The seven-segment display which is also an input device

We're used to seeing all kinds of seven-segment displays, whether mechanical, electronic, or something in between. But what all of these screens have in common is that they are, you know, screens. Using them as inputs would just be crazy talk, wouldn't it?

Maybe, but we like where [Dave Ehnebuske] is going with "InSlide," the seven-segment input device. The idea comes from the "DigiTag" display, which we covered in October, and divides a standard seven-segment character into three vertical bands - two thin for the outer vertical segments and a wide band containing the horizontal elements. By sliding these strips up and down relative to each other, the standard nine digits, plus a few other characters, can be dialed.

[Dave's] take on this theme started by building his display out of laser cut plywood pieces, which is a good choice due to the good contrast between the white wood and the etched segments . Then he embedded rare-earth magnets in the slides and installed seven Hall-effect sensors in the frame. The sensors are connected to an Arduino Nano via a 74HC165 parallel load shift register, which allows multiple modules to be daisy-chained. He also built an Arduino library to read the current state of segments; it supports the full hex character set, or even duodecimal if desired.

[Dave] shared the library and it looks like you can get the mechanism build files from the original project. That's good, because it seems ripe for hacking. It looks like it would be quite easy to motorize a display like this by adding cog gears and steppers - something like that could make an interesting clock.