Watchdog; Front Panel Leds - EKF SC2-PRESTO CompactPCI User Manual

User Guide • SC2-PRESTO • CompactPCI

Watchdog

An important reliability feature is a software programmable watchdog function. The SC2-PRESTO
contains two of these watchdogs. One is part of the QM87 PCH and also known as TCO Watchdog.
A detailed description is given in the QM87 data sheet. Operating systems like Linux offer a driver
interface to the TCO watchdog.
The behaviour of the 2
activates/deactivates the watchdog and controls its time-out period. The time-out delay is adjustable
in the steps 2, 10, 50 and 255 seconds. After alerting the WD and programming the time-out value,
the related software (e.g. application program) must trigger the watchdog periodically. For details on
programming the watchdog see section "Board Control and Status Register (BCSR)".
This watchdog is in a passive state after a system reset. There is no need to trigger it at boot time. The
watchdog is activated on the first trigger request. If the duration between two trigger requests
exceeds the programmed period, the watchdog times out and a full system reset will be generated.
The watchdog remains in the active state until the next system reset. There is no way to disable it once
it has been put on alert, whereas it is possible to reprogram its time-out value at any time.

Front Panel LEDs

The SC2-PRESTO is equipped with four LEDs which can be observed from the front panel. Three of
these LEDs are labelled according to their primary meaning, but should be interpreted altogether for
system diagnosis:
PG
Green/Red
OFF
OFF
OFF
GREEN
GREEN
YELLOW BLINK
RED
RED BLINK
© EKF
nd
watchdog is defined within a PLD of the SC2-PRESTO, which
LED
GP HD
Green/Red Green/Yellow
GREEN GREEN
GREEN OFF
OFF GREEN
RED BLINK X
X X
X X
X X
X X
®
Serial CPU Board • Intel® Core
Sleep State S5 (Soft Off)
Sleep State S4 (Suspend to Disk/Hibernate)
Sleep State S3 (Suspend to RAM/Standby)
Board Healthy and in S0 State
Front panel handle is unlocked
Hardware Failure - Power Fault
-28-
TM
4xxx Processor
Status
After Reset
Software Failure
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