Advantech AIMB-556, User Manual

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AIMB-556 User Manual 98
Table A.1: Watchdog timer registers
Address 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
W83627HG
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 sec-
ond as counting unit. [default]. Write
1 to bit 3: set minutes as counting
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.