PC6-TANGO • CompactPCI
®
PlusIO • Intel® Atom™ E39xx Processor (APL-I SoC)
Reset
The PC6-TANGO is provided with a supervisor circuit to monitor supply rails like the CPU core voltage,
DDR3L supply voltage 1.35V, 1.05V, 3.3V or 5V.
To force a manual board reset, the PC6-TANGO 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 handle within the front panel contains a micro switch that is used to generate a power button
event. By pressing the handle's red push button a pulse is triggered.
Animated GIF: www.ekf.com/c/ccpu/img/reset_400.gif
NOTE: To prevent the board from causing a power button override, the handle should be closed again
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
S4/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 PC6-TANGO
indicates the different power states.
WARNING: The PC6-TANGO will enter the power state S4/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 function of the micro switch within the handle could be changed from “power button” to
“system reset” by UEFI/BIOS settings. In this case the front panel handle behaves like the tactile switch.
The manual reset push-button and the functionality of the front panel handle could also be disabled
by UEFI/BIOS settings.
An alternative (and recommended) way to generate a system reset is to activate the signal PRST#
located on CompactPCI
®
PlusIO 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 PC6-TANGO 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.
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