Enigma QR Clock

Inspired by this article:
http://hackaday.com/2012/10/29/qr-clock-is-unreadable-by-humans-and-computers-alike/

A QR generation library was ported to the Arduino UNO and Seeed LCD touchscreen platform. Originally the generation time was 6 seconds, making the display of seconds impossible.

As @ch00ftech suggested, eliminating the search for the optimal QR mask and instead applying a fixed mask, drops the generation time to less than one second.

Using a fast TFT display library by @Xark allows seconds to be displayed. This library was modified to comply with the calling convention for @seeedstudio libraries, making it a drop in replacement in an existing sketch. By changing a compiler directive, this library can also control an @adafruit LCD.

As a further optimization, the last QR code generated is stored in a bitmap so only the pixels that change are painted.

Components

1 × Arduino Uno
1 × Seeed LCD v2.0 or Adafruit LCD
1 × Laser cut case

Project Logs

Collapse logs

QR Code background can now be inverted.
Arduino Enigma • 09/30/2016 at 10:58 • 0 comments

It was reported that some (citation needed?) apps were unable to decode the default QR background. The i command was introduced to flip the color of the QR code. Updated code is at Github.
https://github.com/arduinoenigma/EnigmaQRClock
New Inverted view:
Original view: