1  """
 2  Read heart rate data from a heart rate peripheral using the standard BLE
 3  Heart Rate service.
 4  """
 5  
 6  import time
 7  
 8  import adafruit_ble
 9  from adafruit_ble.advertising.standard import ProvideServicesAdvertisement
10  from adafruit_ble.services.standard.device_info import DeviceInfoService
11  from adafruit_ble_heart_rate import HeartRateService
12  
13  # PyLint can't find BLERadio for some reason so special case it here.
14  ble = adafruit_ble.BLERadio()  # pylint: disable=no-member
15  
16  hr_connection = None
17  # Start with a fresh connection.
18  if ble.connected:
19      for connection in ble.connections:
20          if HeartRateService in connection:
21              connection.disconnect()
22          break
23  
24  while True:
25      print("Scanning...")
26      for adv in ble.start_scan(ProvideServicesAdvertisement, timeout=5):
27          if HeartRateService in adv.services:
28              print("found a HeartRateService advertisement")
29              hr_connection = ble.connect(adv)
30              print("Connected")
31              break
32  
33      # Stop scanning whether or not we are connected.
34      ble.stop_scan()
35      print("Stopped scan")
36  
37      if hr_connection and hr_connection.connected:
38          print("Fetch connection")
39          if DeviceInfoService in hr_connection:
40              dis = hr_connection[DeviceInfoService]
41              try:
42                  manufacturer = dis.manufacturer
43              except AttributeError:
44                  manufacturer = "(Manufacturer Not specified)"
45              try:
46                  model_number = dis.model_number
47              except AttributeError:
48                  model_number = "(Model number not specified)"
49              print("Device:", manufacturer, model_number)
50          else:
51              print("No device information")
52          hr_service = hr_connection[HeartRateService]
53          print("Location:", hr_service.location)
54          while hr_connection.connected:
55              print(hr_service.measurement_values)
56              time.sleep(1)