M5Atom(ESP32を含む)でHRセンサーデータを受信する(Arduino版)

2020/8/9:
ChestTypeとWristTypeの両方対応にスケッチを改善した。

2020/8/8+

PlatformIO M5Atom BLE HR Sensor Receiver

PlatformIO M5Atom BLE HR Sensor Receiver

概要

M5Atom(ESP32を含む)でHRセンサーデータを受信する(Arduino版)
開発ツールのインストールについては「M5Atomを開発ツールPlatformIOで使う(M5Atom/Arduino版)」を参照のこと。 (ホストPCとしてはubuntuを想定している)

platformio.ini

platformio.iniを以下のように編集する：

  ; PlatformIO Project Configuration File
  ;
  ;   Build options: build flags, source filter
  ;   Upload options: custom upload port, speed and extra flags
  ;   Library options: dependencies, extra library storages
  ;   Advanced options: extra scripting
  ;
  ; Please visit documentation for the other options and examples
  ; https://docs.platformio.org/page/projectconf.html

  [env:esp32dev]
  platform = espressif32
  board = m5stick-c
  framework = arduino

  monitor_speed = 115200

  lib_deps =
      # use M5Atom lib
      3113
      # use "FastLED"
      126

  lib_ldf_mode = deep+

  

M5Atom特有のライブラリを使用していないので、ESP32で動作させる場合は 通常のESP32のplatformio.iniで良い。

テスト用スケッチをダウンロードする

  cd src
  wget https://cdn.hackaday.io/files/880553767345120/Pulse.ino
  

テスト・スケッチ

ダウンロードしたスケッチを以下の修正点に対応して変更する：

修正点:
(1)余計なスペースを削除する
(2)Wrist-TypeのHRセンサー対応を追加する
(3)HRデータを表示する際、タイムスタンプ表示を追加する
(4)LED点滅をコメントアウトする

src/Pluse.ino(編集済み)
#余計なスペースを削除するなど大幅な修正になっているので
#オリジナルを修正するよりも、以下の修正済みのものをコピー＆ペーストすることを勧める：

  // modified/bufix 2020/8/9 by: xshige
  #define CHEST
  //#define WRIST

  // fix info:
  //   https://github.com/nkolban/esp32-snippets/issues/837
  //   Using BLE for Heart Rate Monitors, newer belts don't work #837

  unsigned long startMillis;

  /************************************************************************/
  /****************** Heart Rate BLE gateway for Technogym ****************/
  /************ Outputs a 30 ms pulse at recieved HR frequency ************/
  /**************** Indicates the remote HR battery level *****************/
  /*********************** Vincent HORN - march 2018 **********************/
  /**************************** version 1.0 *******************************/

  #include "BLEDevice.h"

  // Device connection
  static BLEAddress *pServerAddress;
  BLEClient*  pClient;
  static boolean doConnect = false;
  static boolean isconnect = false;

  // The remote HR service & characteristic
  static BLEUUID service_HR_UUID(BLEUUID((uint16_t)0x180D));
  static BLEUUID char_HR_UUID(BLEUUID((uint16_t)0x2A37));
  static BLERemoteCharacteristic* pRemote_HR_Characteristic;
  const uint8_t notificationOn[] = {0x1, 0x0};

  // HR Pulse timer
  hw_timer_t * timer = NULL; // Timer 
  volatile SemaphoreHandle_t timerSemaphore; // Timer 
  portMUX_TYPE timerMux = portMUX_INITIALIZER_UNLOCKED;// Timer 
  volatile uint32_t isrCounter = 0; // Timer 
  volatile uint32_t lastIsrAt = 0; // Timer 

  // HR Pulse output
  int ms_pb = 500; //millis per beat
  const int pulse_pin = 23; // pulse output pin
  bool pulse_on = false; // flag when pulse have to be fired
  unsigned long pulse_off_at = 0; // Time to stop the pulse

  // The remote BATT service a characteristic
  static BLEUUID service_BATT_UUID(BLEUUID((uint16_t)0x180F));
  static BLEUUID char_BATT_UUID(BLEUUID((uint16_t)0x2A19));
  static BLERemoteCharacteristic* pRemote_BATT_Characteristic;

  // BATT indicator
  const int battery_scan = 60000; // Scan interval in msec.
  unsigned long batt_read_start_at = 0;
  bool batt_indicator = false; // time to indicate de battery level
  int batt_flash = 0; // number of flash
  int i_flash = 1; // flash counter
  bool init_time = true; // flag for init on/off time  
  unsigned long on_at = 0; // Time to turn LED ON
  unsigned long off_at = 0; // Time to turn LED OFF
  const int led_pin = 22; // Battery indicator LED

  static void notifyCallback(BLERemoteCharacteristic* pBLERemoteCharacteristic, uint8_t* pData, size_t length, bool isNotify) {

      uint8_t HR_val = 0; // RAW HR value

          //< support both Chest/Wrist type 2020/8/9 by: xshige
      //if (pData[0] == 22 || pData[0] == 6) {
      if (pData[0] == 16) { // for Chest Type HR sensor (Polar H10)  
          if (pData[1] > 10 && pData[1] < 254) {// HR must be between 10 and 254 bpm
              HR_val = pData[1];
          } else HR_val =0;
      } else if (pData[0] == 0) { // for Wrist Type HR sensor  (Polar A370, OH1)
          if (pData[1] > 10 && pData[1] < 254) {// HR must be between 10 and 254 bpm
              HR_val = pData[1];
          } else HR_val =0;
      } else HR_val = 0;
          //>

  // display timestamp(sec)
  unsigned long currentMillis = millis()-startMillis;
  //Serial.println(pData[0]);
  Serial.print(currentMillis/1000);
  Serial.print(": ");
  //
      Serial.print("HR : ");
      Serial.print(HR_val);
      Serial.print(" bpm \t Battery : ");
      Serial.print(batt_flash*10);
      Serial.println(" %");

      if (HR_val != 0) {ms_pb = (int)60000/HR_val;} 
          // interval in ms between 2 heart beat if no value (zero) is recieved, ms_pb is set to 100s

  }

  bool connectToServer(BLEAddress pAddress) {

      Serial.print("Forming a connection to ");
      Serial.println(pAddress.toString().c_str());

      // create a new client
      pClient  = BLEDevice::createClient();
      Serial.println("Created client");

      // Connect to the remove BLE Server.
  #ifdef CHEST
          pClient->connect(pAddress, (esp_ble_addr_type_t)1); // bug fix 2020/8/9 (Chest type can be OK)
  #endif
  #ifdef WRIST
      pClient->connect(pAddress); // Chest can Not be OK
  #endif

      Serial.println("Connected to server");

      // Obtain a reference to the HR service of the remote BLE server.
      BLERemoteService* pRemote_HR_Service = pClient->getService(service_HR_UUID);
      if (pRemote_HR_Service == nullptr) {
          Serial.print("Failed to find HR service : ");
          //Serial.println(service_HR_UUID.toString().c_str());
          return false;
      } else Serial.println("Found HR service");

      // Obtain a reference to the BATT service of the remote BLE server.
      BLERemoteService* pRemote_BATT_Service = pClient->getService(service_BATT_UUID);
      if (pRemote_BATT_Service == nullptr) {
          Serial.print("Failed to find BATT service : ");
          //Serial.println(service_BATT_UUID.toString().c_str());
          return false;
      } else Serial.println("Found BATT service");

      // Obtain a reference to the HR characteristic in the service of the remote BLE server.
      pRemote_HR_Characteristic = pRemote_HR_Service->getCharacteristic(char_HR_UUID);
      if (pRemote_HR_Characteristic == nullptr) {
          Serial.print("Failed to find HR characteristic : ");
          //Serial.println(char_HR_UUID.toString().c_str());
          return false;
      } else Serial.println("Found HR characteristic");

      // Obtain a reference to the BATT characteristic in the service of the remote BLE server.
      pRemote_BATT_Characteristic = pRemote_BATT_Service->getCharacteristic(char_BATT_UUID);
      if (pRemote_BATT_Characteristic == nullptr) {
          Serial.print("Failed to find BATT characteristic : ");
          //Serial.println(char_BATT_UUID.toString().c_str());
          return false;
      } else Serial.println("Found BATT characteristic");

      // Set notification
      pRemote_HR_Characteristic->registerForNotify(notifyCallback);
      pRemote_HR_Characteristic->getDescriptor(BLEUUID((uint16_t)0x2902))->writeValue((uint8_t*)notificationOn, 2, true);

  }

  class MyAdvertisedDeviceCallbacks: public BLEAdvertisedDeviceCallbacks {

      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.getServiceUUID().equals(service_HR_UUID)) {

              Serial.println("Found Heart Rate device! ");
              advertisedDevice.getScan()->stop();

              pServerAddress = new BLEAddress(advertisedDevice.getAddress());
              doConnect = true;
          } 
      }
  };

  void device_scan(){

      // 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 to run for 15 seconds.

      BLEScan* pBLEScan = BLEDevice::getScan();
      pBLEScan->setAdvertisedDeviceCallbacks(new MyAdvertisedDeviceCallbacks());
      pBLEScan->setActiveScan(true);

      while (!doConnect) {
          // Scan till a connection is found
          Serial.println("Scanning for BLE devices ...");
          BLEScanResults foundDevices = pBLEScan->start(15);
          Serial.print("Devices found: ");
          Serial.println(foundDevices.getCount());
      }
  }

  void IRAM_ATTR onTimer(){

      // Increment the counter and set the time of ISR
      portENTER_CRITICAL_ISR(&timerMux);
      isrCounter++;
      lastIsrAt = millis();
      portEXIT_CRITICAL_ISR(&timerMux);

      // Give a semaphore that we can check in the loop
      xSemaphoreGiveFromISR(timerSemaphore, NULL);
      // It is safe to use digitalRead/Write here if you want to toggle an output
  }

  void setup() {

      Serial.begin(115200);
      Serial.println("------------------------------------------");
      Serial.println("Starting Arduino BLE Client application...");

      // initialize pulse_pin as an output
      //pinMode(pulse_pin, OUTPUT);

      // initialize battery pin led as an output
      //pinMode(led_pin, OUTPUT);

      // initialize timer 
      timerSemaphore = xSemaphoreCreateBinary(); // Create semaphore to inform us when the timer has fired
      timer = timerBegin(0, 80, true);

      // Attach onTimer function to our timer.
      timerAttachInterrupt(timer, &onTimer, true);

      // initialize BLE 
      BLEDevice::init("");

      // Scan for devices
      device_scan();

  startMillis = millis();

  }

  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.  
      if (doConnect == true) {
          if (connectToServer(*pServerAddress)) {

              Serial.println("Connected to the BLE Server.");
              isconnect = true;

              // First timer set to 10 sec.
              timerAlarmWrite(timer, 10000000, true);
              timerAlarmEnable(timer);

          } else {
              Serial.println("We have failed to connect to the server; there is nothin more we will do.");
              isconnect = false;
          }
          doConnect = false;
      }

      // when interrupt occurres
      if (xSemaphoreTake(timerSemaphore, 0) == pdTRUE){
          uint32_t isrCount = 0, isrTime = 0;

          // Read the interrupt count and time
          portENTER_CRITICAL(&timerMux);
          isrTime = lastIsrAt;
          isrCount = isrCounter;
          portEXIT_CRITICAL(&timerMux);

          // create a 30 ms pulse on pulse_pin 
          pulse_on = true;
          pulse_off_at = millis() + 30;

          //digitalWrite(pulse_pin, HIGH);
          //delay(30);
          //digitalWrite(pulse_pin, LOW);

          // rearm the timer with previous incomming ms per beat (ms_pb) value
          timerAlarmDisable(timer);
          timerAlarmWrite(timer, 1000*ms_pb, true);
          timerAlarmEnable(timer);

          /*
          Serial.print("at ");
          Serial.print(isrTime);
          Serial.print(" ms");
          Serial.print("\t new timer ");
          Serial.print(ms_pb);
          Serial.println(" ms");
          */
      }

      // Create Pulse 
      if (pulse_on) {
          if (millis() < pulse_off_at) {
              //digitalWrite(PULSE_PIN, HIGH);   // turn the LED on (HIGH is the voltage level)
          }
          else {
              //digitalWrite(PULSE_PIN, LOW);    // turn the LED off by making the voltage LOW
              pulse_on = false;
          }
      }


      // Read the value of the battery level characteristic each battery_scan ms (only if connected)
      if (isconnect && (millis()-batt_read_start_at > battery_scan)) {
          std::string value = pRemote_BATT_Characteristic->readValue();
          String batt_caracteristic = value.c_str();

          // convert string to char
          char buf[2];
          batt_caracteristic.toCharArray(buf, 2);

          // BATT_val is the numeric ASCII value
          int BATT_val = int(buf[0]);

          // batt_flash number of flash (30% battery => 3 flashs)
          batt_flash = (int)BATT_val/10;

          // fire the LED
          batt_indicator = true;

          batt_read_start_at = millis();
      }

      // Battery indicator
      if (batt_indicator){

          if (i_flash <= batt_flash){

              if (init_time){
                  off_at = millis() + 40;
                  on_at = off_at + 500;
                  init_time = false;
              }

              if (millis() <= off_at){
                  digitalWrite(led_pin, HIGH);
              }

              if ((millis() > off_at) && (millis() <= on_at)){
                  digitalWrite(led_pin, LOW);
              } else if (millis() > on_at){
                  init_time = true;
                  i_flash++;
              }

          } else {
              i_flash = 1;
              batt_indicator = false;
          }
      }

      // Watch if client is still connected. When not reboot ESP32
      if (pClient->isConnected() == false) {
          Serial.println("Device disconnected ! ESP 32 rebooting .....");
          ESP.restart();
      }
  }
  

使用するHRセンサーのタイプで以下の#defineのうち一つを有効にして、コンパイル＆実行する。

  #define CHEST
  #define WRIST
  

書き込み後、実行するとBLEデバイスをスキャンしてHRセンサーが見つかれば自動的にペアリングして、HRデータを表示する。 既にHRセンサーが（スマフォなどと）ペアリング済みだと接続できないので、その場合、該当のスマフォのペアリングを解除する。

出力例：(Polar A370の場合)

picocom /dev/ttyUSB0 -b115200

  Starting Arduino BLE Client application...
  Scanning for BLE devices ...
  BLE Advertised Device found: Name: Polar A370 1D44A125, Address: a0:9e:1a:1d:44:a1, manufacturer data: 6b002f0000, serviceUUID: 0000180d-0000-1000-8000-00805f9b34fb
  Found Heart Rate device! 
  Devices found: 1
  Forming a connection to a0:9e:1a:1d:44:a1
  Created client
  Connected to server
  Found HR service
  Found BATT service
  Found HR characteristic
  Found BATT characteristic
  Connected to the BLE Server.
  1: HR : 69 bpm     Battery : 0 %
  2: HR : 69 bpm     Battery : 0 %
  3: HR : 70 bpm     Battery : 0 %
  4: HR : 70 bpm     Battery : 0 %
  5: HR : 69 bpm     Battery : 0 %
  6: HR : 69 bpm     Battery : 0 %
  7: HR : 70 bpm     Battery : 0 %
  8: HR : 70 bpm     Battery : 0 %
  9: HR : 70 bpm     Battery : 0 %
  # バッテリ残量が0%なのは、バッテリ残量を取得するのに時間がかかるせいのようだ。
  # 待っていると自動的に表示されるようになる。
  

出力例：(Polar H10の場合)

  picocom /dev/ttyUSB0 -b115200

  Starting Arduino BLE Client application...
  Scanning for BLE devices ...
  BLE Advertised Device found: Name: , Address: 7d:01:bf:c3:6f:ff, manufacturer data: 4c0010050318e24cea
  BLE Advertised Device found: Name: Polar H10 31BFD72E, Address: fd:e0:ff:99:cc:1e, manufacturer data: 6b00330c4243
  Devices found: 2
  Scanning for BLE devices ...
  BLE Advertised Device found: Name: , Address: fd:e0:ff:99:cc:1e, manufacturer data: 6b002f0c4343, serviceUUID: 0000180d-0000-1000-8000-00805f9b34fb, txPower: 4
  Found Heart Rate device! 
  Devices found: 1
  Forming a connection to fd:e0:ff:99:cc:1e
  Created client
  Connected to server
  Found HR service
  Found BATT service
  [E][BLERemoteCharacteristic.cpp:274] retrieveDescriptors(): esp_ble_gattc_get_all_descr: Unknown
  Found HR characteristic
  Found BATT characteristic
  Connected to the BLE Server.
  2: HR : 67 bpm     Battery : 0 %
  3: HR : 66 bpm     Battery : 0 %
  4: HR : 66 bpm     Battery : 0 %
  5: HR : 66 bpm     Battery : 0 %
  6: HR : 66 bpm     Battery : 0 %
  7: HR : 66 bpm     Battery : 0 %
  8: HR : 66 bpm     Battery : 0 %
  9: HR : 67 bpm     Battery : 0 %
  # バッテリ残量が0%なのは、バッテリ残量を取得するのに時間がかかるせいのようだ。
  # 待っていると自動的に表示されるようになる。
  

参考情報

https://hackaday.io/project/88055-technogym-new-heart-rate-ble-sensor
Technogym : new Heart Rate BLE sensor
Replace the RF HR receiver with a new BLE sensor based on ESP32.

Web-BluetoothでHRセンサーを接続する
Web-Bluetooth:HR(心拍)センサーのロガー
Web-Bluetooth:CSC(自転車)センサーのロガー

PlatformIO Core (CLI)

以上