EKF SC3-LARGO - PG (Power Good) LED; GP (General Purpose) LED

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User Guide • SC3-LARGO • CompactPCI

Serial CPU Board • Intel

Core

5xxx Processor

PG (Power Good) LED

The SC3-LARGO offers a bicolour LED labelled PG located within the front panel. After system reset,

this LED defaults to signal different power states:

< Off Sleep state S3, S4 or S5

< Green Healthy

< Yellow blink Front panel handle open

< Red steady Hardware failure

< Red blink Software failure

To enter the PG LED state Software Failure, the bit PGLED in the board control register CTRLL_REG

must be set. The PG LED remains in this red blinking state until this bit is cleared. After that it falls

back to its default function.

GP (General Purpose) LED

This programmable bicolour LED can be observed from the SC3-LARGO front panel. The status of the

red part within the LED is controlled by the GPIO18 of the PCH QM87. Setting GPIO18 to “1" will

switch on the red LED. Turning on or off the green LED is done by setting the bit GPLED in the board

control register CTRLH_REG.

The GP LED is not dedicated to any particular hardware or firmware function with exception of special

power states of the LED PG as described above. Nevertheless, a red blinking GP LED is an indication

that the BIOS code couldn't start.

While the CPU card is controlled by the BIOS firmware, the GP LED is used to signal board status

information during POST (Power On Self Test). After successful operating system boot, the GP LED

may be freely used by customer software. For details please refer to

www.ekf.com/s/sc3/firmware/biosinfo.txt.