The magic wand clock: yet another POV !
This project has a few years already and sat in a box until recently. I cleaned it up, took some picture commented the code and decided to make this instructable. I hope you’ll enjoy it as much as I enjoy sharing it with you.
As I read somewhere – I would like to give credit – : " it is not fun until you share it ".
Now, the thing. This is a persistance of vision project of the kind we have seen lately in large quantities. POVs are fun to watch anyways. This one comes in the shape of a tooth brush case (courtesy of Swissair, now gone) one must hold as a magic mand. At the top of the case 7 LEDs provide the display, at the middle two small button set the time and a larger one triggers the display: push the button and swing the wand right to left and the time of day will float midair !
The circuit apart from the parts already cited, is based on a PIC16F84 micro, a 32768 Hz crystal watch salvaged from a dead watch 8 resistors, two capacitors and two AA or AAA batteries.
The circuit consumes very little power due to the low voltage supply and the low frequency crystal.
Synchronizing button push and wand swing may take time to learn, but not much.
Further details at http://5volt.blogspot.com/ .
The time is set with trials and errors: read the time, push minutes set button to meke them advance one minute per second, read time again. The same to set hours.
Below the schematic, the source code commented so as to make it understandable as much as possible and the HEX file ready to burn into the PIC.
I’d rather not delve into how to program the micro. There are many tecniques and sofware described over the net. This would probably deserve a whole instructable of itself. I successfully used PonyProg as programming software and its HW interfaces. Also found excellent WinPIC.
Make sure to check the video attached at the bottom. The quality is not good being taken with a photographic camera. The clicking noise is the ‘wand!’ button being clicked while swinging. The voices in the background are my family’s.
Now on with step one: construction
This work is licensed under a Creative Commons Attribution-Noncommercial-Share Alike 2.5 License
More: continued here