AFL3-W15C/W19C/W22C-ADLP
Page 134
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-W15C-ADLP
Page 17: ...AFL3 W15C W19C W22C ADLP Page 1 1 Introduction Chapter 1...
Page 31: ...AFL3 W15C W19C W22C ADLP Page 15 2 Unpacking Chapter 2...
Page 36: ...AFL3 W15C W19C W22C ADLP Page 20 3 Installation Chapter 3...
Page 65: ...AFL3 W15C W19C W22C ADLP Page 49 4 BIOS Setup Chapter 4...
Page 110: ...AFL3 W15C W19C W22C ADLP Page 94 5 System Maintenance Chapter 5...
Page 115: ...AFL3 W15C W19C W22C ADLP Page 99 6 Interface Connectors Chapter 6...
Page 134: ...AFL3 W15C W19C W22C ADLP Page 118 Appendix A A Regulatory Compliance...
Page 140: ...AFL3 W15C W19C W22C ADLP Page 124 B Safety Precautions Appendix B...
Page 146: ...AFL3 W15C W19C W22C ADLP Page 130 C BIOS Menu Options Appendix C...
Page 149: ...AFL3 W15C W19C W22C ADLP Page 133 Appendix D D Watchdog Timer...
Page 152: ...AFL3 W15C W19C W22C ADLP Page 136 Appendix E E Error Beep Code...
Page 154: ...AFL3 W15C W19C W22C ADLP Page 138 Appendix F F Hazardous Materials Disclosure...
