN_RF ; enable the watch-dog timer
IN AL,DX
POP DX ; get back AX, DX
POP AX
RET
WT_Rresh PUSH AX ; keep AX, DX
PUSH DX
MOV DX,WDT_ET_RF ; refresh the watch-dog timer
IN AL,DX
POP DX ; get back AX, DX
POP AX
RET
WT_DISABLE PUSH AX
PUSH DX
MOV DX,WDT_DIS ; disable the watch-dog timer
IN AL,DX
POP DX ; get back AX, DX
POP AX
RET