PPC2-Cxxx-EHL Series Panel PC
Page 82
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 sy stems 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 No n-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 reac hes 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 PPC2-C-EHL Series
Page 13: ...PPC2 Cxxx EHL Series Panel PC Page xiii Table 5 23 USB 3 2 Gen 1 Connector USB3_CON1 69...
Page 14: ......
Page 15: ...PPC2 Cxxx EHL Series Panel PC Page 1 1 Introduction Chapter 1...
Page 36: ...PPC2 Cxxx EHL Series Panel PC Page 22 2 Unpacking Chapter 2...
Page 39: ...PPC2 Cxxx EHL Series Panel PC Page 25 3 Installation Chapter 3...
Page 51: ...PPC2 Cxxx EHL Series Panel PC Page 37 Figure 3 12 Secure the Chassis...
Page 68: ...PPC2 Cxxx EHL Series Panel PC Page 54 Chapter 4 4 System Maintenance...
Page 70: ...PPC2 Cxxx EHL Series Panel PC Page 56 5 Interface Connectors Chapter 5...
Page 84: ...PPC2 Cxxx EHL Series Panel PC Page 70 Appendix A A Regulatory Compliance...
Page 89: ...PPC2 Cxxx EHL Series Panel PC Page 75 B Safety Precautions Appendix B...
Page 95: ...PPC2 Cxxx EHL Series Panel PC Page 81 C Watchdog Timer Appendix C...
Page 98: ...PPC2 Cxxx EHL Series Panel PC Page 84 Appendix D D Hazardous Materials Disclosure...