Should you not know about these gravatars: The name comes from “Globally Recognized Avatar” which is like your profile picture on facebook or that byline image of the author next to their newspaper article. It’s an image associated with your online persona. The cool thing about doing it online is you can change it at any time and anywhere that image is used (when you leave your plethora of grateful comments on this very blog perhaps?) it will instantly update! How truly meaningless and fun!

For those of you who do not have a gravatar yet: go get one! It’s crazy simple and your icon starts showing up whenever you comment on somebody’s blog etc! Oh the meaningless joy!

For those more paranoid (and this should be ALL of you): the system works by hashing your email address (that’s generally required to comment) and turning it into meaningless (to people) gibbarish. This gibbarish is hauled off to the gravatar server where it’s linked to an image and that’s what gets displayed. Your email address is safe for another day! Hoorays!

Ok, time to go home. A certain game drops at midnight and I need to sleep some time :)

Leave comments and check out your new gravatars!

Warning: this post deals primarily with subjects that by all rights can be called ‘Nerdy as hell.’ Should such material be known to you as dull, boring, somnolent etc. stop now; It’s not worth it.

Onwards!

So recently I’ve been toying around with the idea of physical computing and trying to figure out something to do as a sort of introduction to the whole field before I begin my fully-functional-hexapod-computer-case-mod project (more details see here) There are quite literally hundreds of ways to start out but quite a few of them involve large-ish sums of money up front which doesn’t sound like my kind of dabbling… then: Lo! The Arduino came unto me and bestowed tidings of great joy which shall be to all people!

The Arduino is an open-source physical computing platform based on a simple microcontroller board, and a development environment for writing software for the board. Best of all you can have one and start playing with it for as little as $11.50 (although I opted for the pre-built version with a bit more functionality for $33.00 from my new friends at Sparkfun.) For a dabbler like me it’s perfect :)

Arduino Diecimila in hand I needed a project. Although I had originally aspired to replace the brain in my lovely roomba with the arduino it turns out my roomba was made 6 days BEFORE the i-robot folks implemented their current control scheme. Well boooo (all is not lost though, I have a hardware upgrade for it in the mail which will unlock all of the ROI goodness)

Having previously been a software guy my first idea was to make it say “hello world!”

For those of you who are not “software guys” the FIRST thing that every programmer does in ANY language when they start is make it print out “hello world!” If you want to have good crops and win your wars you offer up a slaughtered goat or virgin. If you want to learn a programming language you make it say “hello world!” This is the way things have been, are, and will always be, as they have been handed down from the ancients and we are not worthy enough to contest these points. Deal.

But here’s the first problem: physical computing doesn’t have a screen… there are no pop-up windows… no command line… just a bunch of pins that can can read inputs or give outputs… so a blinking or PWM fading LED it is .

So that’s done.

Well that’s damn boring… and I still have a MIGHTY need for “hello world” if only somebody had made up a form of communication that relied on a blinking thing… and MonkeyMorse was born. Quite a simple and not terribly well written program it takes in a string and translates it to morse code and blinks it out. NOW we’re getting somewhere :) (Code Here) First string up: hello world!

So after an implementation of serial communications hello world (Walkthough here) I figured it was time to do something from scratch… the only problem is that I still only had LEDs lying around… and other than making a Knight Rider mod for my car there didn’t seem to be a lot to do with them… until I found PoV.

The basic idea for this project is that if you take an array of LEDs (I have 10 of them) and make them blink while waving them back and forth it will produce an image in the viewer’s eye for a split second. Should that image be the long desired “hello world” so much the better.

As the Arduino has limited processing ability and I wanted the program to switch on and off the LEDs as fast as possible I opted to encode the message BEFORE uploading it to the chip. A decent bit of Matlabbing later and voila! a program to do just that (windows32 standalone program download here) You simply give it a bit of text, point it at a character set (just a bunch of BMPs) and hit go and it does all the work. Additionally: if needed it can be pointed at a bitmap file and instead of doing text it’ll convert the image into code for the MPoV system. Here it is in action:

Moving on: the chip code simply runs though the sequence of bits sent by the converter program and displays them on the LEDs much the same way the signal gets to your TV screen (except that it is essentially sideways and the motion of the board is the major scan direction) The hardware code is also available: MPoV Hardware Code

And the big finish!

…

…

…

Awwwwww…. not as big as I had hoped….

Of note when working with chips and such with on-board hardware: You have VERY limited resources. I’m talking VERY limited. So limited in fact that my lovely 1100 1s and 0s do not actually fit into the memory space. So it can’t be loaded into memory all at one time. A handful of options exist:

1. lower the resolution – Fewer bits = smaller message.
2. Stream the data and get into memory management – Smaller chunks at a time streamed into the processor over a serial connection.
3. Load smaller pieces of the data and possibly make them off of other memory locations – There is a bit of system memory “off to the side” that I might be able to use but this is a little more extreme than I had planned.
4. Just deal with “HiWld!” – Can do RIGHT now.

As you may well have guessed, I went with option 4.

Unfortunately in my glee over a (mostly) working hello world program I failed to actually capture an image of the working final project (and as “Hello World” is supposed to be a quick exercise I’m not going to re-wire it) However I do have this one from a test I ran:

So there you have it. Four ways to hello world and a good deal of fun for an inexpensive-get-your-toes-wet-weekend project. Stay tuned for more madness!

I have seen the light. It was amazing. It never went over 88mph but that’s ok by me. I like it here in this time.

Now to explain the crazy…

Sooo Megan and I are driving back from dinner with Chris and his Megan last night when it happens. The following dialog is completely true and I can only hope to blame it on the immense surge of adrenaline and nerdenaline (yeah, what it sounds like) at the time…

Megan: ::talking while driving::
Jacques: ::looking out the window as 5 lbs of mexican food and a margarita slouch towards Bethlehem::
Jacques: OH MY GOD! CAR! THE CAR!
Megan: Should I turn around?
Jacques: U-turn. U-TURN!!!! BACK THE WAY WE CAME! U-TURN!
Megan: ::Hauls on the wheel. The car hurtles back up the street. ::
Jacques: THERE IT IS! 88 MILES AN HOUR! 88 MILES AN HOUR!!!!

I will now share with you the sight that apparently claimed my adrenal gland, my sense of self-preservation, and my ability to articulate my feelings in full sentences.

The images aren’t great, but you try to get a shot of something so amazing it rips the very fabric of time and metaphor… from a recklessly driven car… at night… with a phone… uphill both ways.

The car from the side. You can see the engine and fission core in the back. The blue glow is a nice touch. That’s right ladies and gents, we’re tailing the time machine from Back to the Future. And it’s amazing.

You can see my shaking hands in the mirror. While you can not tell it from these pictures, I am yelling. I don’t remember what. I’m sure it had 88 miles an hour in it.

I understand it’s hard to see but the little yellow squiggle that you can see through the windshield? Oh yeah, that’s a fully articulated flux capacitor. Streaming little lights and everything.

You can start to see the detail in this car. We followed this guy for 15 minutes. Waaay out of our way. It was totally worth it. This thing had it all. The reactor (old version, not the Mr. Fusion from II and III) the electronics (you could see the date box through the window for setting your “destination”) the blinking lights. It has it ALL.

While the movie car had “OUTATIME” for a license plate, you can’t actually register that as California only lets you have 7 characters. FLUXED is pretty damn good if you ask me. You can also see the fission reactor on the back.

The detail was truly amazing. We ended up losing him right next to universal studios so who knows if it was the real deal but it sure as hell made my night.

Megan and I went joyriding with Doc and Marty :)

88 MILES AN HOUR!

Edit: Sigh… yes, it’s a fission reactor.

But here’s the problem: In the April 2007 issue they were wrong about technology. Not a mere slip or typo but a complete error in an article entitled The “Wii’s Wild Controller” part of a “How It Works” feature.

These types of articles usually interest me as I am a person who avidly disassembles and reassembles gadgets (the latter with a slightly lower success rate). I assume that the people who write them are similarly enthralled with the what the hell does that do? sort of fun that comes along with breaking things open.

Writer Lauren Aaronson promises to explain the inner workings of what the magazine cover calls an “amazing machine.” Sadly, when it came to one of the Wiimote’s crowning features, the screen pointer, Ms. Aaronson not only drops the ball, she lets it roll into the next county. And no one in magazine’s fact-checking department runs after it.

Here’s a scan of the article (with the offending portion blown up for emphasis.)

Aaronson claims that the Wiimote sends IR light to the sensor bar (like a normal remote) where it is picked up and translated into an exact location.

This, my friends, is bull.

I’m someone who has, in fact, taken apart a Wiimote. I’m guessing that Ms. Aaronson does not fall into this category. Perhaps she just read the name “sensor bar” on the package and guessed how the pointer function works. She has, in fact, exactly REVERSED its operation.

The “sensor bar” does not pick up anything. It’s nothing more than a couple of IR LEDs (fancy light bulbs for those of you who didn’t spend your childhood in a RadioShack.) The Wiimote actually has a sensor (think: small camera) in the front of the controller that detects the “sensor bar” position and figures out what the gamer is pointing at. That little camera is what makes it all work.

Not only do I know this, but I can prove it. Look at these two pictures:

Here is the Wiimote with the back off.* The red circle is the unit in question. Sure, it could just be the most advanced LED mount you could cram into the end of the thing, but this next image helps make it clear.

See that? 8 pins! LED’s use 2! Weeelll maybe they use some sort of 7 LED + common ground array (hardly, but whatever)… actually a much more likely story: Those leads connect a camera-like sensor to the Wiimote circuit board.

Even further than pin-counting, further than speculation about LED arrays, further than ill-informed marketing, comes the proof that Ms. Aaronson did not do her homework: You don’t need the so-called “sensor bar”

Yup, that’s right. Take that thing out. (If it were actually a sensor bar your pointer wouldn’t work without it.) Replace the bar with a couple of candles (or the USB powered array that I made for use on my desktop) and prest-o-change-o your Wiimote springs into pointing action!

Observe…

So, PopSci deconstructs something I know about–and they’re wrong? That’s a lot of nerd cred down the drain. Who knows? That “Most Advanced Jet Fighter” on page 48: Does it really run on pixie dust and genetically modified monkeys? Well maybe, but without publication integrity who cares?

Normally the lowest person in a publication chain gets the unfortunate job of fact-checking. But in an edition where the column “From the Editor:” bulges with some serious bragging about their “Wii Broke It” online deconstruction of a Wii, as well as Senior Editor Mike Haney’s great “How It Works” feature, I think the failure is at all levels.

From the Editor Mark Jannot:

Because even if I’m not thrilled that we destroyed a Wii to reveal and document its mechanisms, a am happy that we were motivated by a classically PopSci urge to know–and tell. and I think that you’ll agree that the intel in the How It Works package that Senior Editor Mike Haney and his team have delivered, beginning on page 47, is worth any number of disemboweled videogame consoles.

Well yeah, any number but zero…

If you work for PopSci:
If you want somebody to take things apart: I’m an engineer, graduating from an institution that stresses communication and writing, and I’m looking for a job.

*As I’m not home in CA and able to photograph my Wii at the moment, I snagged a couple of the images from http://www.sparkfun.com/ and added a few red circles for this post.