HC-05 AT Command not working

Using Arduino Programming Questions
#1

I have tried everything to get my HC-05 into AT Mode, I have looked up every way from using RX and TX pins to Digital Pins, nothing is working.

I have tried blank sketch to even get into AT Mode (Holding the button) and even tried adding HIGH to Pin 9 nothing is working

//RoboIndia Code for HC-05 with AT Mode
//https://www.roboindia.com/tutorials

#include <SoftwareSerial.h>

SoftwareSerial BTSerial(5, 6); // RX | TX

void setup()
{
  Serial.begin(9600);
  Serial.println("Enter AT commands:");
  BTSerial.begin(38400);       // HC-05 default speed in AT command more
}

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

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

there is one of the codes I have used, everything either turns up blank in Serial Monitor OR a bunch of backwards question marks, x’s and strange Boxes.

I have switched to 38400 and using both NL and CR.

Please help, not sure where to go as I have tried everything I could find as far as trouble shooting

#2

I have 3 pieces of HC-05. Old one (borrowed from my friend) works well and also responses to AT Commands.

The other two (Chinese clones) are anew; they work well with Bluetooth Master Terminal; but, they do not respond to AT commands.

The old one enters into AT Mode this way: press and hold the micro switch for about 2-sec; it enters into AT Mode.

For the anew two: power down; hold the micro switch; power up; release the micro switch after 2-sec. The HC-05 appears to have entered into AT Mode; but, it does not respond to AT Command.

#3

All HC-05s work the same way but the breakout boards on which they sit can vary and quite a few tutorials don’t reflect this. Two things can happen to spoil things.

  1. You are using a tutorial for a JY-MCU board but have a board with a switch
  2. You have an HC-06, not an HC-05
    Check here
    Arduino with HC-05 (ZS-040) Bluetooth module – AT MODE | Martyn Currey
    for the best and most comprehensive HC-05 config stuff
#4

Did you figure it out?

#5

Akeem:
Did you figure it out?

After two whole years have gone by, who are you asking?

#6

He probably didn't, and even he did, you will likely get better, and certainly more up-to-date guidance at the abovementioned Martyn Currey site.

#7