WatchDog Timer keep alive trigger

• The controller is intended to be polled regularly
• Activating the watchdog keep-alive is added to controller software polling response
• PC0 momentarily set to output logic low
• If the controller has not recently responded to a poll, the watchdog timer forces reset
• Therefore the watchdog timer interval should be set to little longer than the intended polling interval
• For example: if intended polling is <10seconds between polls, watchdog timeout should be >10seconds