Led.Matrix

The Led.Matrix class constructs an object that may represent one or more (chained) LED Matrix (MAX7219CNG) devices attached to the physical board.

Known supported devices:

See all on Tindie!

• MAX7219 Dot Matrix MCU LED Display Control Module Kit For Arduino With Dupont Cable
• LED Matrix Kit
• DIY MAX7219 Red LED Dot Matrix Display Module for Arduino
• Dot Matrix Display Kit w/MAX7219 IC, PCB
• Dot Matrix Chain Display Kit Max7219 V2

Adafruit offers a selection of colors 8x8 matrices:

• White
• Amber
• Yellow
• Green
• Blue

(This list only represents devices that I've personally confirmed, please add devices as needed.)

Parameters

• options An object of property parameters.

Property Name	Type	Value(s)	Properties	Required
pins	Object	A valid pins object or pins array	`data`, `clock`, `cs`	yes
devices	Number	1-n	For single device cases, this can be omitted. Defaults to `1`.	no

```js var matrix = new five.Led.Matrix({ pins: { data: 2, clock: 3, cs: 4 } });

### Shape

```js
{ 
  isMatrix: ...Boolean true|false (from LedControl). READONLY
  devices: ...Number of devices controlled. READONLY
}

Usage

var five = require("johnny-five");
var board = new five.Board();

board.on("ready", function() {

  var matrix = new five.Led.Matrix({
    pins: {
      data: 2,
      clock: 3,
      cs: 4
    }, 
    devices: 1
  });

  matrix.on();

  this.repl.inject({
    display: matrix.device(0)
  });
});

API

NOTE: When the device is turned off (with the off method), data is retained and will be displayed on the device when turned on (with the on method). This is useful when powering the devices from a battery, by providing a power saving mechanism.

• on() Turn on all matrix devices.
• on(index) Turn on matrix device at specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Turn on a specific device by index.
matrix.on(0);

// Turn on all devices
matrix.on();

• off() Turn off all matrix devices.
• off(index) Turn off matrix device at specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Turn off a specific device by index.
matrix.off(0);

// Turn off all devices
matrix.off();

// Send data to the the matrix
// ...Turn on the device to see the data displayed

• clear() Shut off all LEDs, for all devices.
• clear(index) Shut off all LEDs, for a device at specified index.

Note: clear() does not shut off the device.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Clear the entire display of a specified device.
matrix.clear(0);

// Clear the entire display for all devices
matrix.clear();

• brightness(0-100) Set the brightness from 0-100%, of all devices.
• brightness(index, 0-100) Set the brightness from 0-100%, for a device at specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Set the brightness of a specified device.
matrix.brightness(0, 100);

// Set the brightness for all devices
matrix.brightness(100);

• led(row, col, 1|0) Set on/off state for led at row and col (0-8, 0-8), of all devices.
• led(index, row, col, state) Set on/off state for led at row and col (00-8), for a device at the specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Turn on the top-left led of the specified device
matrix.led(0, 0, 0, 1);

// Turn on the top-left led of all devices
matrix.led(0, 0, 1);

• row(row, 0-255) Set row (0-8) value to 8-bit byte (0-255), of all devices.
• row(index, row, 0-255) Set row (0-8) value to 8-bit byte (0-255), for a device at the specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Turn on the entire first row of the specified device
matrix.row(0, 0, 255);

// Turn on the entire first row of all devices
matrix.row(0, 255);

• column(column, 0-255) Set column (0-8) value to 8-bit byte (0-255), of all devices.
• column(index, column, 0-255) Set column (0-8) value to 8-bit byte (0-255), for a device at the specified index.

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

// Turn on the entire first column of the specified device
matrix.column(0, 0, 255);

// Turn on the entire first column of all devices
matrix.column(0, 255);

• draw(character) Draw a "character" to all devices.
• draw(index, character) Draw a "character" to a device at the specified index.

Valid "character" values:

• A single character string, eg. "A", "b", "1", "$"
• An 8 element array of 8-bit values, eg. [0x00, 0x04, 0x15, 0x0E, 0x15, 0x04, 0x00, 0x00] (That array represents * character).
• An 8 element array of 8-bit binary string values, eg.

[
  "01100110",
  "10011001",
  "10000001",
  "10000001",
  "01000010",
  "00100100",
  "00011000",
  "00000000"
];

var matrix = new five.Led.Matrix({
  pins: {
    data: 2,
    clock: 3,
    cs: 4
  }
});

var heart = [
  "01100110",
  "10011001",
  "10000001",
  "10000001",
  "01000010",
  "00100100",
  "00011000",
  "00000000"
];

// Draw a heart to the specified device
matrix.draw(0, heart);

// Draw a heart to all devices
matrix.draw(heart);

var exclamation = [
  0x04, 
  0x04, 
  0x04, 
  0x04, 
  0x00, 
  0x00, 
  0x04, 
  0x00
];

// Draw an exclamation to the specified device
matrix.draw(0, exclamation);

// Draw an exclamation to all devices
matrix.draw(exclamation);

var asterisk = "*";

// Draw an asterisk to the specified device
matrix.draw(0, asterisk);

// Draw an asterisk to all devices
matrix.draw(asterisk);

Events

Led.Matrix objects are output only and therefore do not emit any events.