Micah Elizabeth Scott (scanlime) writes about hardware hacking and electronics projects, including RFID, LED controllers, Nintendo DSi debugging, and a path tracer.
Commenters praise her portfolio as amazing, and cite her DSi work as an example of reading RAM without costly debuggers.
Speaking of homemade RFID tags, a couple impressive hacks.
1. Micah Elizabeth Scott built a working RFID tag using just two parts: an ATTiny85 micro controller and a small inductor. The two leads of the inductor are soldered directly to two I/O pins of the processor.
That is the only connection to the processor. The power and ground pins are not connected. The processor gets power via leakage current from the I/O pins. It gets clocked from one of those I/O pins, too.
https://scanlime.org/2008/09/using-an-avr-as-an-rfid-tag/
2. Here's another one of hers, this time with a coil made from magnet wire, and with fancier mounting. The coil, processor, and this time a couple of tuning capacitors, is squished onto duct tape and sealed with clear packing tape.
https://scanlime.org/2011/05/duct-tape-rfid-tag-1/
3. Trammell Hudson made use of her antenna and processor only design for a project of his, which has a pretty good write up.
https://trmm.net/AVR_RFID
> But taking advantage of that feature requires a five-figure-priced JTAG debugger
Reading RAM in a running system (even a "hardened" one) is easier than most think. Micah Elizabeth Scott's work on the Nintendo DSi [1] is an excellent example: with a budget of just $500 and a month or two of work [2] she could read a video stream out of RAM as it was being DMAed to/from the camera [3].
I can't even begin to describe how impressed I am with Micah's work, but cloning her FPGA tool from GitHub [4] and repeating the feat for a relatively static segment of executable code on a system that's less physically hardened against tampering, that seems trivial to me in comparison. Certainly doable with $500 and a couple of weeks time.
1. http://scanlime.org/2009/09/dsi-ram-tracing/
2. https://twitter.com/scanlime/status/562925122106191873
3. http://hackmii.com/2009/09/dsi-ram-tracing-camera/
4. https://github.com/scanlime/ram-tracer
Pretty.
I had obviously expected that, but the large number of reflective surfaces [1] greatly reduces the performance. The author explained in the blog post [2] that it is a path tracing (Monte Carlo simulation of multiple random rays incrementally averaged) and probably it is hard to limit the number of bounces small while maintaining the image quality. Indeed, the source code [3] says a hard limit of 1000 bounces, not big but not that small either.
[1] Something like http://is.gd/cFDlq5
[2] http://scanlime.org/2013/04/zen-photon-garden/
[3] https://github.com/scanlime/zenphoton/blob/bea23c1/hqz/src/zrender.cpp#L329
I guess my comments make it sound like I don't appreciate this type of work; I absolutely do. An old friend of mine[1] was responsible for the first 3d support in the vmware svga driver, so this is a space I have been following for literally decades at this point.
I just think it should be the objective of vendors to offer actual GPU virtualization first and to support paravirtualization as an optimization in the cases where it is useful or superior and the tradeoffs are acceptable.
[1] https://scanlime.org/
Heres a project I read about recently that uses a Parallax Propellor to get high speed multi core computing out of a micro controller project - I'll probably give one of these a whirl if/when I need more cpu horsepower than I can get out of the regular line of Arduino hardware:
http://scanlime.org/2011/04/spdif-digital-audio-on-a-microcontroller/
See also FadeCandy by Micah:
https://scanlime.org/2013/11/fadecandy-easier-tastier-and-more-creative-led-art/
> Firmware that uses unique dithering and color correction algorithms to raise the bar for quality while getting out of the way of your creativity.