Do-it-yourself projects and technology updates

Spinning LED Clock

Here is a POV (Persistance of Vision) project that displays a clock. These POV toys have a column of around 7 LEDs. If you spin these LEDs on a motor, and light them all up, you will start to see a solid line of LEDs. Now if you turn the LEDs on and off at the right instant as it is spinning you can display words.

Here is a project that does two cool things in one. First, is a POV toy, but the second is a very good microcontroller project, a clock. Bob Blick made this project using a PIC16F84 chip. He used the crystal oscillator on the microcontroller as his clock signal. This is the same crystal used in digital wristwatches. He then used a motor from a VCR to mount his project on. He gets his power from the windings of the motor.



Bob Blick wrote:…How this clock works:
A motor spins the “propeller”, and a small microprocessor keeps track of time and changes the pattern on seven LEDs with exact timing to simulate a 7 by 30 array of LEDs. It is an illusion, but it works nicely.

If you want to build this clock, you will need a few things, including:
Skill with motors and mechanical things.
Prior electronic experience.
A dead VCR or floppy drive or other source of a suitable motor and miscellaneous parts.
A programmer that will program a PIC16C84 or 16F84 microprocessor….[Link]

This entry was posted on Tuesday, January 24th, 2006 at 11:24 am and is filed under DIY Projects. You can follow any responses to this entry through the RSS 2.0 feed. You can leave a response, or trackback from your own site.