Please can anyone help me why I receive this symbols

[hell-o]

You will find my code and the strange symbol.
Please if you have any suggestion tell me.

Thank you in advance.

[anon73444976]

Because software serial doesn't work very well at 115200bps?

Please remember to use code tags when posting code

[Koepel]

Did the ESP32 have two-and-a-half serial port ? Try a hardware serial port.

Maybe the sketch is correct and that code is indeed received ?

Do you know that if the mySerial.readString() function times out, does it return a valid string ? I don't know, that's why I don't use that function.

You don't need the String object:

if( mySerial.available() > 0)
{
  int inChar = mySerial.read();
  Serial.write( (byte) inChar);
}

[rohitbd]

Is this garbled text random or consistent? If random then it could be a physical connection or wiring issue. If wiring is good then try a slower baud setting and the handshaking scheme - on windows, I believe the default is "None" - try changing that and see if it helps.

[david_2018]

As previously stated, softwareserial is known to be unreliable to completely unusable at higher baud rates. Softwareserial uses interrupts, and another interrupt occurring in mid-character can cause incorrect results.

[oqibidipo]

@Koepel

Did the ESP32 have two-and-a-half serial port ? Try a hardware serial port.

Don't let the sketch name fool you, it is running on an Uno.

[hell-o]

Thank you very much for your suggestion you are right I change the baud rate from 115200 to 9600 and everything works perfectly.

[hell-o]

Hi, everyone I like to thank you for all your suggestions. The real problem was the baud rate 115200.