MAX7219
or the MAX7221
There are different solutions for driving this popular piece of hardware from the Arduino. If you are not familiar with the MAX7219
or MAX7221
you should start by reading the hardware related documents
MAX72XX
-datasheet
The software for driving these chips is covered on several pages:
MAX7219
.
Matrix-library
This is the original documentation for the Matrix-library that was shipped with the Arduino software pre Arduino 1.0. The library supports MAX7219
and only works with Arduino 022 and below. To connect multiple MAX7219s together you wire the clk and data to the same lines but the load data line goes to a different pin, also you must define a new matrix and give it a different name.
LedControl-library
Supports the MAX7219
and the MAX7221
. It can drive multiple devices and has a specific command-set for 7-segment displays (besides the common Led matrix functions).
MAX7219
-Library is another available library that supports cascaded MAX7219
's and some basic matrix functions(e.g shiftleft, shiftright, flip, rotate, raise, lower).
Max72xxPanel
library implements Adafruit's GFX
library for multiple 8x8 LED displays driven by MAX7219 or MAX7221, in arbitrary rectangular layout. Support for basic graphic primitives and text. Features double buffering to prevent flicker.
MD_MAX72XX
supports multiple MAX72XX hardware, text functions. and is used by the popular MD_Parola
for advanced text animations display.
More specific problems with the MAX7219
or MAX7221
have been discussed several times on the Arduino Hardware Forums.