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--- iothings:laboratoare:2022:lab7 [2023/11/20 21:28]
dan.tudose [Project Overview]
+++ iothings:laboratoare:2022:lab7 [2023/11/20 22:15] (current)
dan.tudose [Web BLE Application]
@@ Line 94: / Line 94: @@
   * humidity: **0x246F**
+==== Mobile App ====
+{{ :iothings:laboratoare:2022:nrf_connect.png?150|}}
+To verify the proper creation of the BLE Server and to receive notifications for temperature, humidity, and pressure, we'll utilize a smartphone application.
+Most contemporary smartphones come equipped with BLE capabilities. You can check your smartphone's specifications to confirm its BLE compatibility.
+Note: The smartphone can function as either a client or a server. In this context, it will act as the client, establishing a connection with the Sparrow BLE server.
+For our testing purposes, we'll employ a free application named nRF Connect for Mobile, developed by Nordic Semi. This app is available on both Android ([[https://play.google.com/store/apps/details?id=no.nordicsemi.android.mcp&hl=en_US| Google Play Store]]) and iOS. To install the app, simply go to the Google Play Store or App Store, search for "nRF Connect for Mobile," and proceed with the installation.
+==== Sparrow BLE Service ====
+Here are the steps to create an BLE peripheral with an Environmental Sensing BLE service with temperature, humidity, and pressure, characteristics:
+  - Create a BLE device (server) with a name of your choice (we’ll call it ESP32_BME680, but you can call it any other name).
+  - Create an Environmental Sensing service (UUID: 0x181A).
+  - Add characteristics to that service: pressure (0x2A6D), temperature (0x2A6E) and humidity (0x246F)
+  - Add descriptors to the characteristics.
+  - Start the BLE server.
+  - Start advertising so BLE clients can connect and read the characteristics.
+  - Once a connection is established with a client, it will write new values on the characteristics and will notify the client, every time there’s a change.
+Copy the following code to the Arduino IDE, modify it and upload it to your board.
+<code C>
+#include <BLEDevice.h>
+#include <BLEServer.h>
+#include <BLEUtils.h>
+#include <BLE2902.h>
+#include "Zanshin_BME680.h"
+//BLE server name
+#define bleServerName "Sparrow_BME680"
+// Default UUID for Environmental Sensing Service
+// https://www.bluetooth.com/specifications/assigned-numbers/
+#define SERVICE_UUID (BLEUUID((uint16_t)0x181A))
+// Temperature Characteristic and Descriptor (default UUID)
+// Check the default UUIDs here: https://www.bluetooth.com/specifications/assigned-numbers/
+BLECharacteristic temperatureCharacteristic(BLEUUID((uint16_t)0x2A6E), BLECharacteristic::PROPERTY_NOTIFY);
+BLEDescriptor temperatureDescriptor(BLEUUID((uint16_t)0x2902));
+// Humidity Characteristic and Descriptor (default UUID)
+BLECharacteristic humidityCharacteristic(BLEUUID((uint16_t)0x2A6F), BLECharacteristic::PROPERTY_NOTIFY);
+BLEDescriptor humidityDescriptor(BLEUUID((uint16_t)0x2902));
+// Pressure Characteristic and Descriptor (default UUID)
+BLECharacteristic pressureCharacteristic(BLEUUID((uint16_t)0x2A6D), BLECharacteristic::PROPERTY_NOTIFY);
+BLEDescriptor pressureDescriptor(BLEUUID((uint16_t)0x2902));
+// Create a sensor object
+BME680_Class BME680;
+bool deviceConnected = false;
+//Setup callbacks onConnect and onDisconnect
+class MyServerCallbacks: public BLEServerCallbacks {
+  void onConnect(BLEServer* pServer) {
+    deviceConnected = true;
+    Serial.println("Device Connected");
+  };
+  void onDisconnect(BLEServer* pServer) {
+    deviceConnected = false;
+    Serial.println("Device Disconnected");
+  }
+};
+void setup() {
+  // Start serial communication
+  Serial.begin(115200);
+  // Start BME sensor
+  while (!BME680.begin(I2C_STANDARD_MODE)) {  // Start BME680 using I2C, use first device found
+    Serial.print(F("-  Unable to find BME680. Trying again in 5 seconds.\n"));
+    delay(5000);
+  }  // of loop until device is located
+  Serial.print(F("- Setting 16x oversampling for all sensors\n"));
+  BME680.setOversampling(TemperatureSensor, Oversample16);  // Use enumerated type values
+  BME680.setOversampling(HumiditySensor, Oversample16);     // Use enumerated type values
+  BME680.setOversampling(PressureSensor, Oversample16);     // Use enumerated type values
+  Serial.print(F("- Setting IIR filter to a value of 4 samples\n"));
+  BME680.setIIRFilter(IIR4);  // Use enumerated type values
+  Serial.print(F("- Setting gas measurement to 320\xC2\xB0\x43 for 150ms\n"));  // "degC" symbols
+  BME680.setGas(320, 150);  // 320 deg.C for 150 milliseconds
+  // Create the BLE Device
+  BLEDevice::init(bleServerName);
+  // Create the BLE Server
+  BLEServer *pServer = BLEDevice::createServer();
+  pServer->setCallbacks(new MyServerCallbacks());
+  // Create the BLE Service
+  BLEService *bmeService = pServer->createService(SERVICE_UUID);
+  // Create BLE Characteristics and corresponding Descriptors
+  bmeService->addCharacteristic(&temperatureCharacteristic);
+  temperatureCharacteristic.addDescriptor(&temperatureDescriptor);
+  bmeService->addCharacteristic(&humidityCharacteristic);
+  humidityCharacteristic.addDescriptor(&humidityDescriptor);
+  bmeService->addCharacteristic(&pressureCharacteristic);
+  pressureCharacteristic.addDescriptor(&pressureDescriptor);
+  // Start the service
+  bmeService->start();
+  // Start advertising
+  pServer->getAdvertising()->start();
+  Serial.println("Waiting a client connection to notify...");
+}
+void loop() {
+  if (deviceConnected) {
+  static int32_t  temp, hum, pres, gas;  // BME readings
+  BME680.getSensorData(temp, hum, pres, gas);  // Get readings
+  float t = (float)((int8_t)(temp / 100));
+  t += (float)((uint8_t)(temp % 100))/100.0;
+  float h = (float)((int8_t)(hum / 1000));
+  h += (float)((uint16_t)(hum % 1000)))/1000.0;
+  float p = (float)((int16_t)(pres / 100));
+  p += (float)((uint8_t)(pres % 100))/100.0;
+    //Notify temperature reading
+    uint16_t temperature = (uint16_t)t;
+    //Set temperature Characteristic value and notify connected client
+    temperatureCharacteristic.setValue(temperature);
+    temperatureCharacteristic.notify();
+    Serial.print("Temperature Celsius: ");
+    Serial.print(t);
+    Serial.println(" ºC");
+    //Notify humidity reading
+    uint16_t humidity = (uint16_t)h;
+    //Set humidity Characteristic value and notify connected client
+    humidityCharacteristic.setValue(humidity);
+    humidityCharacteristic.notify();
+    Serial.print("Humidity: ");
+    Serial.print(h);
+    Serial.println(" %");
+    //Notify pressure reading
+    uint16_t pressure = (uint16_t)p;
+    //Set humidity Characteristic value and notify connected client
+    pressureCharacteristic.setValue(pressure);
+    pressureCharacteristic.notify();
+    Serial.print("Pressure: ");
+    Serial.print(p);
+    Serial.println(" hPa");
+    delay(10000);
+  }
+}
+</code>
+Upload the code to your board. After uploading, open the Serial Monitor, and restart the Sparrow by pressing the RST/EN button.
+You should get a //"Waiting a client connection to notify..."// message in the Serial Monitor.
+Then, go to your smartphone, open the nRF Connect app from Nordic, and start scanning for new devices. You should find a device called **Sparrow_BME680**, this is the BLE server name you defined earlier.
+Connect to it. You’ll see that it displays the Environmental Sensing service with the temperature, humidity, and pressure characteristics. Click on the down arrows to activate the notifications.
+Then, click on the second icon (the one that looks like a " mark) at the left to change the format. You can change to unsigned int for all characteristics. You’ll start seeing the temperature, humidity, and pressure values being reported every 10 seconds.
+===== Web BLE Application =====
+Follow the tutorial [[https://randomnerdtutorials.com/esp32-web-bluetooth/| here]] to learn how to create a Web application that connects directly to your Sparrow ESP32 board. You can use the web app just like a normal phone application to send and receive information over BLE from your device.
+<note important>Web BLE is not currently supported by iOS phones </note>
+Build the application in the tutorial and deploy the web page in your GitHub account.
+=== Assignment ===
+<note> Modify the web page and the BLE app to display the BME680 sensor data (temperature, pressure and humidity). </note>