{"id":821,"date":"2017-02-17T17:05:59","date_gmt":"2017-02-17T17:05:59","guid":{"rendered":"http:\/\/dyor.roboticafacil.es\/?p=821"},"modified":"2018-04-06T05:35:34","modified_gmt":"2018-04-06T05:35:34","slug":"matriz-de-leds-8x8-max7219","status":"publish","type":"post","link":"https:\/\/dyor.webs.upv.es\/en\/matriz-de-leds-8x8-max7219\/","title":{"rendered":"8×8 LEDs Matrix (Max7219)"},"content":{"rendered":"

Learn how to use a 8×8 LEDs matrix (max7219). DYOR robot has a LEDs matrix to generate expressions (as a mouth). We describe it’s working principle and examples of use with de uso con Facilino<\/a> and Arduino.<\/p>\n

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How does a LEDs matrix work?<\/h3>\n

As in a mobile phone or computer screen composed by pixels, the 8×8 LEDs Matrix has upto 64 red LEDs which we can use to draw almost anything, actually, we have 18446744073709551616 combinations!<\/p>\n

The LEDs module communicates through SPI (Serial Programming Interface) with Arduino. It’s a communicaton protocol very common between microcontrolers and devices, with bidirectional communication which requires upto 4 lines (one for loading data, another one for the clock, one for data input and one for data output). However, given that the communication between Arduino and the LEDs module it’s unidirectional, we only require 3 lines: signals CS (Chip select), also known as LOAD, allows us to enable the device to receive information; signal DIN es the data input signal (to the module) and signal CLK is the clock signal.<\/p>\n

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Arduino Nano\u00a0 has SPI signals that can be used for this purpose:<\/p>\n