AFL3-W07A-AL Panel PC
Page 97
NOTE:
The following discussion applies to DOS. Contact IEI support or visit the IEI
website for drivers for other operating systems.
The Watchdog Timer is a hardware-based timer that attempts to restart the system when it
stops working. The system may stop working because of external EMI or software bugs.
The Watchdog Timer ensures that standalone systems like ATMs will automatically
attempt to restart in the case of system problems.
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 AFL3-W07A-AL
Page 13: ...AFL3 W07A AL Panel PC Page 1 1 Introduction Chapter 1...
Page 21: ...AFL3 W07A AL Panel PC Page 9 2 Unpacking Chapter 2...
Page 25: ...AFL3 W07A AL Panel PC Page 13 3 Installation Chapter 3...
Page 50: ...AFL3 W07A AL Panel PC Page 38...
Page 51: ...AFL3 W07A AL Panel PC Page 39 4 BIOS Setup Chapter 4...
Page 79: ...AFL3 W07A AL Panel PC Page 67 5 System Maintenance Chapter 5...
Page 84: ...AFL3 W07A AL Panel PC Page 72 6 Interface Connectors Chapter 6...
Page 95: ...AFL3 W07A AL Panel PC Page 83 Appendix A A Regulatory Compliance...
Page 100: ...AFL3 W07A AL Panel PC Page 88 B Safety Precautions Appendix B...
Page 105: ...AFL3 W07A AL Panel PC Page 93 C BIOS Menu Options Appendix C...
Page 107: ...AFL3 W07A AL Panel PC Page 95 Save as User Defaults 66 Restore User Defaults 66...
Page 108: ...AFL3 W07A AL Panel PC Page 96 Appendix D D Watchdog Timer...
Page 111: ...AFL3 W07A AL Panel PC Page 99 E Hazardous Materials Disclosure Appendix E...
