SMC Networks 1232 Series user manual Watchdog time-out pin

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Watchdog time-out pin

For external control purposes, the status of the watchdog time-out event is provided to connector J11 pin 9. This signal goes high when the watchdog resets the system. The software can reset this signal by setting and resetting bit 2 of the I/O port 110h. This signal is also initialized by hardware at power-on.

The following example shows how to reset the watchdog time-out pin:

MOV	DX, 110h	; Control Port
IN	AL, DX	; Read actual value
OR	AL, 04h	; Mask reserved bits and set bit 2
OUT	DX, AL	; Write new value
AND	AL, FBh	; Mask reserved bits and reset bit 2
OUT	DX, AL	; Write new value

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