Specifications

122 PCA-6180 User's Manual
Watchdog Timer Registers
Address of
register (2E)
Attribute
Read/Write
Value (2F) and description
87 (hex) -----
Write this address to I/O address port
2E (hex) twice to unlock theW83627HF
07 (hex) write
Write 08 (hex) to select register of
watchdog timer.
30 (hex) write
Write 01 (hex) to enable the function of
the watchdog timer. Disabled is set as
default.
F5 (hex) write
S et seconds or minutes as units fo r the
tim er.
W rite 0 to bit 3: set second as counting
unit. [default]
Write 1 to bit 3: set minute 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 interrupt 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 7: Write 1 to enable mouse to reset
the timer, 0 to disable [default]
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 automatically
return to 0. [default=0]
Bit 4: Read status of watchdog timer, 1
means timer is "time out".
AA (hex) -----
Write this address to I/O port 2E (hex)
to lock the watchdog tim er.
Table A-1: Watchdog timer registers