Archive for March, 2008

AVR Microcontroller Prototype Board

Sunday, March 9th, 2008

The folks at Evil Mad Scientist Laboratories whipped up an elegant little kit that includes an ATmega168 AVR Micro-controller, 4 or 5 discrete components, and a circuit board.

The Atmel AVR micro-controllers are awesome. They cross three particular barriers to entry that I arbitrarily chose prior to screwing around with micro-controllers.


  • Price: $10 per useful part The Atmel series ranges from less than $1/part to a bit north of $10/part for the über-deluxe controllers. The ATmega168 in this kit can be had for less than $5/each and includes 23 I/O lines (6 of which can be used for ADC), 16K of program memory, and can run up at speeds up to 20MHZ.
  • USB based Programmer less than $50 LadyAda sells a simple USB programmer (based on the Atmel chips — it implements a USB stack in software!) for $22. It works great, once you fix this particular bug (which involves replacing two resistors with wires; not hard).
  • Easy & Powerful Programmability (on a Mac) Code for the Atmel series of chips is written in C and compiled quite easily via gcc. The ObDev folks have made an easy to install package available. It just works. Better, the chips support in system programming (without sacrificing pins for I/O!) and, thus, “build and run” in Xcode re-loads the code on the target chip without having to either power down the board or remove the chip from the circuit. Edit-compile-run is very very fast.

    The code, itself, is pretty straightforward. The header files provide all the #defines needed to deal with all the random I/O based hardware functionality quite straightforward. The chips, themselves, are exceptionally flexible, with the ability to reconfigure what pins do what in software.

    The hardest part is remembering which pin maps to what random #define’d symbol.

    Mooninites & Lemur

    The Atmel chips are, in fact, the same chips (almost the same exact chip — the proto boards use a slightly less expensive part in that it doesn’t have quite as many I/O ports) used in the Peggy Board (also from EMSL). I picked up the ladyada programmer and grabbed the source from EMSL.

    I had simple animation up and running within a couple of hours, most of that time being consumed by dealing with the now fixed USBTiny programmer bug. Not much longer after that and I had a pretty neat line based animation.

    Jamie over at Noise Land Arcade else has grabbed the code and made a neat animated pacman sign (video here).

Which brings me to this kit: This credit card sized board is designed quite specifically for prototyping ATmega168 (and several others) based projects. Beyond including a bit of room for adding a couple of 8-pin DIPs (or other random components), the silk screen fully documents the various mnemonics associated with each pin.

First project?

I’m going to build modern style flipper replacement for ’80s and early ’90s Williams/Bally pinball machines. The old school flippers require more maintenance and tend to fail gracelessly, taking out other discrete components upon failure.

This board is total overkill. I really only need an 8 pin Atmel controller per flipper; maybe one chip for both flippers, if I optimize.

But at $9/each for the board, controller and discrete components (including shipping and CA tax) in lots of 10, I might just stick with building it out on the EMSL prototype board.

As with many EMSL projects, everything is open source. The board is single sided and easy to etch, but silk screening on the various documentation bits would be difficult.

Daemon (by Leinad Zeraus)

Friday, March 7th, 2008

I just finished reading Leinad Zeraus’s book Daemon.

In short, it computer oriented, current themed, science fiction that is the polar opposite of Digital Fortress.

The book strikes an excellent balance between depth of plot and sheer unadulterated action.

I would like to say “fun read”, but that isn’t correct. The store is often brutal, but such brutality makes sense in context.

And the technical side of the book pretty close to dead on without being overwhelmingly pedantic in detail. Where Brown’s Digital Fortress dove into incredible detail of ludicrously incorrect descriptions of technology, Daemon provides fast paced use of network and social hacking terms that the knowledgeable will find appropriate and the ignorant will be able to gloss over without being lost in the story.

The book also does a brilliant job of tieing together various memes from modern computing; bots, DDOSes, MMORPGs and the pervasiveness of databases throughout the modern world.

Great book. If you liked Neuromancer, Snow Crash or Shockwave Rider, you’ll probably dig Daemon.

I’m looking forward to the sequel in November.


Tuesday, March 4th, 2008
Ice Plant Detail

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How to harvest a turkey.

Monday, March 3rd, 2008
Turkey's Hanging Until Harvest

Mmm…. Turkey. Yum. See that big dude on the right with the snood hanging down?

That would be our thanksgiving dinner this year. I reserved a turkey with a rather awesome local poultry farmer, Paul Hain, earlier in the season. He raised the turkeys in his walnut orchard. Completely organic.

The turkey needed to be picked up at farm on the weekend before thanksgiving and Paul invited us to come down, tour the farm and participate in the turkey harvest, if we wanted.

Ben and I jumped at the chance. To play a role in the harvest of the turkey — to actually know what happens between “bird eating bugs & grain” to “me eating the bird — is something that we both feel is important knowledge.

Personally, I find it hypocritical to both eat a food and be unwilling to acknowledge how said food is produced.

Enough of the PC BS. If you don’t want to read about animal slaughter, see pictures of blood, or know how a turkey goes from walking around to ready to cook, don’t click through to the full story.

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Walking Sticks

Sunday, March 2nd, 2008
Bil Pile of Stick Bugs

For his fifth birthday, Roger was given a pair of stick bugs (with our permission).

Little did any of us know how much stick bugs are the epitome of the gift that keeps on giving.

Many Phasmatodea don’t really need a mate to reproduce, reproducing by parthenogenesis instead.

I’m not sure if that was the case with our original pair. If not, we clearly had a male and a female.

This shot is of the current generation, probably the 4th generation since the original pair came home nearly two years ago.

Yes, that is a pile of hundreds of very tiny, and very much alive, stick bugs.

Anyone want a stick bug? Easy pets to care for.

Individual Stick Bug Study

As their name implies, stick bugs tend to spend a lot of time trying to look like a stick.

Sometimes they are more successful than others. This little guy — the leaf was about 1.25 inches across at the widest point — is trying desperately to look like a bare twig hanging out in the breeze.

Not going so well.

These particular stick bugs eat rose and citrus leaves. We are careful to not allow any to get loose, but they are so small when freshly hatched (from eggs that look exactly like big stick bug poo) that I would imagine some have managed to get loose.

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