AIMB-221 User Manual
92
A.3.1
Example Programs
Enable watchdog timer and set 10 seconds as the timeout interval
;-----------------------------------------------------------
Mov dx,2eh
; Unlock W83627HF
Mov al,87h
Out dx,al
Out dx,al
;-----------------------------------------------------------
Mov al,07h
; Select registers of watchdog timer
Out
dx,al
Inc
dx
Mov
al,08h
Out
dx,al
;-----------------------------------------------------------
Dec dx
; Enable the function of watchdog timer
Mov
al,30h
Out
dx,al
Inc
dx
Mov
al,01h
Out
dx,al
;-----------------------------------------------------------
Table A.1: Watchdog timer registers
Address of
register (2E)
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 function 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 seconds 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 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 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
"timeout".
AA (hex)
-----
Write this address to I/O port 2E (hex) to lock the watch-
dog timer 2.
Summary of Contents for AIMB-221
Page 11: ...Chapter 1 1 Hardware Configuration...
Page 25: ...Chapter 2 2 Connecting Peripherals...
Page 30: ...AIMB 221 User Manual 20 2 4 Front Panel Connectors JFP1 JFP2 JFP3...
Page 38: ...AIMB 221 User Manual 28 2 9 Parallel Port LPT1...
Page 52: ...AIMB 221 User Manual 42 2 21 Serial ATA Interface SATA1 SATA2 SATA3 SATA4...
Page 57: ...47 AIMB 221 User Manual Chapter 2 Connecting Peripherals 2 24 LVDS...
Page 60: ...AIMB 221 User Manual 50...
Page 61: ...Chapter 3 3 Award BIOS Setup...
Page 80: ...AIMB 221 User Manual 70...
Page 81: ...Chapter 4 4 Chipset Software Installation Utility and VGA Setup...
Page 91: ...Chapter 5 5 LAN Configuration...
Page 95: ...Chapter 6 6 AC97 Audio Setup...
Page 98: ...AIMB 221 User Manual 88...
Page 99: ...Appendix A A Programming the Watchdog Timer...
Page 107: ...97 AIMB 221 User Manual Appendix A Programming the Watchdog Timer...