
AIMB-760 User Manual 84
Table A.1: Watchdog timer registersAddress of 
register (2E)
Attribute
Read/Write Value (2F)
       & 
description
87 (hex) ----- Write this address to I/O address 
port 2E (hex) twice to unlock the 
W83627HF
07 (hex) write Write 08 (hex) to select register of 
watchdog timer.
30 (hex) write Write 01 (hex) to enable the func-
tion of the watchdog timer. Disabled 
is set as default.
F5 (hex) write Set seconds or minutes as units for 
the timer.
Write 0 to bit 3: set 
second as count-
ing unit. [default]
Write 1 to bit 3: set 
minutes as count-
ing unit
F6 (hex) write 0: stop timer [default]
01~FF (hex): The amount of the 
count, in seconds or minutes, 
depends on the value set in register 
F5 (hex). This number decides how 
long the watchdog timer waits for 
strobe before generating an inter-
rupt or reset signal. Writing a new 
value to this register can reset the 
timer to count with the new value.
F7 (hex) read/write Bit 6: Write 1 to enable keyboard to 
reset the timer, 0 to disable.[default]
Bit 5: Write 1 to generate a timeout 
signal immediately and automati-
cally return to 0. [default=0]
Bit 4: Read status of watchdog 
timer, 1 means timer is “timeout”.
AA (hex) ----- Write this address to I/O port 2E 
(hex) to lock the watchdog timer 2.