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Please be gentle with me. I am attempting to modify the configurations of my HC-05 bluetooth module by using the AT command set. The method by which I'm trying to do this is by implementing the following connection:

HC-05 GND --> Arduino GND; HC-05 3.3v --> Arduino 3.3V; HC-05 TX --> Arduino Pin 10; HC-05 RX --> Arduino Pin 11; HC-05 KEY --> Arduino Pin 9

enter image description here

This is the code which I uploaded to my Arduino (btw my arduino uno is an SMD clone): (code's from http://www.instructables.com/id/Modify-The-HC-05-Bluetooth-Module-Defaults-Using-A/step2/The-Arduino-Code-for-HC-05-Command-Mode/)

#include <SoftwareSerial.h>

SoftwareSerial BTSerial(10, 11); // RX | TX


void setup() {
  pinMode(9, OUTPUT);  // this pin will pull the HC-05 pin 34 (key pin) HIGH to switch module to AT mode
  digitalWrite(9, HIGH);
  Serial.begin(9600);
  Serial.println("Enter AT commands:");
  BTSerial.begin(38400);  // HC-05 default speed in AT command more

 }

void loop() {
  // Keep reading from HC-05 and send to Arduino Serial Monitor
  if (BTSerial.available())
    Serial.write(BTSerial.read());

  // Keep reading from Arduino Serial Monitor and send to HC-05
  if (Serial.available())
    BTSerial.write(Serial.read());

}

The problem is I can't seem to activate the AT mode. I don't get any response from the Serial Monitor whatever AT command I try. I double-checked the wiring and it's all good. I can't figure out what the problem is.

Thomas S.
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DorkOrc
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2 Answers2

1

After 3 hours I magically solved my pretty simple problem myself. If you wired the HC-05 and arduino correctly, the module should indicate that it's in AT Mode by blinking the LED in an interval of 2 seconds. You should get response in the Serial Monitor by typing the AT commands by switching from "No line ending" to "Both NL and CR". That's about it.

DorkOrc
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-1

In setup() put pin 9 to low, and delay it for about 1 second and then put it to high.

gre_gor
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safa
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