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Articles in the Electronics Category

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[29 Jun 2009 | 2 Comments | ]
Cloud Convergence; A Vision of the Perfect Cell Phone/Mobile Device

We’ve reached a point now where smartphones are ubiquitous. I myself have a Blackberry Curve, the iPhone 3Gs is out, the Palm Pre is there and by summer’s end a number of Google Android powered phones are expected.
So far the trend has been to build more and more computing power into the devices so they can run plenty of applications. That’s not where things are headed though.
Switching gears for a second back to traditional Desktop computing: Pano Logic [LINK] make a tiny little box that completely virtualizes the computer. …

Electronics, Featured, General Computing, Headline, Weird Wide World »

[29 May 2009 | 2 Comments | ]
What Can The Big Mess o’ Wires Teach Us About Software?

Steve Chamberlain [LINK] has achieved the ultimate in home-brew electronics: Creating his own CPU from basic logic chips. Absolutely amazing. The photos alone are a thing of beauty but to know this thing actually works is incredible.
From Steve’s site:
“Big Mess o’ Wires 1 is an original CPU design. It does not use any commercial CPU, but instead has a custom CPU constructed from dozens of simple logic chips. Around this foundation is built a full computer with support for a keyboard, sound, video, and external peripherals.
My original goals were:

Build the …

Electronics, Featured, Headline, Things I've Made »

[14 May 2009 | 78 Comments | ]
How to Build a 8×8 RGB LED Matrix with PWM using an Arduino

A while ago I designed a circuit that would power an 8×8 RGB LED Matrix (192 LEDs in all) using only 3 pins from an Arduino Diecimila and supporting Pulse Width Modulation. I’ve uploaded some videos of this project on Youtube and folks have been emailing me with questions on how it works. In this post I’ll try to answer all those questions so you can build your own.
I started with the LED Matrix component itself. I used an RGB 8×8 common anode matrix from LedSee (only $10 on ebay). …

Electronics, Featured, Science »

[8 Mar 2009 | 8 Comments | ]
What Are Pull-Up and Pull Down Resistors?

The terms “pull up” and “pull down” resistors confused the heck out of me but I get it now.
A resistor limits current. In the water analogy, current is the speed of the flow of water. But I never knew what a pull up/pull down resistor was. Until a few weeks ago when I started building a set of buttons for a project I’m working on…
Essentially a button is a switch, when the switch is closed the current flows, when it’s open the current doesn’t flow. Now if your switch is …

Electronics »

[27 Jan 2009 | No Comment | ]
Curious Inventor giving away Free Stuff

Curious Inventor (http://www.curiousinventor.com) is offering a free "PanVise Junior Clamp" at the moment if you link to them. So here goes [LINK].
Last night I got an email from Shawn over at [http://www.arduinofun.com/]. Shawn’s built a cool robot using various bits and pieces, including the arduino with Curious Inventor as his supplier. The coolest thing about this is he’s built it with his 11 year old son Drew. This is great on so many levels and I can’t think of anything better than mentoring a child in this manner.
I …

Electronics, Featured, Science, Things I've Made »

[4 Jan 2009 | 3 Comments | ]
Science is Wonderful

Kids are like giant sponges. I finally got my Arduino powered RGB LED Matrix soldered together and firing on all cylinders last night. I wrote a simple interface in Processing and then showed the kids after lunch today. Within about 30seconds they were having fun turning on and off lights. Here’s the result:

They saw how things were linked together, how a click on the screen lit a dot on the matrix and it was simple enough but yet they could quickly make shapes and letters. They got a …

Electronics, Featured »

[21 Dec 2008 | One Comment | ]
Arduino RGB LED Matrix Prototype

My latest tinkering: An Arduino throwing data at a couple of shift registers that in turn power an 8×8 RGB LED matrix. I’ve only hooked up half of blue and red right now to get the multiplexing/programming right. Never done this before and it’s rather confusing. Right now it’s working with red, blue and Purple. I’m limited to 6+1 colors, not sure how to get more since I don’t think I can do pulse width modulation through a shift register. It’s fun so far.

Electronics »

[7 Dec 2008 | 7 Comments | ]

Here’s an Arduino [LINK] connected to a 4×20 HD44780 display, enclosed in 8"x4 1/2" Lexan.
I used a modified version of the LCD arduino library and hacked the LCD Smartie Sketch using Orbital Matrix commands.
LCD Smartie is running the BigNum plugins. It shows Facebook news feeds, BBC Headlines, a Clock, local Weather and my Folding at home status (team 144824) among other things.
This was a fun project, not too much soldering and had a high reward vs time invested.
Here’s a video of the finished product.

Cool & Future Tech, Electronics »

[14 Aug 2008 | No Comment | ]

My contract’s almost up and the search is on for a new cell phone. I’ve had a fairly basic phone up until now and don’t pay it much heed. In the last two years though the iPhone has come out and despite some major shortcoming’s its pretty cool.
Battery life sucks though and I couldn’t take signing up to iTunes just for phone access. That’s uncalled for. So what’s the competition? Verizon have some fairly blech looking clones (the LG Dash) but what I’d really like is an HTC device …

Electronics, Things I've Made »

[25 Feb 2008 | No Comment | ]

As the Arduino only supports 14 output digital pins, I ordered some shift registers a while back from eBay. They took 7 days to arrive but are finally here.
As a small project to get my feet wet with serial/parallel output, shift registers etc. I’ve set about building a 25 (5×5) RGB LED matrix display. I may extend it in the future to 7×5 for larger fonts.
I’m using circuit board from RadioShack to which I’m soldering the LEDs. I intend on using breadboard for the chips until I get …