EKF SC1-ALLEGRO, User Manual

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User Guide • SC1-ALLEGRO •
CompactPCI ® Serial
CPU Board • Intel® i7-3xxx Processor
EB (Ethernet Backplane) LED
To monitor the link status and activity on both Ethernet ports attached to the backplane via the
CompactPCI ®
Serial connector P6 a single bicoloured LED is provided in the front panel. The states are
decoded as follows:
1_ETH 2_ETH LED EB
no link no link OFF
link no link GREEN
no link link YELLOW
link link GREEN/YELLOW
Blinking of the LED EB in the appropriate colour means that there is activity on the port.
Main Power Supply Control (PS_ON#)
The SC1-ALLEGRO draws its power from the +12V main supply rail defined by the
CompactPCI ®
Serial
specification. The board has been designed to control this main power supply by use of the signal
PS_ON# (connector P1 pin E2). If the system enters the sleep state S5 (soft off), the signal PS_ON#
is pulled high, hence the main power supply is switched-off. The SC1-ALLEGRO is held in soft off state
until a power management event (e.g. power button event triggered by the front panel handle) brings
back the system to the S0 state.
In order to work as described above and to generate clean signals on PS_ON#, the stand-by voltage
+5VSTB is necessary. This optional power rail, tied to connector P1 pin B1, is also part of the
CompactPCI ®
Serial specification. The stand-by power rail must be switched-on “always”, independent
of the state of PS_ON#.
Nevertheless, +5VSTB is not mandatory to operate the SC1-ALLEGRO. If no stand-by power is
available, the board creates this voltage from the main power rail. In this case it is important that the
PS_ON# signal is pulled down somewhere in the system.
Power Supply Status (PWR_FAIL#)
Power supply failures may be detected before the system crashes down by monitoring the signal
PWR_FAIL#. This active low line (connector P1 pin F3) is an addition to the
CompactPCI ®
Serial
specification and may be driven by the power supply. PWR_FAIL# signals the possible failure of the
main supply v12V. On the SC1-ALLEGRO the signal PWR_FAIL# is routed to GPIO6 of the
QM77 PCH to analyse the state of the power supply unit.
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