AFL-08AH-N270-CR Panel PC
Page 98
NOTE:
The following discussion applies to DOS environment.
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 EMI 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. While 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-08AH-N270-CR
Page 14: ......
Page 15: ...AFL 08AH N270 CR Panel PC Page 1 1 Introduction Chapter 1...
Page 23: ...AFL 08AH N270 CR Panel PC Page 9 2 Detailed Specifications Chapter 2...
Page 31: ...AFL 08AH N270 CR Panel PC Page 17 Figure 2 9 PIFA Antenna and Wireless Module...
Page 32: ...AFL 08AH N270 CR Panel PC Page 18 3 Unpacking Chapter 3...
Page 35: ...AFL 08AH N270 CR Panel PC Page 21 4 Installation Chapter 4...
Page 52: ...AFL 08AH N270 CR Panel PC Page 38 5 System Maintenance Chapter 5...
Page 59: ...AFL 08AH N270 CR Panel PC Page 45 Aluminum cover Plastic cover...
Page 60: ...AFL 08AH N270 CR Panel PC Page 46 6 AMI BIOS Setup Chapter 6...
Page 97: ...AFL 08AH N270 CR Panel PC Page 83 A System Specifications Appendix A...
Page 101: ...AFL 08AH N270 CR Panel PC Page 87 B Safety Precautions Appendix B...
Page 107: ...AFL 08AH N270 CR Panel PC Page 93 C BIOS Configuration Options Appendix C...
Page 111: ...AFL 08AH N270 CR Panel PC Page 97 D Watchdog Timer Appendix D...
Page 114: ...AFL 08AH N270 CR Panel PC Page 100 E International Standards Compliance Appendix E...