BME680 & Waveshare 2.9 - I2C & SPI

// Arduino BME680 & Waveshare 2.9 e-paper - SPI and I2C

//#include <SPI.h>
#include <Wire.h>
#include <GxEPD2_BW.h>
#include <Fonts/FreeMonoBold9pt7b.h>
#include <Adafruit_Sensor.h>
#include "Adafruit_BME680.h"



// SPI pin mapping (ESP-WROOM-32)
//#define SCK   18
//#define MISO  19
//#define MOSI  23
#define BME_CS    0
#define DISP_CS   5
#define DISP_DC   17
#define DISP_RST  16
#define DISP_BUSY 4

#define SEALEVELPRESSURE_HPA (1013.25)

// Display driver
GxEPD2_BW<GxEPD2_290_T94_V2, GxEPD2_290_T94_V2::HEIGHT> display(
  GxEPD2_290_T94_V2(DISP_CS, DISP_DC, DISP_RST, DISP_BUSY)
);


Adafruit_BME680 bme; // I2C
//Adafruit_BME680 bme(BME_CS, MOSI, MISO, SCK); // Software SPI

bool sensor_error = false, status;
float temperature, humidity, pressure, gas, alt;


void selectSensor() {
  digitalWrite(DISP_CS, HIGH);
  digitalWrite(BME_CS, LOW);
  sensor_error = false;
}

void selectDisplay() {
  digitalWrite(BME_CS, HIGH);
  digitalWrite(DISP_CS, LOW);
}

// Read BME data
void readValues() {
  selectSensor();
  if (!bme.performReading()) {
    sensor_error = true;
    Serial.println("Error reading from sensor!");
    return;
  }
  delay(400);
  temperature = bme.temperature;
  humidity    = bme.humidity;
  pressure    = bme.pressure;
  alt         = bme.readAltitude(SEALEVELPRESSURE_HPA);

  Serial.print("Sensor values: ");
  Serial.print(temperature); Serial.print(" °C, ");
  Serial.print(humidity);    Serial.print(" %, ");
  Serial.print(pressure);    Serial.println(" Pa");
}

// Update display
void displayValues(int16_t x, int16_t y, int16_t sep) {
  //if (sensor_error) return; -- disabled for debugging
  selectDisplay();
  if (!sensor_error) {
    display.setRotation(1);
    display.setFont(&FreeMonoBold9pt7b);
    display.setTextColor(GxEPD_BLACK);
    display.setFullWindow();
    display.firstPage();
    do {
      display.fillScreen(GxEPD_WHITE);
      display.setCursor(x, y);
      display.print("T: ");  display.print(temperature, 1); display.println(" °C");
      display.setCursor(x, y + sep);
      display.print("H: ");  display.print(humidity, 1);    display.println(" %");
      display.setCursor(x, y + sep*2);
      display.print("P: ");  display.print(pressure / 100.0, 1); display.println(" hPa");
      display.setCursor(x, y + sep*3);
      display.print("Alt: "); display.print(alt, 1);        display.println(" m");
      display.setCursor(x, y + sep*4);
    } while (display.nextPage());

    Serial.println("Display updated."); }
  else {
    display.setRotation(1);
    display.setFont(&FreeMonoBold9pt7b);
    display.setTextColor(GxEPD_BLACK);
    display.setFullWindow();
    display.firstPage();
    do {
      display.fillScreen(GxEPD_WHITE);
      display.setCursor(x, y);
      display.print("Communication error!");
    } while (display.nextPage());
  }
}


// Setup
void setup() {
  Serial.begin(115200);
  delay(100);

  // Start SPI manually
  SPI.begin();


  // Configure CS pins
  pinMode(BME_CS, OUTPUT);
  pinMode(DISP_CS, OUTPUT);
  digitalWrite(BME_CS, HIGH);
  digitalWrite(DISP_CS, HIGH);

  // Initialize display
  selectDisplay();
  display.init(115200, true, 2, false);

  // Clear display once
  display.setRotation(1);
  display.setFullWindow();
  display.firstPage();
  do {
    display.fillScreen(GxEPD_WHITE);
  } while (display.nextPage());

  // Initialize sensor
  selectSensor();
  status = bme.begin();
  if (!status) {
    Serial.println("BME680 not found!");
  }

  bme.setTemperatureOversampling(BME680_OS_4X);
  bme.setHumidityOversampling(BME680_OS_2X);
  bme.setPressureOversampling(BME680_OS_4X);
  bme.setIIRFilterSize(BME680_FILTER_SIZE_3);

  Serial.println("Setup complete.");
  delay(2000);
}

void loop() {
  Serial.println("\nNew cycle...");
  readValues();
  displayValues(20, 20, 20);
  Serial.println("Waiting 15 seconds...\n");
  delay(15000);
}