BLE UART Communication between XIAO ESP32C3 (client/central) and nRF52840 (server/peripheral), in Arduino Framework.

Last post I have a BLE UART Peripheral run on XIAO nRF52840 Sense (in Arduino Framework), in this post I implement client/Central side running on XIAO ESP32C3 (in Arduino Framework also), modified from  ESP32 BLE Arduino > BLE_client example.


Noted that the XIAO nRF52840 Sense server/Peripheral implemented a Nordic UART Service (NUS), so we have to use the matched UUIDs in client/Central side.
- Nordic UART Service (NUS) UUID (6E400001-B5A3-F393-E0A9-E50E24DCCA9E)
- RX Characteristic UUID (6E400002-B5A3-F393-E0A9-E50E24DCCA9E)
- TX Characteristic UUID (6E400003-B5A3-F393-E0A9-E50E24DCCA9E).

XESP32C3_BLE_client.ino 
/*
 * Modify Examples for XIAO_ESP32C3
 *        > ESP32 BLE Arduino 
 *        > BLE_client
 * Run on Xiao ESP32C3.
 * With UUID of Nordic UART Service (NUS), to work with 
 * XnRF52_bleuart_OLED_Terminal run on Xiao nRF52840 Sensse.
 * Read from Serial and send to BLE UART server/peripheral.
 */

/**
 * A BLE client example that is rich in capabilities.
 * There is a lot new capabilities implemented.
 * author unknown
 * updated by chegewara
 */

#include "BLEDevice.h"
//#include "BLEScan.h"

// UUID of Nordic UART Service (NUS)
#define SERVICE_UUID           "6E400001-B5A3-F393-E0A9-E50E24DCCA9E"
#define CHARACTERISTIC_UUID_RX "6E400002-B5A3-F393-E0A9-E50E24DCCA9E"
#define CHARACTERISTIC_UUID_TX "6E400003-B5A3-F393-E0A9-E50E24DCCA9E"

// The remote service we wish to connect to.
static BLEUUID serviceUUID(SERVICE_UUID);
// The characteristic of the remote service we are interested in.
static BLEUUID    charUUID_RX(CHARACTERISTIC_UUID_RX);

static boolean doConnect = false;
static boolean connected = false;
static boolean doScan = false;
static BLERemoteCharacteristic* pRemoteCharacteristic_RX;
static BLEAdvertisedDevice* myDevice;

static void notifyCallback(
  BLERemoteCharacteristic* pBLERemoteCharacteristic,
  uint8_t* pData,
  size_t length,
  bool isNotify) {
    Serial.print("Notify callback for characteristic ");
    Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
    Serial.print(" of data length ");
    Serial.println(length);
    Serial.print("data: ");
    Serial.println((char*)pData);
}

class MyClientCallback : public BLEClientCallbacks {
  void onConnect(BLEClient* pclient) {
  }

  void onDisconnect(BLEClient* pclient) {
    connected = false;
    Serial.println("onDisconnect");
  }
};

bool connectToServer() {
    Serial.print("Forming a connection to ");
    Serial.println(myDevice->getAddress().toString().c_str());
    
    BLEClient*  pClient  = BLEDevice::createClient();
    Serial.println(" - Created client");

    pClient->setClientCallbacks(new MyClientCallback());

    // Connect to the remove BLE Server.
    pClient->connect(myDevice);  // if you pass BLEAdvertisedDevice instead of address, it will be recognized type of peer device address (public or private)
    Serial.println(" - Connected to server");
    pClient->setMTU(517); //set client to request maximum MTU from server (default is 23 otherwise)
  
    // Obtain a reference to the service we are after in the remote BLE server.
    BLERemoteService* pRemoteService = pClient->getService(serviceUUID);
    if (pRemoteService == nullptr) {
      Serial.print("Failed to find our service UUID: ");
      Serial.println(serviceUUID.toString().c_str());
      pClient->disconnect();
      return false;
    }
    Serial.println(" - Found our service");


    // Obtain a reference to the characteristic in the service of the remote BLE server.
    pRemoteCharacteristic_RX = pRemoteService->getCharacteristic(charUUID_RX);
    if (pRemoteCharacteristic_RX == nullptr) {
      Serial.print("Failed to find our characteristic UUID: ");
      Serial.println(charUUID_RX.toString().c_str());
      pClient->disconnect();
      return false;
    }
    Serial.println(" - Found our characteristic");

    // Read the value of the characteristic.
    if(pRemoteCharacteristic_RX->canRead()) {
      std::string value = pRemoteCharacteristic_RX->readValue();
      Serial.print("The characteristic value was: ");
      Serial.println(value.c_str());
    }

    if(pRemoteCharacteristic_RX->canNotify())
      pRemoteCharacteristic_RX->registerForNotify(notifyCallback);

    connected = true;
    return true;
}
/**
 * Scan for BLE servers and find the first one that advertises the service we are looking for.
 */
class MyAdvertisedDeviceCallbacks: public BLEAdvertisedDeviceCallbacks {
 /**
   * Called for each advertising BLE server.
   */
  void onResult(BLEAdvertisedDevice advertisedDevice) {
    Serial.print("BLE Advertised Device found: ");
    Serial.println(advertisedDevice.toString().c_str());

    // We have found a device, let us now see if it contains the service we are looking for.
    if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID)) {

      BLEDevice::getScan()->stop();
      myDevice = new BLEAdvertisedDevice(advertisedDevice);
      doConnect = true;
      doScan = true;

    } // Found our server
  } // onResult
}; // MyAdvertisedDeviceCallbacks


void setup() {
  Serial.begin(115200);
  Serial.println("Starting Arduino BLE Client application...");
  BLEDevice::init("");

  // Retrieve a Scanner and set the callback we want to use to be informed when we
  // have detected a new device.  Specify that we want active scanning and start the
  // scan.
  BLEScan* pBLEScan = BLEDevice::getScan();
  pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
  pBLEScan->setInterval(1349);
  pBLEScan->setWindow(449);
  pBLEScan->setActiveScan(true);
  
  //pBLEScan->start(5, false);
  pBLEScan->start(0, false);

} // End of setup.


// This is the Arduino main loop function.
void loop() {
  

  // If the flag "doConnect" is true then we have scanned for and found the desired
  // BLE Server with which we wish to connect.  Now we connect to it.  Once we are 
  // connected we set the connected flag to be true.
  if (doConnect == true) {
    if (connectToServer()) {
      Serial.println("We are now connected to the BLE Server.");
    } else {
      Serial.println("We have failed to connect to the server; there is nothin more we will do.");
    }
    doConnect = false;
  }

  // If we are connected to a peer BLE Server, update the characteristic each time we are reached
  // with the current time since boot.
  if (connected) {
    /*
    String newValue = "Time since boot: " + String(millis()/1000);
    Serial.println("Setting new characteristic value to \"" + newValue + "\"");
    
    // Set the characteristic's value to be the array of bytes that is actually a string.
    pRemoteCharacteristic_RX->writeValue(newValue.c_str(), newValue.length());
    */

    if (Serial.available() > 0) {
      int incomingByte = Serial.read();
      Serial.println(incomingByte, DEC);
    if (connected) {
      pRemoteCharacteristic_RX->writeValue(incomingByte);  
    }
  }
  }else if(doScan){
    BLEDevice::getScan()->start(0);  // this is just example to start scan after disconnect, most likely there is better way to do it in arduino
  }
  
  delay(1000); // Delay a second between loops.
} // End of loop

XESP32C3_BLE_client_OLED_Terminal.ino 
/*
 * Modify Examples for XIAO_ESP32C3
 *        > ESP32 BLE Arduino 
 *        > BLE_client
 * Run on Xiao ESP32C3.
 * With UUID of Nordic UART Service (NUS), to work with 
 * XnRF52_bleuart_OLED_Terminal run on Xiao nRF52840 Sensse.
 * Read from Serial and send to BLE UART server/peripheral.
 * receive from BLE UART server/peripheral and display on OLED.
 */

/**
 * A BLE client example that is rich in capabilities.
 * There is a lot new capabilities implemented.
 * author unknown
 * updated by chegewara
 */

#include "BLEDevice.h"
//#include "BLEScan.h"
#include <Arduino.h>
#include <U8x8lib.h>

// UUID of Nordic UART Service (NUS)
// RX means rx in Server/Peripheral side, tx in Client/Central this side.
// TX means tx in Server/Peripheral side, rx in Client/Central this side.
#define SERVICE_UUID           "6E400001-B5A3-F393-E0A9-E50E24DCCA9E"
#define CHARACTERISTIC_UUID_RX "6E400002-B5A3-F393-E0A9-E50E24DCCA9E"
#define CHARACTERISTIC_UUID_TX "6E400003-B5A3-F393-E0A9-E50E24DCCA9E"

// The remote service we wish to connect to.
static BLEUUID serviceUUID(SERVICE_UUID);
// The characteristic of the remote service we are interested in.
static BLEUUID charUUID_RX(CHARACTERISTIC_UUID_RX);
static BLEUUID charUUID_TX(CHARACTERISTIC_UUID_TX);

static boolean doConnect = false;
static boolean connected = false;
static boolean doScan = false;
static BLERemoteCharacteristic* pRemoteCharacteristic_RX;
static BLERemoteCharacteristic* pRemoteCharacteristic_TX;
static BLEAdvertisedDevice* myDevice;

// U8x8 Contructor
U8X8_SSD1306_128X64_NONAME_HW_I2C u8x8(/* reset=*/ U8X8_PIN_NONE); 

// setup the terminal (U8X8LOG) and connect to u8g2 for automatic refresh of the display
// The size (width * height) depends on the display 
#define U8LOG_WIDTH 16
#define U8LOG_HEIGHT 8
uint8_t u8log_buffer[U8LOG_WIDTH*U8LOG_HEIGHT];
U8X8LOG u8x8log;

static void notifyCallback_RX(
  BLERemoteCharacteristic* pBLERemoteCharacteristic,
  uint8_t* pData,
  size_t length,
  bool isNotify) {
    Serial.print("Notify callback for characteristic ");
    Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
    Serial.print(" of data length ");
    Serial.println(length);
    Serial.print("data: ");
    Serial.println((char*)pData);
}

static void notifyCallback_TX(
  BLERemoteCharacteristic* pBLERemoteCharacteristic,
  uint8_t* pData,
  size_t length,
  bool isNotify) {
    Serial.print("Notify callback for characteristic ");
    Serial.print(pBLERemoteCharacteristic->getUUID().toString().c_str());
    Serial.print(" of data length ");
    Serial.println(length);
    Serial.print("data: ");
    Serial.println((char*)pData);

    String strData = (char*)pData;
    u8x8log.print(strData);
}

class MyClientCallback : public BLEClientCallbacks {
  void onConnect(BLEClient* pclient) {
  }

  void onDisconnect(BLEClient* pclient) {
    connected = false;
    Serial.println("onDisconnect");
  }
};

bool connectToServer() {
    Serial.print("Forming a connection to ");
    Serial.println(myDevice->getAddress().toString().c_str());
    
    BLEClient*  pClient  = BLEDevice::createClient();
    Serial.println(" - Created client");

    pClient->setClientCallbacks(new MyClientCallback());

    // Connect to the remove BLE Server.
    pClient->connect(myDevice);  // if you pass BLEAdvertisedDevice instead of address, it will be recognized type of peer device address (public or private)
    Serial.println(" - Connected to server");
    pClient->setMTU(517); //set client to request maximum MTU from server (default is 23 otherwise)
  
    // Obtain a reference to the service we are after in the remote BLE server.
    BLERemoteService* pRemoteService = pClient->getService(serviceUUID);
    if (pRemoteService == nullptr) {
      Serial.print("Failed to find our service UUID: ");
      Serial.println(serviceUUID.toString().c_str());
      pClient->disconnect();
      return false;
    }
    Serial.println(" - Found our service");


    // Obtain a reference to the characteristic in the service of the remote BLE server.
    pRemoteCharacteristic_RX = pRemoteService->getCharacteristic(charUUID_RX);
    pRemoteCharacteristic_TX = pRemoteService->getCharacteristic(charUUID_TX);
    boolean success_to_find_char = true;
    if (pRemoteCharacteristic_RX == nullptr) {
      Serial.print("Failed to find our characteristic UUID: ");
      Serial.println(charUUID_RX.toString().c_str());
      //pClient->disconnect();
      //return false;
      success_to_find_char = false;
    }else{
      Serial.print("Success to find our characteristic UUID: ");
      Serial.println(charUUID_RX.toString().c_str());
    }
    
    if (pRemoteCharacteristic_TX == nullptr) {
      Serial.print("Failed to find our characteristic UUID: ");
      Serial.println(charUUID_TX.toString().c_str());
      //pClient->disconnect();
      //return false;
      success_to_find_char = false;
    }else{
      Serial.print("Success to find our characteristic UUID: ");
      Serial.println(charUUID_TX.toString().c_str());
    }
    if (success_to_find_char == false){
      pClient->disconnect();
      return false;
    }
    Serial.println(" - Found our characteristic");

    // Read the value of the characteristic.
    if(pRemoteCharacteristic_RX->canRead()) {
      std::string value = pRemoteCharacteristic_RX->readValue();
      Serial.print("pRemoteCharacteristic_RX value was: ");
      Serial.println(value.c_str());
    }
    if(pRemoteCharacteristic_TX->canRead()) {
      std::string value = pRemoteCharacteristic_TX->readValue();
      Serial.print("pRemoteCharacteristic_TX value was: ");
      Serial.println(value.c_str());
    }

    if(pRemoteCharacteristic_RX->canNotify())
      pRemoteCharacteristic_RX->registerForNotify(notifyCallback_RX);
    if(pRemoteCharacteristic_TX->canNotify())
      pRemoteCharacteristic_TX->registerForNotify(notifyCallback_TX);

    connected = true;
    return true;
}
/**
 * Scan for BLE servers and find the first one that advertises the service we are looking for.
 */
class MyAdvertisedDeviceCallbacks: public BLEAdvertisedDeviceCallbacks {
 /**
   * Called for each advertising BLE server.
   */
  void onResult(BLEAdvertisedDevice advertisedDevice) {
    Serial.print("BLE Advertised Device found: ");
    Serial.println(advertisedDevice.toString().c_str());

    // We have found a device, let us now see if it contains the service we are looking for.
    if (advertisedDevice.haveServiceUUID() && advertisedDevice.isAdvertisingService(serviceUUID)) {

      BLEDevice::getScan()->stop();
      myDevice = new BLEAdvertisedDevice(advertisedDevice);
      doConnect = true;
      doScan = true;

    } // Found our server
  } // onResult
}; // MyAdvertisedDeviceCallbacks


void setup() {
  Serial.begin(115200);
  Serial.println("Starting Arduino BLE Client application...");

  u8x8.begin();
  u8x8.setFont(u8x8_font_chroma48medium8_r);
  
  u8x8log.begin(u8x8, U8LOG_WIDTH, U8LOG_HEIGHT, u8log_buffer);
  u8x8log.setRedrawMode(1);    // 0: Update screen with newline, 1: Update screen for every char  

  u8x8log.println("- Xiao ESP323 BLE UART client exercise -");
  u8x8log.println();
  
  BLEDevice::init("");

  // Retrieve a Scanner and set the callback we want to use to be informed when we
  // have detected a new device.  Specify that we want active scanning and start the
  // scan.
  BLEScan* pBLEScan = BLEDevice::getScan();
  pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
  pBLEScan->setInterval(1349);
  pBLEScan->setWindow(449);
  pBLEScan->setActiveScan(true);
  
  //pBLEScan->start(5, false);
  pBLEScan->start(0, false);

} // End of setup.


// This is the Arduino main loop function.
void loop() {
  

  // If the flag "doConnect" is true then we have scanned for and found the desired
  // BLE Server with which we wish to connect.  Now we connect to it.  Once we are 
  // connected we set the connected flag to be true.
  if (doConnect == true) {
    if (connectToServer()) {
      Serial.println("We are now connected to the BLE Server.");
    } else {
      Serial.println("We have failed to connect to the server; there is nothin more we will do.");
    }
    doConnect = false;
  }

  // If we are connected to a peer BLE Server, update the characteristic each time we are reached
  // with the current time since boot.
  if (connected) {
    /*
    String newValue = "Time since boot: " + String(millis()/1000);
    Serial.println("Setting new characteristic value to \"" + newValue + "\"");
    
    // Set the characteristic's value to be the array of bytes that is actually a string.
    pRemoteCharacteristic_RX->writeValue(newValue.c_str(), newValue.length());
    */

    if (Serial.available() > 0) {
      int incomingByte = Serial.read();
      //Serial.println(incomingByte, DEC);
    if (connected) {
      pRemoteCharacteristic_RX->writeValue(incomingByte);  
    }
  }
  }else if(doScan){
    BLEDevice::getScan()->start(0);  // this is just example to start scan after disconnect, most likely there is better way to do it in arduino
  }
  
  delay(1000); // Delay a second between loops.
} // End of loop

next:
~  Implement the server/peripheral side on NodeMCU ESP-C3-32S-Kit with SSD1331 SPI Color OLED.


Comments

Post a Comment

Popular posts from this blog

480x320 TFT/ILI9488 SPI wih EP32C3 (arduino-esp32) using Arduino_GFX Library

Image
Display on 3.5 inch 480x320 TFT with SPI ILI9488 (SKU:MSP3520) with XIAO EP32C3 (arduino-esp32) using Arduino_GFX Library. Install GFX Library for Arduino (Arduino_GFX) in Library Manager. Arduino_GFX is a Arduino graphics library supporting various displays with various data bus interfaces. This library start rewrite from Adafruit_GFX, LovyanGFX, TFT_eSPI, Ucglib, and more... Connection:      Connection between XIAO ESP32C3 and      3.5" 480x320 TFT with SPI ILI9488 (SKU:MSP3520)      XIAO ESP32C3                        +-------------+           +---------|GPIO2    5V      |          | +-----|GPIO3    GND    |-----------+ | +-|-----|GPIO4    3V3    |---------+ | | | | +---|GPIO5    GPIO10|-----...
Read more

my dev.tools - FNIRSI 2C23T 3-in-1 Dual Channel Oscilloscope/Multimeter/Signal Generator

Image
FNIRSI 2C23T 3-in-1 Dual Channel Oscilloscope/Multimeter/Signal Generator Steps to upgrade of FNIRSI 2C23T 3-in-1 : Remark@2024-03-23: Please check the comment by dmitriivanov5330 in the video. How to distinguish the hardware? please press menu , and if you can see the words in Setting: "Hardware version No.:XXXXX " then the device is made with latest hardware, it has the latest firmware, and now it doesn't need to upgrade.  If you can not see the words in Setting: "Hardware version No.:XXXXX ", then it is made with old hardware, and it can be upgraded with firmware 2.0.2, and if you confirm this, the firmware for the device with old hardware is attached.  By the way, the firmware 2.0.2 only fixes device with old hardware. The device with new hardware can not use this firmware to upgrade. - Download firmware from FNIRSI Official Web Site - Connect USB to PC - While 2C23T is OFF, press and hold MENU button, then press POWER button to power...
Read more