Persistence-of-vision, or POV, shows work on the precept that if a lightweight blinks in entrance of your eye, you understand it for some period of time after it’s gone. Blink lights in sequence when shifting, and you’ll create what seems to be like a static picture. “Programmer with a soldering iron” B45i discovered a deal on ATtiny13 microcontrollers for roughly $.30 every, and was capable of create a POV show with one for lower than a greenback.
The construct itself is sort of easy, consisting of an ATtiny13 on perfboard, together with a CR2032 battery for energy, a change, and 5 3mm LEDs. B45i additionally designed a PCB for it, which might presumably put the fee over $1 with delivery, however neatens issues up. This little board can connect to a ceiling fan or different rotational system, blinking away to your programmed sequence.
As there’s no {hardware} to sense the system’s velocity, you could want to regulate delay parameters. One might additionally tweak its visible habits by adjusting the space from its axis of rotation, although one must be careful for unfavourable results on the fan’s steadiness.
Code for this system is discovered right here, which is impressively compact at below 100 strains. A “HELLO 123” string will be modified to show no matter you want, and because it’s written in Arduino C, you can apply it to all kinds of microcontrollers and dev boards. B45i explains the code a bit extra within the undertaking writeup, particularly how he used flagged enums to save lots of processing energy on the restricted ATtiny13 microcontroller.
