Arduino library for Adafruit 16x32 and 32x32 RGB LED matrix panels. http://www.adafruit.com/products/420 http://www.adafruit.com/products/607
Adapted for Spark by Paul Kourany, June 2014
Updated for Particle Photon, Sept 2015
Updated Dec 2015 to properly support wide or daisychained panels with a "width" parameter. Thanks to Andrew Holmes (author of RGBPongClock) for this contribution!!
Confirmed compatible with Electron, May 2016 Updated examples for new v4 RGBMatrixPanel shield pinout, May 2016
Add delay() in loop() to animation examples to improve effects, Dec 2016
The Photon version only uses bit-banging due to the GPIO pin mapping not allocating enough pin on a single port. However, with the Photon's 120MHz clock, the refresh rate is 140Hz
The orginal Arduino library used a lot of direct I/O port write tricks and assembler to achieve a calculated 283Hz refresh rate for a 16x32 panel.
The Particle version comes in two flavours: bit-banging and (partial) port write for the output which could be optimized using inline assembler. As it stands the calculated refresh rate for a 16x32 panel using the bit-banged version is 90Hz while the (partial) port write version is 140Hz (half those values on 32x32 panel).
The library supports 16 pixel high and 32 pixel high panels of any multiples of 32 pixels wide. Adafruit sells 16x32, 32x32 and 64x32 panels fully compatible with the library. Daisy chaining displays will also allow for wider configurations, limited only by available Core, Photon or Electron RAM.
Constructor examples:
RGBmatrixPanel matrix(A, B, C, CLK, LAT, OE, true); //16x32 panel, width is 32 by default if not specified
RGBmatrixPanel matrix(A, B, C, CLK, LAT, OE, true, 64); //2 x 16x32 daisy chained = 16x64 panels
RGBmatrixPanel matrix(A, B, C, D,CLK, LAT, OE, true, 32); //32x32 panel
RGBmatrixPanel matrix(A, B, C, D,CLK, LAT, OE, true, 64); //64x32 panel
This library requires the Adafruit_mfGFX and SparkIntervalTimer libraries
Wiring between the Spark and 16x32 or 32x32 display is as follows:
Panel Pin Core Pin Photon/Electron Pin
--------------------------------------
GND GND GND
CLK D6 D6 // Specified in constructor
OE D7 D7 // Specified in constructor
LAT A4 A4 // Specified in constructor
A A0 A0 // Specified in constructor
B A1 A1 // Specified in constructor
C A2 A2 // Specified in constructor
D A3 A3 // 32x32 display only - Specified in constructor
R1 D0 D0
G1 D1 D1
B1 D2 D2
R2 D3 D3
G2 D4 D4
B2 D5 D5
The display needs its own 5V supply.
Connect, compile, flash and run.