A year ago Super Awesome Sylvia demoed MarioChron for the Adafruit MonoChron dekstop clock kit. It’s really neat — once per minute Mario hits the box and receives a coin, so his score is equal to the time. Now thanks to the GPL license on the code, you can carry it on your wrist with the port of MarioChron to the Pebble Smart Watch:

You can install the prebuilt mario.pbw binary and the source is available for further hacking. Here’s a short video of Mario’s coin collecting action (the jump height has since been fixed in the source code).

The code is a straightforward port that reuses almost all of the original logic. The only change is to rearrange the screen slightly from the MonoChron’s 128×64 LCD to the Pebble’s 168×144. This involved translating the glcdClearDot() and glcdSetDot() calls to 2×2 rectangles using the Pebble’s graphics_fill_rect() functions. Unfortunately the e-paper display on the Pebble is designed for mostly static images, and updating it at 10 Hz for the animation draws far more power than a once-per-minute clock face. This means that this watch face consumes lots of power and the Pebble only lasts part of one day instead of an entire week. Perhaps optimizing the redraws instead of redrawing the entire screen would let it last longer.

Want to learn how to write your own watches for the Pebble? Sign up for the May 18 Pebble programming class at NYCR or come to the hackathon after!

Raspberry Pi Model B (512 MB with wired Ethernet) boards are now available in the NYC Resistor vending machine! You can take one home during Craft Night on Thursdays or Laser Night on Mondays. Ask a NYCR member for help with purchasing these awesome embedded Linux boards if you don’t have nine $5 bills on hand since the vending machine doesn’t accept $10 or $20 bills.

Thirty years ago in 1983 the first tablet computer was released: the Tandy / RadioShack TRS-80 Model 100. It ran for weeks on four AA batteries and gathered quite a following. Despite the $1099 ($1399 with extra 8-KB of memory) introductory price tag, features like the built in 300 baud modem with acoustic couplers made them very popular with reporters in the field, and the built-in BASIC programming language (written by Bill Gates himself!) made them easy to adapt into various custom applications. Over six million were produced and as a result, inexpensive, used Model 100s are readily available now. Amazingly many of them still work perfectly and there is a somewhat active Club100 fan club.

I bought one that was non-functional for $20 with the goal of replacing the 80C85 motherboard with a more modern AVR or ARM CPU. While this particular motherboard had failed sometime ago due to bad capacitors, the LCD and keyboard were in perfect working order. Thanks to the combination of the age of the design, the system’s low original clock speed (2.4 MHz) and its 5 V logic make it simple for modern hardware to drive. Moore’s Law also means that the entire motherboard can be shrunk into a PCB with almost zero chips other than the MCU. Read on for what is involved in building a new brain for your Model 100. Continue reading »

I found Matt Joyce’s HDSP211x alphanumeric displays in the LED bin at NYCR and loved the StarTAC style. He had previously written about driving them, but using an Arduino and a shift register on a breadboard was a bit large for my goal of making it into a wristwatch.

I noticed that the PDIP spacing was the same as the Teensy 2.0 and, much like my ROM dumper, hoped that it could fit on the back of the display with almost no additional wires. Read on for the “schematics” and source code details.
Continue reading »

Do you want to be able to control software with interesting things?

Do you want to type text in a weird way?

Do you often need to type just the W-A-S-D and space keys?

Or do you have have ideas for repurposing devices to connect them to your computer? Then sign up for the USB Human Input Device class at NYC Resistor next weekend, 14 October 2012!

The class covers writing firmware for the AVR to implement various USB HID classes, such as keyboards, mice and joysticks, using both raw USB calls and Arduino libraries. Included in the class is a Teensy 2.0, a breadboard and switches for building a simple human input device that you can take home to prototype your next gadget project. Anything with buttons, pedals, sliders or knobs can be used to make an input device once you know how!