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Miscellaneous – ADLINK Express-IBR User Manual

Page 41

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Chapter 3

Hardware

Express-IBR

Reference Manual

35

Miscellaneous

Watchdog Timer

The Watchdog Timer (WDT) restarts the system if a mishap occurs, ensuring proper start-up after the

interruption. Possible problems include failure to boot properly, the application software’s loss of control,

failure of an interface device, unexpected conditions on the bus, or other hardware or software malfunctions.
Use the ADLINK Intelligent Device Interface (AIDI) Library to configure the WDT interface. AIDI driver

information is available on the Express-IBR Product page at:

http://www.adlinktech.com

. An AIDI demo

program and the AIDI User’s Manual showing how to use the WDT function also reside in the Utilities tab
of the Express-IBR Product page.

The WDT (Watchdog Timer) can be used both during the boot process and during normal system operation.

During the Boot process – If the OS fails to boot in the time interval set in the BIOS, the system will
reset.
Enable the WDT in the Custom Configuration Screen of BIOS Setup. Set the WDT for a time-out

interval in seconds, between 1 and 255, in one second increments. Ensure you allow enough time for the
boot process to complete and for the OS to boot. The OS or application must tickle the WDT as soon as

it comes up. This can be done by accessing the hardware directly or through a BIOS call.

During System Operation – The user can set up the WDT hardware through a BIOS call or by accessing
the hardware directly using the AIDI Library. The BIOS call must tickle the WDT in the time set when
the WDT is initialized or the system will be reset.

Watchdog Code example – ADLINK provides a source code example (AIDI demo program) on the
Express-IBR Product page of the web site illustrating how to control the WDT. The code example can
be easily copied to your development environment to compile and test or make any desired changes

before compiling.

TPM (Trusted Platform Module)

The Express-IBR provides a hardware chip called a Trusted Platform Module which is dedicated for security

functions. Trusted Computing is an industry standard created for personal computer security. The BIOS
allows you to enable or disable the TPM.

Hardware Voltage and Temperature Monitor

The Express-IBR provides a hardware monitor to ensure the health of your embedded system with built-in
support for monitoring and control of system temperatures, fan speeds, and critical module voltage levels.

The AIDI Library provides simple APIs at the application level to support these functions and adds alarm

functions when voltage or temperature levels exceed the upper or lower limits set by the user. AIDI driver
information for the Express-IBR is available on the Express-IBR Product page at:

http://www.adlinktech.com

. An AIDI demo program and the AIDI User’s Manual showing how to use the

Hardware Monitor also reside in the Utilities tab of the Express-IBR Product page.

C104

VCC_12V

D104

VCC_12V

C105

VCC_12V

D105

VCC_12V

C106

VCC_12V

D106

VCC_12V

C107

VCC_12V

D107

VCC_12V

C108

VCC_12V

D108

VCC_12V

C109

VCC_12V

D109

VCC_12V

C110

GND

D110

GND

Table 3-6. COM Express C-D Connector Signal Descriptions (CN7) (Continued)