Advantech Industrial Mini-ITX Motherboard with DDR2/Dual GbE/PCI AIMB-221 - Manual (Page 100)

AIMB-221 User Manual 90
The AIMB-221's watchdog timer can be used to monitor system software operation
and take corrective action if the software fails to function within the programmed
period. This section describes the operation of the watchdog timer and how to pro-
gram it.
A.1 Watchdog timer overview
The watchdog timer is built in to the super I/O controller W83627HF. It provides the
following functions for user programming:
! Can be enabled and disabled by the user's program
! Timer can be set from 1 to 255 seconds or 1 to 255 minutes
! Generates an interrupt or resets signal if the software fails to reset the timer
before time-out
A.2 Reset/Interrupt selection
The J2 jumper is used to select reset or interrupt (IRQ) 11 in the event the watchdog
timer is tripped. See Chapter 1 for detailed jumper settings.
A.3 Programming the Watchdog Timer
The I/O port address of the watchdog timer is 2E (hex) and 2F (hex). 2E (hex) is the
address port. 2F (hex) is the data port. You must first write an address value into
address port 2E (hex), and then write/read data to/from the assigned register through
data port 2F (hex).
Note! The interrupt output of the watchdog timer is a low level signal. It will be
held low until the watchdog timer is reset.