POC-17i/19i Series
Page 111
NOTE:
The following discussion applies to DOS environment. IEI support is
contacted or the IEI website visited for specific drivers for more
sophisticated operating systems, e.g., Windows and Linux.
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 C-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, the 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.
Содержание POC-17i
Страница 15: ...POC 17i 19i Series Page 1 Chapter 1 1 Introduction...
Страница 25: ...POC 17i 19i Series Page 11 Chapter 2 2 Unpacking...
Страница 28: ...POC 17i 19i Series Page 14 1 Touch pen 1 User manual CD and driver CD...
Страница 29: ...POC 17i 19i Series Page 15 Chapter 3 3 Installation...
Страница 56: ...POC 17i 19i Series Page 42 Chapter 4 4 System Maintenance...
Страница 63: ...POC 17i 19i Series Page 49 Chapter 5 5 BIOS Setup...
Страница 89: ...POC 17i 19i Series Page 75 Chapter 6 6 Software Drivers...
Страница 113: ...POC 17i 19i Series Page 99 Figure 6 39 Reboot the Computer...
Страница 114: ...POC 17i 19i Series Page 100 Appendix A A Safety Precautions...
Страница 121: ...POC 17i 19i Series Page 107 Appendix B B BIOS Options...
Страница 124: ...POC 17i 19i Series Page 110 Appendix C C Watchdog Timer...
Страница 127: ...POC 17i 19i Series Page 113 Appendix D D Hazardous Materials Disclosure...