RGB 7 Segment Display Using Neo Pixel Led

RGB and addressable led, can be supplied with 3.3volts. Using these big panels we can make clock and other display devices.

TO display any Animations or Number on this 7 segment panel we need some components as follows:

1) NodeMcu or Arduino

2) Breadboard

3) 7 segment panels

4) USB and other connecting wires.

Hi guys, today we are going to discuss, interfacing of neo pixel led through Nodemcu (ESP8266-12E). Neo pixel is addressable led; we can program to display any number/name in any color using microcontroller. Neo pixel came in different smd packages, here we are using Ws2812b-5050 mini RGB.

This mini led has voltage ratings: 3.0v to 5.5volts @16mA (for each Led). Our Nodemcu has 3.3-volt regulator, to drive all the Led’s properly. Other details are given in the above image.

Here, I do all the power connections in parallel and all the Data connection in series. Using the 7-segment display method, and connect all the Led’s in proper format (As in diagram).

Each of the segment has 2 Led’s and One whole panel has 14 Led’s in total. We need 4 panels to display time (2 for Hours, 2 for minutes) for the future Clock project. Two more panels can be connected, to display seconds/any other values like Temperature.

Now, Turn Your schematics into PCB and arrange the Led’s in the format of general 7 segment display. Here you can get an example of this.

Making a beautiful looking PCB is equally important. So, I designed the PCB, started with a rectangular board outline then adding different type of board cut-out to PCB. Finally, this image may show my work to you.

Make connection of all the nets and tracks, build the copper area using GND connections for top and bottom layer. Connections can be done using Auto route/ EasyEDA is the best software for this type of work. And JLCPCB is the best PCB manufacturer for low cost and quality.

Always connect Data out of 1st led to Data in of 2nd led, Power connections are done in parallel. This led's can run on 3.3v without any resistor. So please keep in mind to add resistor on each led while working with high voltages.

Connect:

1) GND pin to Gnd of nodemcu

2) VCC pin to 3.3volts

3) Data IN pin to D4/ GPIO2

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Get BOM,CPL, Gerber and other important files through this link:

Download all the important files from here.

1) Counter:

Up-down counter is there in the code, We can change the counting 0 to 999 and delay between each count.

/disp_CountUP(500, 450);       // Count numbers in Ascending order  (NUMBER, DelayTime)
//  disp_CountDOWN(500, 250);     // Count numbers in Descending order (NUMBER, DelayTime)

Numbers displayed on each segment are of same color at a time. In the code color can be changed using the function.

RGB:

Red(brightness,0,0)

Green(0,brightness,0)

Blue(0,0,brightness)

Each pixel contains 2 led so animations can be drawn in this format, also the costom color can be obtained by making any two from RGB to High.

example:

Pink: RGB = (brightness,brightness,0)

This code is modified to display Animations and numbers on these 7 segment panels. Just Uncomment the portion of code, you want to use.

Example: To display numbers

//disp_Seg(200);                // Cycle through all segments        (DelayTime)
  disp_Digits(1000);            // Show digits from 0-9              (DelayTime)
  //disp_Animation();             // Show some Animations with the segments
 //disp_CountUP(500, 450);       // Count numbers in Ascending order  (NUMBER, DelayTime)
//  disp_CountDOWN(500, 250);     // Count numbers in Descending order (NUMBER, DelayTime)

Main test code for RGB neopixel... credit Electro point

#include <Adafruit_NeoPixel.h>


#define PIXELS_PER_SEGMENT  2     // Number of LEDs in each Segment
#define PIXELS_DIGITS       4     // Number of connected Digits 
#define PIXELS_PIN          2     // GPIO Pin


Adafruit_NeoPixel strip = Adafruit_NeoPixel(PIXELS_PER_SEGMENT * 7 * PIXELS_DIGITS, PIXELS_PIN, NEO_GRB + NEO_KHZ800);


//Pixel Arrangement
/*
          a
        f   b
          g
        e   c
          d
*/


// Segment array
byte segments[7] = {
  //abcdefg
  0b0000001,     // Segment g
  0b0000100,     // Segment e
  0b0001000,     // Segment d
  0b0010000,     // Segment c
  0b0100000,     // Segment b
  0b1000000,     // Segment a
  0b0000010     // Segment f
};


//Digits array
byte digits[10] = {
  //abcdefg
  0b1111110,     // 0
  0b0110000,     // 1
  0b1101101,     // 2
  0b1111001,     // 3
  0b0110011,     // 4
  0b1011011,     // 5
  0b1011111,     // 6
  0b1110000,     // 7
  0b1111111,     // 8
  0b1110011      // 9
};


//Clear all the Pixels
void clearDisplay() {
  for (int i = 0; i < strip.numPixels(); i++) {
    strip.setPixelColor(i, strip.Color(0, 0, 0));
  }
  strip.show();
}


void setup() {
  strip.begin();
}


void loop() {
  //disp_Seg(200);                // Cycle through all segments        (DelayTime)
  disp_Digits(1000);            // Show digits from 0-9              (DelayTime)
  //disp_Animation();             // Show some Animations with the segments
 //disp_CountUP(500, 450);       // Count numbers in Ascending order  (NUMBER, DelayTime)
//  disp_CountDOWN(500, 250);     // Count numbers in Descending order (NUMBER, DelayTime)
}


void disp_Seg(int wait) {
  clearDisplay();
  for (int d = 0; d < 5; d++) {
    for (int i = 6; i > 0; i--) {
      for (int n = 0; n < PIXELS_DIGITS; n++) {
        writeSegment(n, i);
      }
      strip.show();
      delay(wait);
    }
  }
}


void disp_Digits(int wait) {
  clearDisplay();
  for (int i = 0; i < 10; i++) {
    for (int n = 0; n < PIXELS_DIGITS; n++) {
      writeDigit(n, i);
    }
    strip.show();
    delay(wait);
  }
}


void disp_CountUP(int num, int wait) {
  clearDisplay();
  for (int i = 0; i <= num; i++) {
    writeDigit(0, (i / 100) % 10);
    writeDigit(1, (i / 10) % 10);
    writeDigit(2, (i / 1) % 10);
    strip.show();
    delay(wait);
  }
}


void disp_CountDOWN(int num, int wait) {
  clearDisplay();
  for (int i = num; i >= 0; i--) {
    writeDigit(0, (i / 100) % 10);
    writeDigit(1, (i / 10) % 10);
    writeDigit(2, (i / 1) % 10);
    strip.show();
    delay(wait);
  }
}


void disp_Animation() {
  clearDisplay();
  //UP-DOWN
  for (int i = 0; i < 7; i++) {
    for (int n = 0; n < PIXELS_DIGITS; n++) writeSegment(n, 5);
    strip.show();
    delay(100);
    for (int n = 0; n < PIXELS_DIGITS; n++) writeSegment(n, 0);
    strip.show();
    delay(100);
    for (int n = 0; n < PIXELS_DIGITS; n++) writeSegment(n, 2);
    strip.show();
    delay(100);
    for (int n = 0; n < PIXELS_DIGITS; n++) writeSegment(n, 0);
    strip.show();
    delay(100);
    for (int n = 0; n < PIXELS_DIGITS; n++) writeSegment(n, 5);
    strip.show();
    delay(100);
  }
  //LEFT-RIGHT
  for (int i = 0; i < 5; i++) {
    for (int n = 0; n < PIXELS_DIGITS; n++) {
      writeSegment(n, 6);
      strip.show();
      delay(150);
    }
    for (int n = PIXELS_DIGITS - 1; n >= 0; n--) {
      writeSegment(n, 3);
      strip.show();
      delay(150);
    }
    clearDisplay();
    for (int n = 0; n < PIXELS_DIGITS; n++) {
      writeSegment(n, 1);
      strip.show();
      delay(150);
    }
    for (int n = PIXELS_DIGITS - 1; n >= 0; n--) {
      writeSegment(n, 4);
      strip.show();
      delay(150);
    }
    clearDisplay();
  }
  //ZIG-ZAG
  for (int i = 0; i < 5; i++) {
    for (int n = 0; n < PIXELS_DIGITS; n++) {
      writeSegment(n, 6);
      strip.show();
      delay(125);
      clearDisplay();
      writeSegment(n, 1);
      strip.show();
      delay(125);
      clearDisplay();
      writeSegment(n, 4);
      strip.show();
      delay(125);
      clearDisplay();
      writeSegment(n, 3);
      strip.show();
      delay(125);
      clearDisplay();
    }
  }
}


void writeDigit(int index, int val) {
  byte digit = digits[val];
  for (int i = 6; i >= 0; i--) {
    int offset = index * (PIXELS_PER_SEGMENT * 7) + i * PIXELS_PER_SEGMENT;
    uint32_t color;
    if (digit & 0x01 != 0) {
      if (val == 1) color = strip.Color(50, 0,  0);
      if (val == 2) color = strip.Color(50, 50, 0);
      if (val == 3) color = strip.Color(50, 0, 50);
      if (val == 4) color = strip.Color(0, 50,  0);
      if (val == 5) color = strip.Color(0, 50, 50);
      if (val == 6) color = strip.Color(0,  0, 50);
      if (val == 7) color = strip.Color(50, 25, 0);
      if (val == 8) color = strip.Color(25, 5, 75);
      if (val == 9) color = strip.Color(75, 25, 5);
      if (val == 0) color = strip.Color(5, 75, 25);
    }
    else
      color = strip.Color(0, 0, 0);


    for (int j = offset; j < offset + PIXELS_PER_SEGMENT; j++) {
      strip.setPixelColor(j, color);
    }
    digit = digit >> 1;
  }
}


void writeSegment(int index, int val) {
  byte seg = segments[val];
  for (int i = 6; i >= 0; i--) {
    int offset = index * (PIXELS_PER_SEGMENT * 7) + i * PIXELS_PER_SEGMENT;
    uint32_t color;
    if (seg & 0x01 != 0) {
      if (val == 0) color = strip.Color(50, 0, 0);
      if (val == 1) color = strip.Color(0, 50, 50);
      if (val == 2) color = strip.Color(0, 50, 0);
      if (val == 3) color = strip.Color(50, 0, 50);
      if (val == 4) color = strip.Color(50, 50, 50);
      if (val == 5) color = strip.Color(0, 0, 50);
      if (val == 6) color = strip.Color(50, 50, 0);
    }
    else
      color = strip.Color(0, 0, 0);


    for (int j = offset; j < offset + PIXELS_PER_SEGMENT; j++) {
      strip.setPixelColor(j, color);
    }
    seg = seg >> 1;
  }
}

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