Here's another shot of how I breadboarded everything for prototyping purposes.
I wrote a simple program to run on the Trinket, based on the Adafruit strandtest program. It's not the cleanest, but I didn't have a lot of time before EDC and it looked really great.
Here's the code I came up with based on the strandtest program (also on Github):
#include "Adafruit_WS2801.h"
///include "SPI.h" // Comment out this line if using Trinket or Gemma
#ifdef __AVR_ATtiny85__
#include <avr/power.h>
#endif
/*****************************************************************************
Example sketch for driving Adafruit WS2801 pixels!
Designed specifically to work with the Adafruit RGB Pixels!
12mm Bullet shape ----> https://www.adafruit.com/products/322
12mm Flat shape ----> https://www.adafruit.com/products/738
36mm Square shape ----> https://www.adafruit.com/products/683
These pixels use SPI to transmit the color data, and have built in
high speed PWM drivers for 24 bit color per pixel
2 pins are required to interface
Adafruit invests time and resources providing this open source code,
please support Adafruit and open-source hardware by purchasing
products from Adafruit!
Written by Limor Fried/Ladyada for Adafruit Industries.
BSD license, all text above must be included in any redistribution
*****************************************************************************/
// Choose which 2 pins you will use for output.
// Can be any valid output pins.
// The colors of the wires may be totally different so
// BE SURE TO CHECK YOUR PIXELS TO SEE WHICH WIRES TO USE!
uint8_t dataPin = 1; // Yellow wire on Adafruit Pixels
uint8_t clockPin = 2; // Green wire on Adafruit Pixels
// Don't forget to connect the ground wire to Arduino ground,
// and the +5V wire to a +5V supply
// Set the first variable to the NUMBER of pixels. 25 = 25 pixels in a row
Adafruit_WS2801 strip = Adafruit_WS2801(15, dataPin, clockPin);
// Optional: leave off pin numbers to use hardware SPI
// (pinout is then specific to each board and can't be changed)
//Adafruit_WS2801 strip = Adafruit_WS2801(25);
// For 36mm LED pixels: these pixels internally represent color in a
// different format. Either of the above constructors can accept an
// optional extra parameter: WS2801_RGB is 'conventional' RGB order
// WS2801_GRB is the GRB order required by the 36mm pixels. Other
// than this parameter, your code does not need to do anything different;
// the library will handle the format change. Examples:
//Adafruit_WS2801 strip = Adafruit_WS2801(25, dataPin, clockPin, WS2801_GRB);
//Adafruit_WS2801 strip = Adafruit_WS2801(25, WS2801_GRB);
void setup() {
#if defined(__AVR_ATtiny85__) && (F_CPU == 16000000L)
clock_prescale_set(clock_div_1); // Enable 16 MHz on Trinket
#endif
strip.begin();
// Update LED contents, to start they are all 'off'
strip.show();
}
void loop() {
// base
colorWipe(Color(255, 0, 0), 50); // red
rainbow(2);
colorWipe(Color(0, 255, 0), 50); // green
rainbowCycle(2);
colorWipe(Color(0, 0, 255), 50); // blue
rainbow(2);
colorWipe(Color(255,0,255), 50); // magenta
rainbowCycle(2);
colorWipe(Color(255,140,0), 50); // orange
rainbow(2);
// now let's go slow
colorWipe(Color(255, 0, 0), 100); // red
colorWipe(Color(255,140,0), 100); // orange
colorWipe(Color(255,255,0), 100); // yellow
colorWipe(Color(0, 255, 0), 100); // green
colorWipe(Color(0, 0, 255), 100); // blue
colorWipe(Color(255,0,255), 100); // magenta
// base again..
colorWipe(Color(255, 0, 0), 50); // red
rainbow(2);
colorWipe(Color(0, 255, 0), 50); // green
rainbowCycle(2);
colorWipe(Color(0, 0, 255), 50); // blue
rainbow(2);
colorWipe(Color(255,0,255), 50); // magenta
rainbowCycle(2);
colorWipe(Color(255,140,0), 50); // orange
rainbow(2);
// now let's go fast!
colorWipe(Color(255, 0, 0), 10); // red
colorWipe(Color(255,140,0), 10); // orange
colorWipe(Color(255,255,0), 10); // yellow
colorWipe(Color(0, 255, 0), 10); // green
colorWipe(Color(0, 0, 255), 10); // blue
colorWipe(Color(255,0,255), 10); // magenta
}
// fill the dots one after the other with said color
// good for testing purposes
void colorWipe(uint32_t c, uint8_t wait) {
int i;
for (i=0; i < strip.numPixels(); i++) {
strip.setPixelColor(i, c);
strip.show();
delay(wait);
}
}
void rainbow(uint8_t wait) {
int i, j;
for (j=0; j < 256; j++) { // 3 cycles of all 256 colors in the wheel
for (i=0; i < strip.numPixels(); i++) {
strip.setPixelColor(i, Wheel( (i + j) % 255));
}
strip.show(); // write all the pixels out
delay(wait);
}
}
// Slightly different, this one makes the rainbow wheel equally distributed
// along the chain
void rainbowCycle(uint8_t wait) {
int i, j;
for (j=0; j < 256 * 5; j++) { // 5 cycles of all 25 colors in the wheel
for (i=0; i < strip.numPixels(); i++) {
// tricky math! we use each pixel as a fraction of the full 96-color wheel
// (thats the i / strip.numPixels() part)
// Then add in j which makes the colors go around per pixel
// the % 96 is to make the wheel cycle around
strip.setPixelColor(i, Wheel( ((i * 256 / strip.numPixels()) + j) % 256) );
}
strip.show(); // write all the pixels out
delay(wait);
}
}
/* Helper functions */
// Create a 24 bit color value from R,G,B
uint32_t Color(byte r, byte g, byte b)
{
uint32_t c;
c = r;
c <<= 8;
c |= g;
c <<= 8;
c |= b;
return c;
}
//Input a value 0 to 255 to get a color value.
//The colours are a transition r - g -b - back to r
uint32_t Wheel(byte WheelPos)
{
if (WheelPos < 85) {
return Color(WheelPos * 3, 255 - WheelPos * 3, 0);
} else if (WheelPos < 170) {
WheelPos -= 85;
return Color(255 - WheelPos * 3, 0, WheelPos * 3);
} else {
WheelPos -= 170;
return Color(0, WheelPos * 3, 255 - WheelPos * 3);
}
}