Category: hardware

A software only solution to the vexing Beagle Bone Black PHY issue

Power cycling BBB’s with clicky relays

Sometimes the Ethernet port on a Beagle Bone Black does not work on power up. It takes either a physical reset button press or a power cycle to fix it. This problem affects all BBB’s and until now could only be solved with hardware hacks.

The final official word from TI on this problem:

There is no solution for this on the BB Black

This sucks. If you are thinking of using a Beagle Bone Black for anything important… then don’t. And don’t bother reading the rest of this article.

If you already are stuck with the Beagle Bone Black and wish that it worked right each and every time you turn it on, then read this article.

Here is a workaround that can guarantee that an unmodified Beagle Bone Black will have a working Ethernet port within a few minutes after power up.

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Deconstructing Kitty

“Google called, and josh.com needs more cats.”

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So today we look inside these amazing cats that can somehow keep on wavin’ using less than 15 microwatts (!) of power. If you are into either ultra low-power or extreme design-for-manufacture, the you will want to see what is inside of these guys!

“What I can not create with an Arduino, I do not understand”, so we then proceed to recreate a lucky cat under Arduino digital control.

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Make your BeagleBone Black am355x magically turn itself on with the built-in alarm clock

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The am335x ARM chip in the BeagleBone Black has a Real Time Clock hidden inside that you can use to have the board spontaneously turn itself on anytime in the next 100 years.

Here I present a new utility to manage that built-in clock from the Linux command line, and explain how to use it to keep time, shutdown, software power cycle, and more!

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More Adventures in Auto-routing – The Big Spin Swap

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It doesn’t matter which side of a resistor goes to which connection, and sometimes switching them around can make a board much easier to route. Same goes for equivalent IO pins on a microcontroller and lots of other cases. Here we see what a big difference a little pin swapping can make, and how to give the TopoR auto-router the freedom to swap your pins for you.

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Blinking Blue- Powering a 3.7 volt LED from a 2.4 volt coin cell with a $0.02 charge pump

www.GIFCreator.me_D8DxdM

Everyone loves blue LEDs and everyone loves coin cell batteries, but if you want to power a blue LED from a coin cell you will need some help. Here is a super-cheap and easy way add a to boost your LED voltage with only an additional capacitor & diode, and a little software.

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Capacitive Coupling Casestudy: Programming The Public Radio without removing it from its sealed shipping box

2017-03-18 13_12_32-the public radio

You’ve probably heard about the refreshingly simple Public Radio (TPR). There is no tuning knob needed since your TPR magically knows your favorite station straight out of the box.

Like most magic, this illusion of simplicity involves a lot of work behind the scenes. Each TPR has to be custom programmed by hand, assembled, and then lovingly packed before being shipped to your door. If only there was a way to program an assembled TPR without opening the sealed box…

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