I used the code below to control an ESP8266. I am getting some unknown symbols in the responses.

#include <SoftwareSerial.h>
const byte rxPin=2;
const byte txPin=3;
SoftwareSerial ESP8266( rxPin, txPin);

void setup() {
  // put your setup code here, to run once:


void loop() {
  Serial.println("sending an AT command");

    String inData = ESP8266.readStringUntil('\n');
    Serial.println("Got Response:" + inData);
  // put your main code here, to run repeatedly:


The unknown symbols are shown in the screen shot.

unknown symbols

What might the problem be?

  • I have included software serial library – Aishwarya k Nov 4 '16 at 15:30
  • Did you try changing the baud rate on software serial? – gre_gor Nov 4 '16 at 15:34
  • Unfortunately your image has been shrunk so much that I can't make out what it says. – sa_leinad Nov 4 '16 at 15:40
  • I tried using 57600 baud rate – Aishwarya k Nov 4 '16 at 15:54
  • Even changed the serial monitor setting below to carriage return also – Aishwarya k Nov 4 '16 at 15:55

I nutted over this for quite a while. If you look up the reference for SoftwareSerial - https://www.arduino.cc/en/Reference/SoftwareSerial - and look at the limitations, you'll find that it won't work above 57k baud rate and pins 2 and 3 wont support change interrupts, whatever they are. Sometimes I think some of these projects are untested. I think I'll use the hardware ports on two arduinos and use SoftwareSerial on the right pins and baud rate to get the two arduinos to communicate, or use Software serial to talk to the pc through a MAX232. I don't think you'll get a 115200 baud esp to talk SoftwareSerial

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