obniz Parts Library

7SegmentLED_MAX7219

GitHub
7SegmentLED_MAX7219
Usable Devices :
obniz_board
Found at :
www.adafruit.com a.co

7SegmentLED_MAX7219

This class controls 7 segment LEDs connected to MAX7219.
One MAX7219 can drive up to 8 digits.
And chaining connections of MAX7219 is available.

wired(obniz, { clk, cs, din, gnd, vcc});

  1. clk: Clock of SPI. connect to CLK of MAX7219
  2. cs: Chip selection. connect to LOAD(CK) of MAX7219
  3. din: MOSI of SPI. connect to DIN of MAX7219
  4. gnd: GND
  5. vcc: Power supply +5V

This is a example.

For example, 7segments are
LED

If you want to chain connection, connect DIN of next to DOUT of before.

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219", { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4); // one MAX7219 which has 4 digits
segment.setNumber(0,0,5,false); // show '5' on first digit. without dot.

init(numberOfDisplays, digits)

Initialize LEDs.
numberOfDisplays is number of MAX7219.
digits is number of digits each MAX7219 has.
So, If 4 digits per MAX7219 and only one MAX7219 then init(1,4)

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);  // one MAX7219 which has 4 digits

brightness(display,value)

Change brightness on specific digit.
value must be within 0 to 15.

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.brightness(0, 1)
segment.setNumber(0, 0, 5, false);

brightnessAll(value)

Change all LED brightness.

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.brightnessAll(1)
segment.setNumber(0, 0, 5, false);

setNumber(display,digit,number,dp)

change the digit of LED showing.

  1. display: index of MAX7219.
  2. digit: digit in specified MAX7219.
  3. number: the number want to show
  4. dp: dot to show.

value accept

Value description
0 to 9 number
'on' all on (=8)
'off' all off
'-' show "-"
'e' show "E"
'h' show "H"
'l' show "L"
'p' show "P"
// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.setNumber(0,0,5,false);
segment.setNumber(0,1,"e",false);
segment.setNumber(0,2,"off",true);

clear(display)

Clear specified MAX7219 connected LEDs

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.setNumber(0, 0, 5, false);
segment.setNumber(0,1,"e",false);
segment.clear(0)

clearAll()

Clear all LEDs.

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.setNumber(0, 0, 5, false);
segment.clearall();

test()

Send test command to MAX7219.

// Javascript Example
const segment = obniz.wired("7SegmentLED_MAX7219",  { clk:0, cs:1, din:2, gnd:3, vcc:4});
segment.init(1, 4);
segment.test();

Supported from: obniz.js 3.5.0