Current Status

A project log for NoteOn Smartpen

Slim, wireless, self-contained. No special paper, no base station.

nick-amesNick Ames 08/21/2014 at 04:500 Comments

As of 2014-08-20, the electrical and mechanical design of the NoteOn prototype is complete. One case and two PCBs have been manufactured. 

The first PCB, prototype 1, was damaged by a static shock which disabled its crystal oscillator, so I've been using prototype 2 for development. Unfortuneatly, prototype 2's auxilliary accelerometer doesn't work. (It responds over I2C, but the acceleration readings are always pegged to their maximum value. Checking against prototype 1's working aux. accel shows that the software is not at fault.) I've purchased a replacement accelerometer, and will swap it in once I can aquire a hot air rework tool. All other parts of prototype 2 appear to work fine.

Development on the device firmware is ongoing. The board has been brought up, and I've written drivers for all nessecary internal peripherals, excluding USB. Drivers for the battery monitor IC and external flash memory have been written and tested. I'm currently working on a streaming driver for the IMU. (The driver will stream data continuously from the IMU, with the IMU caching its data in its internal FIFO between reads.) After that's done, I plan on getting Bluetooth communication working.