AFL-xxx-9103 Panel PC
Page 162
NOTE:
The following discussion applies to DOS environment. IEI support is
contacted or the IEI website visited for specific drivers for more
sophisticated operating systems, e.g., Windows and Linux.
The Watchdog Timer is provided to ensure that standalone systems can always recover
from catastrophic conditions that cause the CPU to crash. This condition may have
occurred by external EMIs or a software bug. When the CPU stops working correctly,
Watchdog Timer either performs a hardware reset (cold boot) or a Non-Maskable Interrupt
(NMI) to bring the system back to a known state.
A BIOS function call (INT 15H) is used to control the Watchdog Timer.
INT 15H:
AH – 6FH Sub-function:
AL – 2:
Sets the Watchdog Timer’s period.
BL:
Time-out value (Its unit-second is dependent on the item “Watchdog
Timer unit select” in CMOS setup).
Table D-1: AH-6FH Sub-function
Call sub-function 2 to set the time-out period of Watchdog Timer first. If the time-out value
is not zero, the Watchdog Timer starts counting down. When the timer value reaches zero,
the system resets. To ensure that this reset condition does not occur, calling sub-function
2 must periodically refresh the Watchdog Timer. However, the watchdog timer is disabled
if the time-out value is set to zero.
A tolerance of at least 10% must be maintained to avoid unknown routines within the
operating system (DOS), such as disk I/O that can be very time-consuming.
Summary of Contents for AFL-xxx-9103
Page 19: ...AFL xxx 9103 Panel PC Page 1 Chapter 1 1 Introduction...
Page 35: ...AFL xxx 9103 Panel PC Page 17 Chapter 2 2 Motherboard...
Page 59: ...AFL xxx 9103 Panel PC Page 41 Chapter 3 3 Installation...
Page 82: ...AFL xxx 9103 Panel PC Page 64 Chapter 4 4 System Maintenance...
Page 94: ...AFL xxx 9103 Panel PC Page 76 Chapter 5 5 BIOS Setup...
Page 99: ...AFL xxx 9103 Panel PC Page 81 BIOS Menu 2 Advanced...
Page 136: ...AFL xxx 9103 Panel PC Page 118 Chapter 6 6 Driver Installation...
Page 169: ...AFL xxx 9103 Panel PC Page 151 Appendix A A BIOS Options...
Page 172: ...AFL xxx 9103 Panel PC Page 154 Appendix B B Terminology...
Page 176: ...AFL xxx 9103 Panel PC Page 158 Appendix C C Digital I O Interface...
Page 179: ...AFL xxx 9103 Panel PC Page 161 Appendix D D Watchdog Timer...
Page 182: ...AFL xxx 9103 Panel PC Page 164 Appendix E E Address Mapping...
Page 184: ...AFL xxx 9103 Panel PC Page 166 E 2 Input Output IO Figure E 2 Input Output IO 1 of 2...
Page 185: ...AFL xxx 9103 Panel PC Page 167 Figure E 3 Input Output IO 2 of 2...
Page 186: ...AFL xxx 9103 Panel PC Page 168 E 3 Interrupt Request IRQ Figure E 4 Interrupt Request IRQ...
Page 187: ...AFL xxx 9103 Panel PC Page 169 E 4 Memory Figure E 5 Memory...
Page 188: ...AFL xxx 9103 Panel PC Page 170 Appendix F F Compatibility...
Page 191: ...AFL xxx 9103 Panel PC Page 173 Appendix G G Hazardous Materials Disclosure...
Page 195: ...AFL xxx 9103 Panel PC Page 177 Appendix H H AC 97 Audio Codec...