Python3环境，树莓派使用bluepy与BLE设备通信

扫描设备

创建一个ScanDelegate

1 class ScanDelegate(DefaultDelegate):
2     def __init__(self):
3         DefaultDelegate.__init__(self)
4
5     def handleDiscovery(self, dev, isNewDev, isNewData):
6         if isNewDev:
7             print("Discovered device", dev.addr)
8         elif isNewData:
9             print("Received new data from", dev.addr)

扫描设备并打印

 1 scanner = Scanner().withDelegate(ScanDelegate())
 2 devices = scanner.scan(10.0)
 3 creyond_devices = []
 4 for dev in devices:
 5     print("Device %s (%s), RSSI=%d dB" % (dev.addr, dev.addrType, dev.rssi))
 6     for (adtype, desc, value) in dev.getScanData():
 7         if value == "CreYond":
 8             creyond_devices.append(dev)
 9         print("  %s = %s" % (desc, value))
10
11 print(creyond_devices)

获取Services与Characteristics

通过Peripheral来获取Services

1 c_device = creyond_devices[0]
2 p_device = Peripheral(c_device)
3 p_device.withDelegate(NotifyDelegate(p_device))
4 services = p_device.getServices()
5
6 # displays all services
7 for service in services:
8     print(service)

通过UUID获取指定Service　　

1 service_uuid = UUID("00000010-3354-4d64-6e6f-XXXXXXX3534a")
2 c_service = p_device.getServiceByUUID(service_uuid)
3 print(c_service)

获取Service下的Characteristics

1 characteristics = c_service.getCharacteristics()
2 # displays all characteristics
3 for char in characteristics:
4     print(char)

订阅与通知

创建一个NotifyDelegate

1 class NotifyDelegate(DefaultDelegate):
2     # Constructor (run once on startup)
3     def __init__(self, params):
4         DefaultDelegate.__init__(self)
5
6     # func is caled on notifications
7     def handleNotification(self, cHandle, data):
8         print("Notification from Handle: 0x" + format(cHandle,'02X') )
9         print(hexlify(data))

在创建Peripheral时，指定

1 p_device.withDelegate(NotifyDelegate(p_device))

查找descriptor，并设定其值为1.设定值时注意大小端 bytes([1, 0])。注意，直接写characteristic是错误的，一定要找到characteristic下的UUID为0x2902的descriptor。部分蓝牙设备的UUID可能不规范，通过UUID查找可能存在重复，建议getDescriptors筛选好对应范围。

1 hEcg=notify_char.getHandle()
2 for descriptor in p_device.getDescriptors(hEcg,c_service.hndEnd):
3     if (descriptor.uuid==0x2902):
4         print(f'Client Characteristic Configuration found at handle 0x{format(descriptor.handle,"02X")}')
5         hEcgCCC=descriptor.handle
6
7 p_device.writeCharacteristic(hEcgCCC,bytes([1, 0]))

等待显示：

1 while True:
2     if p_device.waitForNotifications(1.0):
3         # handleNotification() was called
4         continue
5
6     print("Waiting... Waited more than one sec for notification")

完整代码：

 1 # %%
 2 from bluepy.btle import Scanner, DefaultDelegate,UUID, Peripheral
 3 from binascii import hexlify
 4 import struct
 5 # %%
 6 class ScanDelegate(DefaultDelegate):
 7     def __init__(self):
 8         DefaultDelegate.__init__(self)
 9
10     def handleDiscovery(self, dev, isNewDev, isNewData):
11         if isNewDev:
12             print("Discovered device", dev.addr)
13         elif isNewData:
14             print("Received new data from", dev.addr)
15
16
17 class NotifyDelegate(DefaultDelegate):
18     # Constructor (run once on startup)
19     def __init__(self, params):
20         DefaultDelegate.__init__(self)
21
22     # func is caled on notifications
23     def handleNotification(self, cHandle, data):
24         print("Notification from Handle: 0x" + format(cHandle,'02X') )
25         print(hexlify(data))
26
27
28 # %%
29 scanner = Scanner().withDelegate(ScanDelegate())
30 devices = scanner.scan(10.0)
31 creyond_devices = []
32 for dev in devices:
33     print("Device %s (%s), RSSI=%d dB" % (dev.addr, dev.addrType, dev.rssi))
34     for (adtype, desc, value) in dev.getScanData():
35         if value == "CreYond":
36             creyond_devices.append(dev)
37         print("  %s = %s" % (desc, value))
38
39 print(creyond_devices)
40 # %% get services
41 # the first device name CreYond
42 c_device = creyond_devices[0]
43 p_device = Peripheral(c_device)
44 p_device.withDelegate(NotifyDelegate(p_device))
45 services = p_device.getServices()
46
47 # displays all services
48 for service in services:
49     print(service)
50 # %% get specified service
51 service_uuid = UUID("00000010-3354-4d64-6e6f-xxxxxxxxx534a")
52 c_service = p_device.getServiceByUUID(service_uuid)
53 print(c_service)
54
55 # %%
56 characteristics = c_service.getCharacteristics()
57 # displays all characteristics
58 for char in characteristics:
59     print(char)
60 # %%
61 notify_char = characteristics[0]
62
63 #%%
64 hEcg=notify_char.getHandle()
65 for descriptor in p_device.getDescriptors(hEcg,c_service.hndEnd):
66     if (descriptor.uuid==0x2902):
67         print(f'Client Characteristic Configuration found at handle 0x{format(descriptor.handle,"02X")}')
68         hEcgCCC=descriptor.handle
69
70 p_device.writeCharacteristic(hEcgCCC,bytes([1, 0]))
71
72 #%%
73 tmp_data=p_device.readCharacteristic(0x11)
74 print(tmp_data)
75 # %%
76 while True:
77     if p_device.waitForNotifications(1.0):
78         # handleNotification() was called
79         continue
80
81     print("Waiting... Waited more than one sec for notification")
82
83 # %%
84 p_device.disconnect()
85
86 # %%

参考链接：

【Bluetooth LE】Bluez中Bluetoothctl指令详解（连接iPhone为例）

bluepy官方Demo

RPi Bluetooth LE

github demo