LedControl. A arduino library for the MAX7221 and MAX7219 These two chips provide an easy way to control either an array of 64 Led's or up to eight digits made of 7-segment displays with a minimum of electronic components. Besides the chip itself you will need only a single resistor and one or two capacitors. Data is send to the chip using a SPI-compatible protocol using 3 of the digital pins on the arduino. If you want control more than eight 7-segment displays (or more than 64 Led's) the chips can be cascaded. The library supports up to 8 cascaded devices, which add up to 512 Led's that can be lit individually. The good news is that you still need only 3 pins on your arduino board. Here is a picture of my rather crappy (but working) testbed... If you wonder wether the MAX7221 or the MAX7219 is more suitable for your project ... just go for the cheaper one. Everything else you need to know about the MAX7221 and MAX7219 is to be found in the components datasheet.
Table of Contents Power saving mode. Playground - LEDMatrix. 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 The MAX72XX-datasheet The The MAX7219 and MAX7221 Led drivers article, with schematics and some additional information related to the Arduino. Multiplexing the MAX72xx to drive a 2 Color Matrix - using an alternating shutdown method to control a 2 color matrix with 2 MAX72xx. The software for driving these chips is covered on several pages: Marc MERLIN has written a LED-Matrix a bi color/RGB PWM driver for bi/tricolor matrices using only direct IO and/or shift registers. Code here: and video demo: More specific problems with the MAX7219 or MAX7221 have been discussed several times on the Arduino Hardware Forums. Playground - MAX72XXHardware.
Playground - Max7219. How to connect LED Matrix into Arduino using MAX 7219? - Electrical Engineering - Stack Exchange. Review – Maxim MAX7219 LED Display Driver IC. Use the Maxim MAX7219 LED display driver with Arduino in Chapter 56 of our Arduino Tutorials. The first chapter is here, the complete series is detailed here. Sooner or later Arduino enthusiasts and beginners alike will come across the MAX7219 IC.
And for good reason, it’s a simple and somewhat inexpensive method of controlling 64 LEDs in either matrix or numeric display form. Furthermore they can be chained together to control two or more units for even more LEDs. Overall – they’re a lot of fun and can also be quite useful, so let’s get started. Here’s an example of a MAX7219 and another IC which is a functional equivalent, the AS1107 from Austria Microsystems. At first glance you may think that it takes a lot of real estate, but it saves some as well.
You can even switch the display off for power saving mode, and still send it data while it is off. Before continuing, download and install the LedControl Arduino library as it is essential for using the MAX7219. Now for the sketch.