temperature display wifi bme280 and oled display

temperature display wifi bme280 and oled display.cpp

#include <LiquidCrystal_I2C.h>
#include <Wire.h>
#include <ESP8266WiFi.h>
#include <WiFiClient.h>
#include <ESP8266WebServer.h>
#include <ESP8266mDNS.h>
#include <limits>

#include <SPI.h>

#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#include <Adafruit_Sensor.h>
#include <Adafruit_BME280.h>

#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels

// Declaration for an SSD1306 display connected to I2C (SDA, SCL pins)
#define OLED_RESET     4 // Reset pin # (or -1 if sharing Arduino reset pin)
Adafruit_SSD1306 *display;

#ifndef STASSID
#define STASSID "PRISM"
#define STAPSK  "MazEgg8378"
#endif

const char* ssid = STASSID;
const char* password = STAPSK;

ESP8266WebServer server(80);

int D0 = 16;
int D1 = 5;
int D2 = 4;
int D3 = 0;
int D4 = 2;
int D5 = 14;
int D6 = 12;
int D7 = 13;
int D8 = 15;
int RX = 3;

LiquidCrystal_I2C *lcd;
float tempGraph[SCREEN_WIDTH] = {0};

static float lastTemperature = std::numeric_limits<float>::infinity();
Adafruit_BME280 *bme;

void setupDisplay() {
  display = new Adafruit_SSD1306(SCREEN_WIDTH, SCREEN_HEIGHT, &Wire, -1);

  // SSD1306_SWITCHCAPVCC = generate display voltage from 3.3V internally
  if (!display->begin(SSD1306_SWITCHCAPVCC, 0x3C)) { // Address 0x3D for 128x64
    Serial.println(F("SSD1306 allocation failed"));
    for (;;); // Don't proceed, loop forever
  }

  // Show initial display buffer contents on the screen --
  // the library initializes this with an Adafruit splash screen.
  display->clearDisplay();
  display->display();
  display->clearDisplay();
  delay(200); // Pause for 2 seconds

  // Clear the buffer
  display->clearDisplay();

  memset(tempGraph, 0, SCREEN_WIDTH * sizeof(float));
}

void setup() {
  Serial.begin(9600);
  Wire.begin(D2, D1);

  bme = new Adafruit_BME280();
  bool status = bme->begin(0x76, &Wire);
  //  bool status = bme->begin();

  setupDisplay();

  lcd = new LiquidCrystal_I2C(0x27, 16, 2);
  lcd->begin(16, 2);
  lcd->home();
  // Print a message to the lcd->
  lcd->setCursor(0, 1);
  lcd->print("Measuring temp!");
  lcd->backlight();

  WiFi.mode(WIFI_STA);
  WiFi.begin(ssid, password);

  lcd->setCursor(0, 0);

  if (status == false) {
    lcd->setCursor(0, 1);
    lcd->print("BME280 failed          ");
    Serial.print("SensorID was: 0x");
    Serial.println(bme->sensorID(), 16);
    while (1) {
      yield();
    }
  }

  lcd->setCursor(0, 0);

  lcd->print("connecting");

  // Wait for connection
  while (WiFi.status() != WL_CONNECTED) {
    lcd->print(".");
    delay(400);
  }

  lcd->setCursor(0, 0);
  String status1 = String("IP:" + WiFi.localIP().toString() + "     ");
  lcd->print(status1);

  if (MDNS.begin("esp8266")) {
    lcd->setCursor(0, 1);
    lcd->print("connected          ");
  } else {
    lcd->setCursor(0, 1);
    lcd->print("MDNS failed          ");
    delay(2000);
  }

  server.on("/", handleRoot);
  server.begin();
}

void displayGraph(float graph[SCREEN_WIDTH]) {

  //    display->drawLine(0, 0, display->width()-1, i, SSD1306_WHITE);
  //    display->display();
  int16_t i;

  // clear the bottom
  for (i = 0; i < SCREEN_WIDTH; i++) {
    float value = graph[i];

    int barHeight = (int)(((float)display->height() / 2) * value);
    display->drawLine(i, display->height(), i, display->height() -  barHeight, SSD1306_WHITE);
  }
}

void printBigText(String text) {
  display->clearDisplay();
  display->setTextColor(SSD1306_WHITE);        // Draw white text
  display->setCursor(10, 10);            // Start at top-left corner

  display->setTextSize(2);             // Draw 2X-scale text
  display->setTextColor(SSD1306_WHITE);
  display->print(text);

  displayGraph(tempGraph);
  display->display();
}

void handleRoot() {
  String tempString = String(lastTemperature, 3);
  String d = String("It's " + tempString + " C here!");

  if (lastTemperature == std::numeric_limits<float>::infinity()) {
    d = String("no measurements done yet");
  }

  //  digitalWrite(led, 1);
  server.send(200, "text/plain", d);
  //  digitalWrite(led, 0);
}


// the loop function runs over and over again forever
void loop() {
  static int loop = 0;
  //  digitalWrite(D4, HIGH);
  delay(50);
  //  digitalWrite(D4, LOW);
  delay(50);
  lcd->setCursor(0, 1);

  float temp = bme->readTemperature();

  if (isnan(temp) == false) {
    lastTemperature = temp;

    String tempString = String(temp, 3);
    String d = String(tempString + " 'C    ");

    lcd->print(d);
    printBigText(d);

    loop++;
    if (loop % 100 == 0) {
      pushNew(temp);
    }
  } else {
    lcd->print("temp fail! ");
    printBigText("temp fail! ");
  }
  server.handleClient();
  MDNS.update();
}

// buffer, push values in - and have access to the last 128 values
void pushNew(float temp) {
  // normalise between 0 and 40
  float normalised = temp / 40.0;

  memmove(tempGraph, tempGraph + 1, sizeof(tempGraph) - sizeof(float));
  tempGraph[SCREEN_WIDTH - 1] = normalised;
}