蓝牙学习3（简易蓝牙控制）（TODO）

硬件平台用的ESP32 C3 + nRF Connect（小米手机）

这次还是先用micopython，主要是来的快，先对整体概念简建立一些感性认识。

1 蓝牙广播

python 复制代码

import bluetooth

# 1. 复位蓝牙，避免残留状态
ble = bluetooth.BLE()
ble.active(False)
import utime
utime.sleep_ms(100)
ble.active(True)

# 设备名称
dev_name = "C3-DEV"
# 标准BLE广播帧：Flags+设备名（固定格式，手机必扫到）
# 0x02,0x01,0x06 = BLE通用发现标志
adv_data = bytearray([0x02,0x01,0x06, len(dev_name)+1, 0x09]) + dev_name.encode()

# 开启广播：间隔100000us=100ms，可连接模式
ble.gap_advertise(100000, adv_data=adv_data, connectable=True)

print("BLE广播开启，设备名:C3-DEV")

2 蓝牙点灯

python 复制代码

import bluetooth
import machine
import time
from micropython import const

# 1. 配置板载 LED（ESP32-C3 常用引脚为 8，根据实际板子可调整）
LED_PIN = 8
led = machine.Pin(LED_PIN, machine.Pin.OUT)
led.value(0) # 默认灭

# 2. BLE 事件常量定义
_IRQ_CENTRAL_CONNECT = const(1)
_IRQ_CENTRAL_DISCONNECT = const(2)
_IRQ_GATTS_WRITE = const(3)

# 3. 蓝牙 UUID 定义（采用通用的 LED/Button 服务标准）
# 服务的 UUID: 00001523-1212-efde-1523-785feabcd123
_LED_SERVICE_UUID = bluetooth.UUID("00001523-1212-efde-1523-785feabcd123")
# 控制特性的 UUID (可写): 00001525-1212-efde-1523-785feabcd123
_LED_CHAR_UUID = (
    bluetooth.UUID("00001525-1212-efde-1523-785feabcd123"),
    bluetooth.FLAG_WRITE | bluetooth.FLAG_READ,
)
_LED_SERVICE = (_LED_SERVICE_UUID, (_LED_CHAR_UUID,),)

class BLE_LED_Controller:
    def __init__(self, name="AI_Glasses_BLE"):
        self._ble = bluetooth.BLE()
        self._ble.active(True)
        self._ble.irq(self._ble_irq)
        
        # 注册 GATT 服务
        ((self._handle,),) = self._ble.gatts_register_services((_LED_SERVICE,))
        
        # 初始化特性值（初始为 0x00，表示灭）
        self._ble.gatts_write(self._handle, bytes([0]))
        
        # 组装广播数据 (包含设备名称和公开的服务UUID)
        self._name = name
        self._payload = self._get_advertising_payload()
        self._advertise()
        print(f"BLE 设备已启动，正在广播名称: {self._name}")

    def _get_advertising_payload(self):
        # 构造标准的 BLE 广播数据包
        payload = bytearray()
        
        # 1. 广播 Flag
        payload.append(2) # 长度
        payload.append(0x01) # 类别: Flags
        payload.append(0x06) # 一般可发现模式 + 不支持 BR/EDR
        
        # 2. 广播名称
        name_bytes = self._name.encode('utf-8')
        payload.append(len(name_bytes) + 1)
        payload.append(0x09) # 类别: 完整设备名称
        payload.extend(name_bytes)
        
        return payload

    def _advertise(self):
        # 开始广播，每100ms广播一次
        self._ble.gap_advertise(250000, adv_data=self._payload)

    def _ble_irq(self, event, data):
        if event == _IRQ_CENTRAL_CONNECT:
            conn_handle, addr_type, addr = data
            # 转换 MAC 地址打印出来，确认手机确实连过来了
            mac = ":".join([f"{b:02x}" for b in addr])
            print(f"收到物理层连接连接! 句柄: {conn_handle}, 手机MAC: {mac}")
            
        elif event == _IRQ_CENTRAL_DISCONNECT:
            conn_handle, addr_type, addr = data
            print("连接断开或握手失败，重新开始广播...")
            self._advertise()
            
        elif event == _IRQ_GATTS_WRITE:
            conn_handle, value_handle = data
            if value_handle == self._handle:
                current_value = self._ble.gatts_read(self._handle)
                if current_value:
                    cmd = current_value[0]
                    if cmd in (1, 0x31):
                        led.value(1)
                        print("【BLE指令】点亮 LED")
                    elif cmd in (0, 0x30):
                        led.value(0)
                        print("【BLE指令】熄灭 LED")

# 启动蓝牙服务
ble_ctrl = BLE_LED_Controller()