Learn to drive flip-disc shows together with your Arduino

Earlier than digital show expertise grew to become reasonably priced and sensible, electromechanical flip-disc (AKA “flip-dot”) shows had been a preferred alternative due to their excessive visibility and talent to scale to massive sizes. For all sensible functions, flip-disc shows have been out of date for many years. However we’re seeing a resurgence in demand for them, as they’ve a beautiful and nostalgic attraction. Should you’re all for utilizing them, Marcin Saj has an excellent tutorial explaining the way to management a flip-disc show with an Arduino.

A part of the rationale that flip-disc shows are onerous to seek out as we speak is that they’re electromechanical gadgets that require devoted manufacturing. Every “pixel” is a bistable machine that can stay in its set place till the consumer actively resets the place. To flip the disc, the consumer should provide a pulse of electrical energy by way of an electromagnet coil within the appropriate polarity. One path units the disc to at least one aspect, and the reverse polarity units the disc to the opposite aspect. As a result of the discs are bistable, the consumer solely must flip the mandatory discs to realize the states they require — not the complete show. Flip-discs are comparatively sluggish, so that’s essential for lowering total refresh time.

Saj’s tutorial goes into depth on these management methods utilizing a customized driver board with a 595D shift register and an H-bridge. The shift register reduces the variety of Arduino I/O pins required for management by setting the states of the discs one after the opposite. The H-bridge is a set of interconnected switches that makes it simple to reverse the polarity of a portion of a circuit, which is the lively disc on this case. By storing the states of the discs in reminiscence, one can skip over the discs which might be already within the correct state and save time.

This tutorial is supposed to work with Flipo.io’s personal flip-disc shows and drivers, which had been designed particularly to be used with Arduino boards and that might be launching quickly by way of Kickstarter. The tutorial focuses on a three-disc show, however it seems that Flipo.io intends for customers to broaden that into bigger preparations.