My 5 x 5 x 5 Red Green LED Cube

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- 20th January 2011, 21:11
ozarkshermit

My 5 x 5 x 5 Red Green LED Cube

Just thought I'd share this - my latest project.

125 red-green led's in a 5 x 5 x 5 cube. I bought the main circuit board from PIC PROJECTS, but modified it by adding a "piggy-back" board with a PIC18F2520, running at 32 MHZ on its internal oscillator. Slightly more than 24k bytes , over 3000 lines, using PBP 2.6 . I'm sure it can be reduced, when I "get better" .

Side note - Green Bay Packer fans will enjoy seeing it, Chicago Bears fans might not . . . .

See it here on You Tube
http://www.youtube.com/watch?v=WDfJ_bOeWyQ

Ken
- 20th January 2011, 21:42
mackrackit

COOL!!!

This would make a good project for the wiki if you want to tell more about it.

Side note... Are the Packers a trucking company hauling Bears???
:)
- 21st January 2011, 16:50
ozarkshermit

Thanks Dave

Here are a few more details . . . As I mentioned, I purchased the main circuit board from PICPROJECTS, (an excellent board by the way, my only complaint would be the size of the pads). You are probably familiar with him - he offers several kits, etc. Since I wanted to do my own software (in PBP of course) , and wanted a lot more flash memory than the 16f688 has, I opted for the 18f2520. On a first prototype I had included a 7805 with related parts for the
5V power, but later decided to just use a 5V wall wart directly. I etched a small board for the 18F2520. It connects with only 5 wires, + and ground, and wires for Data, Clock, and Latch for the STP16CP05's. It only has a few resistors and decoupling caps, and I added a connecting socket for ICSP as well. In addition, I used two UDN2981's on the board for LED source drivers rather than individual transistors (10 required). Making the actual cube took a lot of careful soldering, but there are a number of websites showing various assembly techniques and templates to arrange the LED's.

My software obviously works, but someone like you could no doubt make several improvements. The software could be simplified if only single color LED's were used. It still was not very complicated for the most part. I am not using any interrupts, I found that I could easily get by using for-next loops with pauses for any of the multiplexing required, since the PIC is running at 32 MHZ. I made extensive use of lookup2 tables (25 bits are needed for the LED patterns), and lots of subroutines, plus a gazillion constant definitions for the various patterns, rather than typing in the hex value all the time.

I would be happy to try to answer any questions you might have.

Ken
- 21st January 2011, 18:50
mackrackit

I bet there are several folks that would like to see the code and schematic if you did one.
Here would be a good place to put this project.
http://www.picbasic.co.uk/forum/content.php?r=36

Yes, I am trying to get users to use the wiki more, projects like this end up buried in the regular forum after awhile.

Quote:

My software obviously works, but someone like you could no doubt make several improvements.

Probably not. It works like you want it to so why mess with it???

Quote:

I made extensive use of lookup2 tables (25 bits are needed for the LED patterns), and lots of subroutines, plus a gazillion constant definitions for the various patterns, rather than typing in the hex value all the time.

:) Sorta like the "missing functions" some complain about... I like the sounds of it.
- 21st January 2011, 19:25
cncmachineguy

Quote:

Originally Posted by mackrackit

I bet there are several folks that would like to see the code and schematic if you did one.
Here would be a good place to put this project.
http://www.picbasic.co.uk/forum/content.php?r=36

I am intrested.