The board ships with a demo that tests out the buttons, LEDs, EPD, accelerometer, and speaker. It may be handy if you ever need to verify your hardware is fully working!

  • The NeoPixels will light up in a rainbow design
  • When button A, B, C are pressed, the LEDs will turn to a solid color red, green or blue
  • When button D is pressed, a chime sounds
  • Red LED blinks on and off
  • Display shows bitmap MagTag logo. When the accelerometer detects that the board is 'upside down' the display is rotated
  • In serial console, light sensor reading and accelerometer XYZ is output
  • In serial console, I2C port on STEMMA QT is scanned and visible I2C device addresses are printed

You can put your board into UF2 Bootloader mode and drag-n-drop this file on to load it:

You can download the full example code for compilation by clicking Download Project Zip on this sketch to get all the files (there are two header files, coin.h with 8-bit audio and magtaglogo.h with the bitmap logo)

Before uploading to your magtag make sure you downloaded the full project and got the two header files!

If you are looking for the ThinkInk library to use with this example, click the link below to get a zip including the ThinkInk library.

To get the full set of libraries that go with the Adafruit EPD library, click this link and download the latest zip file.

// SPDX-FileCopyrightText: 2020 Limor Fried for Adafruit Industries
//
// SPDX-License-Identifier: MIT

#include <Adafruit_NeoPixel.h>
#include <Wire.h>
#include <Adafruit_ThinkInk.h>
#include <Adafruit_LIS3DH.h>
#include "coin.h"
#include "magtaglogo.h"

Adafruit_NeoPixel intneo = Adafruit_NeoPixel(4, PIN_NEOPIXEL, NEO_GRB + NEO_KHZ800);
ThinkInk_290_Grayscale4_T5 display(EPD_DC, EPD_RESET, EPD_CS, -1, -1);
Adafruit_LIS3DH lis = Adafruit_LIS3DH();

uint8_t j = 0;
void setup() {
  Serial.begin(115200);
  //while (!Serial) { delay(10); }
  delay(100);
  Serial.println("Adafruit EPD Portal demo");

  intneo.begin();
  intneo.setBrightness(50);
  intneo.show(); // Initialize all pixels to 'off'

  pinMode(BUTTON_A, INPUT_PULLUP);
  pinMode(BUTTON_B, INPUT_PULLUP);
  pinMode(BUTTON_C, INPUT_PULLUP);
  pinMode(BUTTON_D, INPUT_PULLUP);

  pinMode(SPEAKER_SHUTDOWN, OUTPUT);
  digitalWrite(SPEAKER_SHUTDOWN, LOW);

  // Red LED
  pinMode(13, OUTPUT);

  // Neopixel power
  pinMode(NEOPIXEL_POWER, OUTPUT);
  digitalWrite(NEOPIXEL_POWER, LOW); // on

  display.begin(THINKINK_MONO);

  if (! lis.begin(0x19)) {
    Serial.println("Couldnt start LIS3DH");
    display.clearBuffer();
    display.setTextSize(3);
    display.setTextColor(EPD_BLACK);
    display.setCursor(20, 40);
    display.print("No LIS3DH?");
    display.display();
    while (1) delay(100);
  }

  analogReadResolution(12); //12 bits
  analogSetAttenuation(ADC_11db);  //For all pins
  display.clearBuffer();
  display.drawBitmap(0, 38, magtaglogo_mono, MAGTAGLOGO_WIDTH, MAGTAGLOGO_HEIGHT, EPD_BLACK);
  display.display();
}



uint8_t rotation = 0;

void loop() {
  j++;
  if (j == 0) {
    Serial.print("Rotation: "); Serial.println(rotation);
    if (rotation == 0 || rotation == 2) {
      display.setRotation(rotation);
      display.clearBuffer();
      display.drawBitmap(0, 38, magtaglogo_mono, MAGTAGLOGO_WIDTH, MAGTAGLOGO_HEIGHT, EPD_BLACK);
      display.display();
    }
  }
  // Red LED On
  digitalWrite(13, HIGH);

  //Serial.print(".");
  if (j % 10 == 0) {
      sensors_event_t event;
      lis.getEvent(&event);

      /* Display the results (acceleration is measured in m/s^2) */
      Serial.print("X: "); Serial.print(event.acceleration.x);
      Serial.print(" \tY: "); Serial.print(event.acceleration.y);
      Serial.print(" \tZ: "); Serial.print(event.acceleration.z);
      Serial.println(" m/s^2 ");
      if ((event.acceleration.x < -5) && (abs(event.acceleration.y) < 5)) {
        rotation = 1;
      }
      if ((abs(event.acceleration.x) < 5) && (event.acceleration.y > 5)) {
        rotation = 0;
      }
      if ((event.acceleration.x > 5) && (abs(event.acceleration.y) < 5)) {
        rotation = 3;
      }
      if ((abs(event.acceleration.x) < 5) && (event.acceleration.y < -5)) {
        rotation = 2;
      }

      int light = analogRead(LIGHT_SENSOR);
      Serial.print("Light sensor: ");
      Serial.println(light);

      Serial.print("I2C scanner: ");
      for (int i = 0x07; i <= 0x77; i++) {
        Wire.beginTransmission(i);
        bool found (Wire.endTransmission() == 0);
        if (found) {
          Serial.printf("0x%02x, ", i);
        }
      }
      Serial.println();
  }

  if (! digitalRead(BUTTON_A)) {
    Serial.println("Button A pressed");
    intneo.fill(0xFF0000);
    intneo.show();
  }
  else if (! digitalRead(BUTTON_B)) {
    Serial.println("Button B pressed");
    intneo.fill(0x00FF00);
    intneo.show();
  }
  else if (! digitalRead(BUTTON_C)) {
    Serial.println("Button C pressed");
    intneo.fill(0x0000FF);
    intneo.show();
  }
  else if (! digitalRead(BUTTON_D)) {
    intneo.fill(0x0);
    intneo.show();
    Serial.println("Button D pressed");
    digitalWrite(SPEAKER_SHUTDOWN, HIGH);
    play_tune(audio, sizeof(audio));
    digitalWrite(SPEAKER_SHUTDOWN, LOW);
  } else {
    // neopixelate
    for (int i = 0; i < intneo.numPixels(); i++) {
      intneo.setPixelColor(i, Wheel(((i * 256 / intneo.numPixels()) + j) & 255));
    }
    intneo.show();
  }

  // Red LED off
  digitalWrite(13, LOW);


  delay(10);
}

void play_tune(const uint8_t *audio, uint32_t audio_length) {
  uint32_t t;
  uint32_t prior, usec = 1000000L / SAMPLE_RATE;

  prior = micros();
  for (uint32_t i=0; i<audio_length; i++) {
    while((t = micros()) - prior < usec);
    dacWrite(A0, audio[i]);
    prior = t;
  }
}

// Input a value 0 to 255 to get a color value.
// The colours are a transition r - g - b - back to r.
uint32_t Wheel(byte WheelPos) {
  WheelPos = 255 - WheelPos;
  if (WheelPos < 85) {
    return intneo.Color(255 - WheelPos * 3, 0, WheelPos * 3);
  }
  if (WheelPos < 170) {
    WheelPos -= 85;
    return intneo.Color(0, WheelPos * 3, 255 - WheelPos * 3);
  }
  WheelPos -= 170;
  return intneo.Color(WheelPos * 3, 255 - WheelPos * 3, 0);
}

This guide was first published on Nov 10, 2020. It was last updated on Mar 29, 2024.

This page (Shipping Demo) was last updated on Mar 29, 2024.

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