obniz/parts/Display/7SegmentLED_MAX7219/index.js

obniz sdk for javascript

class _7SegmentLED_MAX7219 {
  constructor() {
    this.keys = ['vcc', 'gnd', 'din', 'cs', 'clk'];
    this.requiredKeys = ['din', 'cs', 'clk'];
  }

  static info() {
    return {
      name: '7SegmentLED_MAX7219',
    };
  }

  wired(obniz) {
    this.cs = obniz.getIO(this.params.cs);
    // logich high must 3.5v <=
    if (obniz.isValidIO(this.params.vcc)) {
      obniz.getIO(this.params.vcc).output(true);
    }
    if (obniz.isValidIO(this.params.gnd)) {
      obniz.getIO(this.params.gnd).output(false);
    }

    // max 10Mhz but motor driver can't
    this.params.frequency = this.params.frequency || 10 * 1000 * 1000;
    this.params.mode = 'master';
    this.params.mosi = this.params.din;
    this.params.drive = '3v';
    this.spi = this.obniz.getSpiWithConfig(this.params);

    // reset a onece
    this.cs.output(true);
    this.cs.output(false);
    this.cs.output(true);
  }

  init(numOfDisplay, digits) {
    this.numOfDisp = numOfDisplay;
    this.digits = digits;
    this.writeAllDisp([0x09, 0xff]); // Code B decode for digits 7-0
    this.writeAllDisp([0x0a, 0x05]); // brightness 11/32 0 to f
    this.writeAllDisp([0x0b, digits - 1]);
    this.writeAllDisp([0x0c, 0x01]); // Shutdown to normal operation
    this.writeAllDisp([0x0f, 0x00]);
    this.obniz.wait(10);
  }

  clear(disp) {
    for (let i = 0; i < this.digits; i++) {
      this.writeOneDisp(disp, [i + 1, 0x0f]);
    }
  }

  clearAll() {
    for (let i = 0; i < this.numOfDisp; i++) {
      for (let j = 0; j < this.digits; j++) {
        this.writeAllDisp([j + 1, 0x0f]);
      }
    }
  }

  test() {
    this.writeAllDisp([0x0f, 0x00]); // test command
  }

  brightness(disp, val) {
    this.writeOneDisp(disp, [0x0a, val]); // 0 to 15;
  }

  brightnessAll(val) {
    this.writeAllDisp([0x0a, val]); // 0 to 15;
  }

  writeAllDisp(data) {
    for (let i = 0; i < this.numOfDisp; i++) {
      this.writeOneDisp(i, data);
    }
  }

  writeOneDisp(disp, data) {
    this.cs.output(false);
    for (let i = 0; i < disp; i++) {
      this.spi.write([0x00, 0x00]);
    }
    this.spi.write(data);
    for (let i = 0; i < this.numOfDisp - (disp + 1); i++) {
      this.spi.write([0x00, 0x00]);
    }
    this.cs.output(true);
  }

  setNumber(disp, digit, number, dp) {
    if (digit >= 0 && digit <= this.digits - 1) {
      this.writeOneDisp(disp, [digit + 1, this.encodeBCD(number, dp)]);
    }
  }

  encodeBCD(decimal, dp) {
    let dpreg;
    if (dp == true) {
      dpreg = 0x80;
    } else {
      dpreg = 0x00;
    }
    if (decimal >= 0 && decimal <= 9) {
      return decimal | dpreg;
    } else if (decimal == '-' || decimal == 10) {
      return 0x0a | dpreg;
    } else if (decimal == 'e' || decimal == 11) {
      return 0x0b | dpreg;
    } else if (decimal == 'h' || decimal == 12) {
      return 0x0c | dpreg;
    } else if (decimal == 'l' || decimal == 13) {
      return 0x0d | dpreg;
    } else if (decimal == 'p' || decimal == 14) {
      return 0x0e | dpreg;
    } else if (decimal == 'on') {
      // light all segments
      return 0x88;
    } else if (decimal == 'off') {
      return 0x0f | dpreg;
    } else {
      return 0x0f | dpreg;
    }
  }
}

if (typeof module === 'object') {
  module.exports = _7SegmentLED_MAX7219;
}