User Manual

element14 is a trademark of Premier Farnell plc 33

plugged into the board or you have a power hungry device or hub plugged into the host

port, then more current may needed from the DC supply.

Power routed to the board via the expansion header could be provided from power

derived on a cape. The DC supply should be well regulated and 5V +/-.25V.

5.9 Reset Button

When pressed and released, causes a reset of the board. The reset button used on the

element14 BeagleBone Black is a little larger than the one used on the original

BeagleBone. It has also been moved out to the edge of the board so that it is more

accessible.

5.10 Power Button

A power button is provided near the reset button close to the Ethernet connector. This

button takes advantage of the input to the PMIC for power down features. While a lot of

capes have a button, it was decided to add this feature to the board to ensure

everyone had access to some new features. These features include:

•

Interrupt is sent to the processor to facilitate an orderly shutdown to save files

and to un-mount drives.

•

Provides ability to let the processor put board into a sleep mode to save power.

•

Can alert processor to wake up from sleep mode and restore state before sleep

was entered.

•

Allows board to enter the sleep mode, preserving the RTC clock

If you hold the button down longer than 8 seconds, the board will power off if you release

the button when the power LED turns off. If you continue to hold it, the board will power

back up completing a power cycle.

5.11 Indicators

There are a total of five blue LEDs on the board.

•

One blue power LED indicates that power is applied and the power

management IC is up. If this LED flashes when applying power, it means that an

excess current flow was detected and the PMIC has shut down.

•

Four blue LEDs that can be controlled via the SW by setting GPIO pins.

In addition, there are two LEDs on the RJ45 to provide Ethernet status indication. One is

yellow (100M Link up if on) and the other is green (Indicating traffic when flashing).