Arduino vs Raspberry PI

Ok - so I'm new to this - The Raspberry Pi got a lot more press than the Arduino and I jumped on board the Raspberyy Pi train without knowing the options.

My goal was to build a doorbell to solve the problem of not hearing it in all parts of the house (3 stories).

I followed this blog

GNU Toolchain Cross-Compile Challenges

For the last several days I've been working to compile the latest free GNU Toolchain for ARM published by CodeSourcery (now owned by Mentor Graphics).

This process has not been easy.  In this lengthy blog post, I'll share all the patches I've written, with detailed explanations of exactly what errors I encountered, what I've learned about each problem, and how to work around it.

Edit: full source is on github.

"Read mode" for all the gory details......

Input & Output Analog/Digitial Pin Test Circuit

I wanted a board that shows the state of all I/O pins on LEDs with all of these properties....

  • Works for Digital Input, Output, and Input Pullup
  • Pushbutton to drive the pin high, very weak pulldown (much weaker than on-chip pullup)
  • Works for analog pins (thumbwheel pot), but also works when the same pin is used for digital
  • LED shows actual analog level - LED current should be linear to actual voltage
  • LED current does not interfere with analog voltage
  • LED does not interfere with weak signals, or input pullup or pulldown
  • Inexpensive - under $0.50 per pin - many parts are ok, as long as they're cheap!

"Read More" for the circuit details and photos.....

Composition for Balloons and Electronics

A few months ago Charles Buckingham told me about a crowd participatory composition idea he had where every person in a large crowd would have a smart phone that made sound which they could control, to some extent, that combined would form a work of music. After we together made several iterations on the idea: reinterpretations, misinterpretations, experimentation, research, etc. the project became a composition idea for a crowd participatory experiment using home made mylar balloons making buzzing tones and clicking sounds with pizeo transducers, lit up with RGB LEDs and finally popped with model rocket igniters and gun powder.

I go into a lot more detail here:

Video of my talk at Teuscher Lab.

Here's the video for the talk I gave on Tuesday.  I give an overview of Dorkbot and DorkbotPDX and discuss the kinds of things we do.



Slides from today's Nuts and Bold Dorkbot talk

I gave a talk today at Christof Teuscher's Nuts and Bold Seminar about DorkbotPDX and what we've been up to.  The slides are available here:

or for those who don't do google:

Thanks to everybody who showed up and contributed!

Test post, using images.

There are some images here....

LCD ARM board status update

After moving twice this summer, I finally got my workbench set up again (at least enough to start building stuff again). So I was able to build the latest version of the LCD ARM dev board ( It works fine and I think all the errors from the previous version are fixed. So I've attached the Eagle files and the BOM.

Trying out a new editor


I'm trying out a new drop in replacement editor for Drupal.  Trying to get my head around what this means and what to think about it, but I think it's mostly good.

LED Video Wall


Several months ago, I was approached by the Portland band Starfucker (STRFKR) to build them an LED video wall for their upcoming tour. It needed to be large, bright, and durable, but also lightweight, portable, and easy to set up and tear down. They wanted to be able to plug in an iPod or iPad and play videos that are synced up along with their click track so everything goes along perfectly with the music. I enlisted the help of Alex Norman to take care of the software side of the project, and got to work trying to figure this thing out. It seemed like it could be made with mostly off-the-shelf components, and indeed that turned out to be the case. We decided that we would open-source the entire project, for the good of all mankind.


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