Difference between revisions of "ChromoDisk"

From i3Detroit
Jump to: navigation, search
m (Added hardware and software source files.)
m (Added more improvements)
Line 15: Line 15:
  
 
Notes on Improvements:
 
Notes on Improvements:
1. Improve power distribution.  RESET pull-up is at the end of the line.
+
#Improve power distribution.  RESET pull-up is at the end of the line.
2. Polarity of battery holder is reversed.
+
#Polarity of battery holder is reversed.
3. Add ground plane
+
#Add ground plane.
4. Pull-up on SCLK line affects programming
+
#Pull-up on SCLK line affects programming.
 +
#Need to current-limit base drive on Q1-Q9, else overheats CPU.
 +
#Add 220uF cap to power supply to avoid programming problems.

Revision as of 13:01, 14 November 2011

The ChromoDisk aka ColorMesh v1

... is a round PC board with 9 rings of 18 RGB LEDs each. The microcontroller and other components that make it work are in the center. The design is based upon the [Aurora Instructable]. Since I've worked with AVRs, and this seems like an interesting introduction to PCB design with LEDs, I decided to redo the original to fit into a 100mm dia board for minimum cost. I also designed it for a AA battery pack on the back side of the board. We'll see how long it lasts with 162 LEDs!

Current status: Boards in, first prototype done (5 hours to assemble!), writing software for it. Here's a demo of a simple program I wrote:

Demo of prototype

File:Chromodisk1.sch

File:Chromodisk1.brd

File:ColorTest1.asm

File:ColorMesh.asm

Notes on Improvements:

  1. Improve power distribution. RESET pull-up is at the end of the line.
  2. Polarity of battery holder is reversed.
  3. Add ground plane.
  4. Pull-up on SCLK line affects programming.
  5. Need to current-limit base drive on Q1-Q9, else overheats CPU.
  6. Add 220uF cap to power supply to avoid programming problems.