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Arduino
Arduino Forum Arduino led on and off program using hc05 bluetooth module doesn't work.
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Forum Thread Details
  • State Not Answered
  • Replies 3 replies
  • Subscribers 392 subscribers
  • Views 1193 views
  • Users 0 members are here
  • bluetooth
  • arduino uno
  • hc05
  • hc-05
  • arduino
Related

Arduino led on and off program using hc05 bluetooth module doesn't work.

Former Member
Former Member over 9 years ago

I have tried to connect my arduino with hc-05, and run a simple 'LED on and off' program. When I disconnected the rx and tx pins and tried sending the commands using serial monitor in arduino, and it worked perfectly alright. But when I connected the rx and tx pins of hc-05 bluetooth module, and used the Bluetooth terminal app from playstore to send and recieve commands, whatever I send doesn't get recieved the same, instead I get weird characters on my serial monitor. Someone please help me solve this. I have included the arduino code and the screen shots of the serial monitor and the app.

 

char junk;
String inputString="";

void setup()
{
Serial.begin(9600);
pinMode(13, OUTPUT);
}

void loop()
{
  if(Serial.available()){
  while(Serial.available())
  {
  char inChar = (char)Serial.read();
  inputString += inChar;
  }
  Serial.println(inputString);
  while (Serial.available() > 0) 
  { junk = Serial.read() ; }
  if(inputString == "a"){
  digitalWrite(13, HIGH); 
  }else if(inputString == "b"){ 
  digitalWrite(13, LOW);
  }
  inputString = "";
  }
}

 

Serial Monitor

Bluetooth terminal App

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  • clem57
    0 clem57 over 9 years ago

    Check if the terminal program in Arduino is using character return and line feed or not. If ob, turn off.

    Clem

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  • clem57
    0 clem57 over 9 years ago

    Check if the terminal program in Arduino is using character return and line feed or not. If ob, turn off.

    Clem

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