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Russell Graves
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Last week, I grumbled about the state of SRAM use in common Arduino libraries. This week, I'm introducing my first solution - a serial logging library that uses zero SRAM except when actually printing.

Instead of a buffer and interrupt based system (the stock Serial library), I use a much slimmer method that just bangs bits out onto the UART as needed.

You save 177 bytes of SRAM (out of 2048 bytes on an Uno) by using this as a drop-in replacement for the Serial library if you're just logging output. Enjoy!

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And now, for the first in a series of posts about Arduino programming, memory use, and "not being an idiot with embedded programming."

I go through the global SRAM use ("Dynamic Memory") use of a bunch of reasonably common Arduino libraries and explain where they're using memory - including a reasonably terrible library written by someone at SparkFun that uses over 600 bytes of SRAM to handle ESP8266 AT client connections.

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If last week's overview of my button box didn't have enough detail, this week's post will be of great interest to you! This is the technical details of my build, an awful lot of lessons learned, and a parts list!

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Back to small electronics. I built a "Button Box" for my daughter out of some parts and an Arduino. It has buttons, LEDs, multi-color LEDs, and an LCD screen - but, definitely a lot of buttons.

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Like him or not, Trump is our new President. And, like it or not, America is acting an awful lot like an empire on the backside of our arc through history. This week is about progress, decline, the "Religion of Progress," and includes some useful thoughts on where things might go, and what might be useful for you to consider going forward.

And if you don't care about any of that, I'll be back to talking about small electronics next week.

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My first research post of 2017: How feasible is 350kW charging for the current Tesla 100kWh battery packs?

My conclusion: Entirely plausible! The internal resistance is low and drops at high temperatures, Tesla supports heating the pack for lower internal resistance, and if you treat the whole pack as a thermal mass, the temperature rise from this type of high speed charging isn't enough to be a problem.

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New Years Resolutions: More research posts, engineer less distraction in my life.

When was the last time you went even a day without constant interrupt distractions? Wasn't it nice? You can do that - for your life! I've shared some of the changes I've been making, and it's pretty straightforward stuff.

Join me!

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Last week, I tore down a BionX 350 HT RR L - this week, I rebuild it!

Merry Christmas!

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Another week, another battery pack teardown. This week, I pull apart a rear rack 37V 9.6Ah BionX pack - it's the same capacity as the normal packs, but a very different cell layout.

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As promised last week, this week is a teardown of a 48V BionX battery pack!

This is a beautifully modular pack inside - that you can't get replacement parts for, because BionX won't sell them. It's a substantial advance over the older packs, and has some neat features I've not seen in other packs yet.
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