Digirule 2: Ruler and Binary Computer in One

In the 1970s, you could have your own personal computer; however, systems such as the Altair 8800 didn’t feature a rudimentary TV-like screen and keyboard, but instead the interface was through a series of dots and switches. While some might not even recognize this as a computer today, it allowed one to input programs in binary form, and gave many hours of entertainment and frustration to those brave enough to explore this new world.

Today, 40 years later, you can literally wear a computer exponentially faster on your wrist, but there’s still something interesting and educational about this 8-bit binary experience. The good news is that as computing has advanced, the price of such binary systems can be made very low, so low — and compact — that the Digirule 2 embeds an entire binary computer on an otherwise normally-sized ruler. In fact, the button and light arrangement on a ruler like this actually makes a fairly good user interface.

Based on a PIC18F43K20 MCU, the Digirule 2 can be configured to perform all sorts of tasks via a simple instruction set and programs can easily be saved and loaded back up thanks to its internal EEPROM.

To help you get started, the device also comes with an Excel spreadsheet that converts commands into binary as needed. You just have to push quite a few buttons to input everything! Following along with the binary theme, the ruler displays length in 1s and 0s as well, which shouldn’t be a problem after tinkering with its interface for any amount of time!