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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Idea Dump 2018

As each year passes and my to-do lists get longer, I have to accept that I will die long before I will get to make and do everything I want to.

Here are some things that I probably will never get to, but maybe you will? Don’t let the crackpot-stream-of-consciousness-style throw you, I believe most of these ideas could actually be successful and profitable… with some work.

Let me know if you are truly interested and I will try to share any effort I’ve already invested to give you a head start….

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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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How a Bitcoin is not a Dollar

There is no intrinsic value to a BitCoin because it is an anonymous IOU written by no one.

I want you to give me half of your doughnut.

I can offer to give you a signed IOU that says “Josh will give the holder of this IOU 1/2 doughnut”. The more you trust that I will actually honor the IOU, the more it is worth to you. You might even be able to trade that IOU to someone else for something that they have and you want… assuming they also think there is some chance that I will honor it.

Instead of writing the IOU, now imagine that I write a program that generates random sequences of letters on my computer. I let that program run for a very, very long time until it happens to generate something like “IOU 1/2 doughnut”. I print this out and I offer to trade it to you for 1/2 your doughnut.

YOU: So if I take this note, someday I can give it back to you and you'll give me something yummy?
ME : Nope. This is not an IOU from me. It was randomly generated by a computer.
YOU: So who owes me the 1/2 a doughnut?
ME : No one! But it took the computer a really long time to generate this note at random!
YOU: If there is no one who will pay me back, then why would I ever accept this note?
ME : You can try to trade it to someone else for something they have and you want!

A dollar is an IOU from the government, a BitCoin is an IOU from no one…

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