AFL3-W07A-BT Panel PC
Page 101
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-BT-N1/PC/2G-R20
Page 13: ...AFL3 W07A BT Panel PC Page 1 1 Introduction Chapter 1 ...
Page 21: ...AFL3 W07A BT Panel PC Page 9 2 Unpacking Chapter 2 ...
Page 25: ...AFL3 W07A BT Panel PC Page 13 3 Installation Chapter 3 ...
Page 54: ...AFL3 W07A BT Panel PC Page 42 4 BIOS Setup Chapter 4 ...
Page 82: ...AFL3 W07A BT Panel PC Page 70 5 System Maintenance Chapter 5 ...
Page 88: ...AFL3 W07A BT Panel PC Page 76 6 Interface Connectors Chapter 6 ...
Page 99: ...AFL3 W07A BT Panel PC Page 87 Appendix A A Regulatory Compliance ...
Page 104: ...AFL3 W07A BT Panel PC Page 92 B Safety Precautions Appendix B ...
Page 109: ...AFL3 W07A BT Panel PC Page 97 C BIOS Menu Options Appendix C ...
Page 112: ...AFL3 W07A BT Panel PC Page 100 Appendix D D Watchdog Timer ...
Page 115: ...AFL3 W07A BT Panel PC Page 103 E Hazardous Materials Disclosure Appendix E ...