POC-W24C-ULT3 FHD Medical Panel PC
Page 141
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 POC-W24C-ULT3
Page 16: ...POC W24C ULT3 FHD Medical Panel PC Page 1 1 Introduction Chapter 1 ...
Page 28: ...POC W24C ULT3 FHD Medical Panel PC Page 13 2 Unpacking Chapter 2 ...
Page 34: ...POC W24C ULT3 FHD Medical Panel PC Page 19 3 Installation Chapter 3 ...
Page 60: ...POC W24C ULT3 FHD Medical Panel PC Page 45 4 BIOS Setup Chapter 4 ...
Page 94: ...POC W24C ULT3 FHD Medical Panel PC Page 79 Chapter 5 5 Driver Installation ...
Page 118: ...POC W24C ULT3 FHD Medical Panel PC Page 103 6 System Maintenance Chapter 6 ...
Page 125: ...POC W24C ULT3 FHD Medical Panel PC Page 110 7 Interface Connectors Chapter 7 ...
Page 141: ...POC W24C ULT3 FHD Medical Panel PC Page 126 Appendix A A Regulatory Compliance ...
Page 146: ...POC W24C ULT3 FHD Medical Panel PC Page 131 B Safety Precautions Appendix B ...
Page 152: ...POC W24C ULT3 FHD Medical Panel PC Page 137 C BIOS Menu Options Appendix C ...
Page 155: ...POC W24C ULT3 FHD Medical Panel PC Page 140 Appendix D D Watchdog Timer ...
Page 158: ...POC W24C ULT3 FHD Medical Panel PC Page 143 Appendix E E Hazardous Materials Disclosure ...