Reset. EKF PC3-ALLEGRO

User Guide • PC3-ALLEGRO • CompactPCI

®

PlusIO CPU Board • Intel® i7-3xxx Processor

Reset

The PC3-ALLEGRO is provided with several supervisor circuits to monitor supply rails like the CPU core voltage, 1.5V, 3.3V or 5V. This circuitry is responsible also to generate a clean power-on reset signal.

To force a manual board reset, the PC3-ALLEGRO offers a small tactile switch within the front panel.

This push-button is indent mounted and requires a tool, e.g. a pen to be pressed, preventing from being inadvertently activated.

The ejector within the front panel contains a micro switch that is used to generate a power button event. This is done by pushing the red button of the ejector until the handle unlocks without ejecting the board. Immediately after that push up the ejector back to its original position (the red button jumps up as well). Animated GIF: www.ekf.com/c/ccpu/img/reset_400.gif

NOTE: To prevent the board to cause a power button override, the handle should be closed immediately after unlocking the front panel handle. A power button override is triggered by opening the front panel handle for at least 4 seconds, which results in bringing the board to power state S5.

In case of entering this state, unlock and lock the front panel handle a 2 nd

time to reenter normal power state S0 again. See also section 'PG (Power Good) LED' to see how the PC3-ALLEGRO indicates the different power states.

WARNING: The PC3-ALLEGRO will enter the power state S5 if the front panel handle is not closed properly when the system powers up. An open handle is signalled by a yellow blinking ‘PG LED’.

The manual reset push-button and the power button functionality of the front panel handle could be passivated by BIOS settings.

An alternative (and recommended) way to generate a system reset is to activate the signal PRST# located on

CompactPCI

connector J2 pin C17. Pulling this signal to GND will have the same effect as to push the tactile reset switch.

The healthy state of the PC3-ALLEGRO is indicated by the LED PG (Power Good) located in the front panel. This bicoloured LED signals different states of the board (see section below). As soon as this

LED begins to lite green, all power voltages are within their specifications and the reset signal has been deasserted.

© EKF -28- ekf.com

User Guide • PC3-ALLEGRO • CompactPCI

®

PlusIO CPU Board • Intel® i7-3xxx Processor

5

6

7

8

<4s

3

4

1

2

© EKF -29- ekf.com