S19A/S24A-QM87i-i5 Marine Panel PC
Page 120
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 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. While 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 S19A-QM87i-i
Page 13: ...S19A S24A QM87i i5 Marine Panel PC Page 1 Chapter 1 1 Introduction ...
Page 24: ...S19A S24A QM87i i5 Marine Panel PC Page 12 Chapter 2 2 Unpacking ...
Page 28: ...S19A S24A QM87i i5 Marine Panel PC Page 16 Chapter 3 3 Installation ...
Page 53: ...S19A S24A QM87i i5 Marine Panel PC Page 41 Chapter 4 4 On Screen Display OSD Controls ...
Page 59: ...S19A S24A QM87i i5 Marine Panel PC Page 47 Chapter 5 5 BIOS Setup ...
Page 97: ...S19A S24A QM87i i5 Marine Panel PC Page 85 Chapter 6 6 Maintenance ...
Page 102: ...S19A S24A QM87i i5 Marine Panel PC Page 90 Chapter 7 7 Interface Connectors ...
Page 104: ...S19A S24A QM87i i5 Marine Panel PC Page 92 Figure 7 2 Main Board Layout Diagram Solder Side ...
Page 118: ...S19A S24A QM87i i5 Marine Panel PC Page 106 Appendix A A Regulatory Compliance ...
Page 123: ...S19A S24A QM87i i5 Marine Panel PC Page 111 Appendix B B Safety Precautions ...
Page 128: ...S19A S24A QM87i i5 Marine Panel PC Page 116 Appendix C C BIOS Menu Options ...
Page 131: ...S19A S24A QM87i i5 Marine Panel PC Page 119 Appendix D D Watchdog Timer ...
Page 134: ...S19A S24A QM87i i5 Marine Panel PC Page 122 E Hazardous Materials Disclosure Appendix E ...