设置HC-05(ZS-040)至AT模式时Serial Monitor无输入响应

我按照相关教程步骤操作，已经在Serial Monitor中设置了NL & CR换行方式以及9600波特率，但仍然无法正常运行AT命令。

硬件配置 #

• Arduino MEGA 2560
• 蓝牙模块HC-05 (ZS-040)
• Ubuntu 16.04

接线方式 #

需说明：此前我曾多次未接电阻直接接线，但每次时长均不超过3-4分钟。

使用的代码 #

// Basic Bluetooth test sketch 5a for the Arduino Mega. // AT mode using button switch // HC-05 with EN pin and button switch //
// Uses serial with the host computer and serial1 for communication with the Bluetooth module //
// Pins // BT VCC to Arduino 5V out. Disconnect before running the sketch // BT GND to Arduino GND // BT RX (through a voltage divider) to Arduino TX1 (pin 18) // BT TX to Arduino RX1 (no need voltage divider) (pin 19) //
// When a command is entered in to the serial monitor on the computer // the Arduino will relay it to the Bluetooth module and display the result. //
char serialByte = '0';
const byte LEDPIN = 13;

void setup() {
  pinMode(LEDPIN, OUTPUT);
  // communication with the host computer
  Serial.begin(9600);
  Serial.println("Do not power the BT module");
  Serial.println(" ");
  Serial.println("On the BT module, press the button switch (keep pressed, and at the same time power the BT module");
  Serial.println("The LED on the BT module should now flash on/off every 2 seconds");
  Serial.println("Can now release the button switch on the BT module");
  Serial.println(" ");
  Serial.println("After entering AT mode, type 1 and hit send");
  Serial.println(" ");

  // wait for the user to type "1" in the serial monitor
  while (serialByte !='1') {
    if ( Serial1.available() ) {
      serialByte = Serial1.read();
    }
  }

  // communication with the BT module on serial1
  Serial1.begin(38400);
  // LED to show we have started the serial channels
  digitalWrite(LEDPIN, HIGH);
  Serial.println(" ");
  Serial.println("AT mode.");
  Serial.println("Remember to to set Both NL & CR in the serial monitor.");
  Serial.println("The HC-05 accepts commands in both upper case and lower case");
  Serial.println(" ");
}

void loop() {
  // listen for communication from the BT module and then write it to the serial monitor
  if ( Serial1.available() ) {
    Serial.write( Serial1.read() );
  }
  // listen for user input and send it to the HC-05
  if ( Serial.available() ) {
    Serial1.write( Serial.read() );
  }
}

问题细节 #

教程中说明：

蓝牙模块LED应变为每2秒闪烁一次（亮1秒、灭1秒），这表明已进入AT模式，此时可松开按键。

我的模块LED闪烁确实符合这个描述，但当我在Serial Monitor中输入“1”并发送后，没有任何响应。完成所有步骤后的Serial Monitor状态如下：

内容的提问来源于stack exchange，提问作者grrigore