SSD1306Wire  display(0x3c, 4, 15);

//add
  pinMode(16, OUTPUT);
  digitalWrite(16, 1);
// before
  display.init();

 /**
  * The MIT License (MIT)
  *
  * Copyright (c) 2018 by ThingPulse, Daniel Eichhorn
  * Copyright (c) 2018 by Fabrice Weinberg
  *
  * Permission is hereby granted, free of charge, to any person obtaining a copy
  * of this software and associated documentation files (the "Software"), to deal
  * in the Software without restriction, including without limitation the rights
  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  * copies of the Software, and to permit persons to whom the Software is
  * furnished to do so, subject to the following conditions:
  *
  * The above copyright notice and this permission notice shall be included in all
  * copies or substantial portions of the Software.
  *
  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  * SOFTWARE.
  *
  * ThingPulse invests considerable time and money to develop these open source libraries.
  * Please support us by buying our products (and not the clones) from
  * https://thingpulse.com
  *
  */

  #include <Wire.h>  // Only needed for Arduino 1.6.5 and earlier
  #include "SSD1306Wire.h" // legacy include: `#include "SSD1306.h"`
  SSD1306Wire  display(0x3c, 4, 15);

// Adapted from Adafruit_SSD1306
void drawLines() {
  for (int16_t i=0; i<display.getWidth(); i+=4) {
    display.drawLine(0, 0, i, display.getHeight()-1);
    display.display();
    delay(10);
  }
  for (int16_t i=0; i<display.getHeight(); i+=4) {
    display.drawLine(0, 0, display.getWidth()-1, i);
    display.display();
    delay(10);
  }
  delay(250);

  display.clear();
  for (int16_t i=0; i<display.getWidth(); i+=4) {
    display.drawLine(0, display.getHeight()-1, i, 0);
    display.display();
    delay(10);
  }
  for (int16_t i=display.getHeight()-1; i>=0; i-=4) {
    display.drawLine(0, display.getHeight()-1, display.getWidth()-1, i);
    display.display();
    delay(10);
  }
  delay(250);

  display.clear();
  for (int16_t i=display.getWidth()-1; i>=0; i-=4) {
    display.drawLine(display.getWidth()-1, display.getHeight()-1, i, 0);
    display.display();
    delay(10);
  }
  for (int16_t i=display.getHeight()-1; i>=0; i-=4) {
    display.drawLine(display.getWidth()-1, display.getHeight()-1, 0, i);
    display.display();
    delay(10);
  }
  delay(250);
  display.clear();
  for (int16_t i=0; i<display.getHeight(); i+=4) {
    display.drawLine(display.getWidth()-1, 0, 0, i);
    display.display();
    delay(10);
  }
  for (int16_t i=0; i<display.getWidth(); i+=4) {
    display.drawLine(display.getWidth()-1, 0, i, display.getHeight()-1);
    display.display();
    delay(10);
  }
  delay(250);
}

// Adapted from Adafruit_SSD1306
void drawRect(void) {
  for (int16_t i=0; i<display.getHeight()/2; i+=2) {
    display.drawRect(i, i, display.getWidth()-2*i, display.getHeight()-2*i);
    display.display();
    delay(10);
  }
}

// Adapted from Adafruit_SSD1306
void fillRect(void) {
  uint8_t color = 1;
  for (int16_t i=0; i<display.getHeight()/2; i+=3) {
    display.setColor((color % 2 == 0) ? BLACK : WHITE); // alternate colors
    display.fillRect(i, i, display.getWidth() - i*2, display.getHeight() - i*2);
    display.display();
    delay(10);
    color++;
  }
  // Reset back to WHITE
  display.setColor(WHITE);
}

// Adapted from Adafruit_SSD1306
void drawCircle(void) {
  for (int16_t i=0; i<display.getHeight(); i+=2) {
    display.drawCircle(display.getWidth()/2, display.getHeight()/2, i);
    display.display();
    delay(10);
  }
  delay(1000);
  display.clear();

  // This will draw the part of the circel in quadrant 1
  // Quadrants are numberd like this:
  //   0010 | 0001
  //  ------|-----
  //   0100 | 1000
  //
  display.drawCircleQuads(display.getWidth()/2, display.getHeight()/2, display.getHeight()/4, 0b00000001);
  display.display();
  delay(200);
  display.drawCircleQuads(display.getWidth()/2, display.getHeight()/2, display.getHeight()/4, 0b00000011);
  display.display();
  delay(200);
  display.drawCircleQuads(display.getWidth()/2, display.getHeight()/2, display.getHeight()/4, 0b00000111);
  display.display();
  delay(200);
  display.drawCircleQuads(display.getWidth()/2, display.getHeight()/2, display.getHeight()/4, 0b00001111);
  display.display();
}

void printBuffer(void) {
  // Initialize the log buffer
  // allocate memory to store 8 lines of text and 30 chars per line.
  display.setLogBuffer(5, 30);

  // Some test data
  const char* test[] = {
      "Hello",
      "World" ,
      "----",
      "Show off",
      "how",
      "the log buffer",
      "is",
      "working.",
      "Even",
      "scrolling is",
      "working"
  };

  for (uint8_t i = 0; i < 11; i++) {
    display.clear();
    // Print to the screen
    display.println(test[i]);
    // Draw it to the internal screen buffer
    display.drawLogBuffer(0, 0);
    // Display it on the screen
    display.display();
    delay(500);
  }
}

void setup() {
  pinMode(16, OUTPUT);
  digitalWrite(16, 1);

  display.init();

  // display.flipScreenVertically();

  display.setContrast(255);

  drawLines();
  delay(1000);
  display.clear();

  drawRect();
  delay(1000);
  display.clear();

  fillRect();
  delay(1000);
  display.clear();

  drawCircle();
  delay(1000);
  display.clear();

  printBuffer();
  delay(1000);
  display.clear();
}

void loop() { }