so a while ago i set out to make a POV toy for a bicycle, much like ladyada and many other people have done. im going to use serial-to-parallel shift registers, and all surface mount parts, which makes my job a lot easier.
so first i designed the board. i posted them a while back, i wont bother with them again. of course, it later turned out to have some bugs, but i didnt expect it to be perfect.
i etched it using the laser printer method, and it came out really well. it was amlost perfect, and i was really happy with myself. so i proceeded to solder the parts on, which are
- 8 surface mount super-bright red leds
- 2 16SOIC quad transistors
- 1 16SOIC shift register
- 16 surface mount resitors
- 4 jumper wires.
it should be noted that my soldering iron is broken, so i was using a 140 watt weller iron with the tip filed to a point.
so i got that all together, and i was about to test it when i realized that i had forgot to compensate for the mirroring effect of he laser printer mehod - i had a mirror image of the board i wanted! so i had to take of the 3 SOIC chips, bend the pins, and put them back onto the board upside down! haha. i sure showed it.
i hooked it up to a 16f767 PIC, and with a few likes of code (about 300 to be exact... i wasnt trying to be efficient
) , i had it displaying a 20 column picture with 10ms between columns. it wasnt very hard at all. heres what it looks like:
well you get the point. heres two other real crappy pictures from my crappy webcam.
so now the next step is to put it on a bicycle wheel. and add a sensor... and completely rewrite the code... ill be done in a month maybe
(oh, its also running off a 9V battery going through my old 3.3v TI DC-DC converter. i think that this is neat)
and the current draw, for all you concerned about battteries is about 105mA @ 3.3v. i project that a whole bicycle wheel would take about 400mA
