Arduino蓝牙模块连接下降

Question

我正在使用一个HC_05蓝牙模块和一个Arduino Uno试图建立一个简单的蓝牙连接我的Windows (HTC8X)。我是跟随在线教程这里。

当我进入设置时，我的手机会看到"HC_05“蓝牙信号。我点击它，它马上就连接起来了。它保持连接5-10秒，然后突然断开连接.

我认为我的手机没有接收到来自蓝牙模块的任何数据，因此决定信号是毫无价值的，并丢弃它。但即便如此，为什么呢？当我从链接代码调用btSerial.read()时，这不是在和设备说话吗？

“Arduino法典”：

#include <SoftwareSerial.h>

const int TX_BT = 10;
const int RX_BT = 11;

SoftwareSerial btSerial(TX_BT, RX_BT);

//Frequency to send periodic messages to Windows Phone, in milliseconds.
//Core code.
const unsigned long periodicMessageFrequency = 5000;
unsigned long time = 0;

//Process the incoming command from Windows Phone.
//It should be changed according to what you want to do.
void processCommand(char* command) {
}

//Send a message back to the Windows Phone.
//Is can't be changed.
void sendMessage(char* message) {
  int messageLen = strlen(message);
  if(messageLen < 256) {  
    btSerial.write(messageLen);
    btSerial.print(message);
  }
}

//Send a set of periodic messages to the Windows Phone.
//It should be changed according to what you want to do.
//This message could be a sensor data, like a thermometer data.
void sendPeriodicMessages() {
}

//Setup Arduino function
void setup() {
  Serial.begin(9600);
  Serial.println("USB Connected");
  btSerial.begin(9600);
}

//Loop Arduino function
//It can't be changed
void loop() {
  if(btSerial.available()) {
      int commandSize = (int)btSerial.read();
      char command[commandSize];
      int commandPos = 0;
      while(commandPos < commandSize) {
        if(btSerial.available()) {
          command[commandPos] = (char)btSerial.read();
          commandPos++;
        }
      }
      command[commandPos] = 0;
      processCommand(command);
  }
  unsigned long currentTime = millis();
  if((currentTime - time) > periodicMessageFrequency) {
    sendPeriodicMessages();
    time = currentTime;
  }
}

HC_05按以下方式连接：

GND -> GND
3.3V -> 3.3V
RX -> D11
TX-> D10

Answer 1

您将HC-05与Arduino直接连接到Tx线路.HC-05应该在3.3v而不是5伏的情况下驱动。您的Arduino Tx引脚将在HC-05的Rx线路上提供5v信号，高于重新推荐的水平。尝试在Arduino Tx引脚(5v)和HC-05 Rx引脚(3.3V)之间放置一个电压转换器。

也许内部有一个保护，当电压超过3.3时，可以重置HC-05内部的微控制器。