I have connected Arduino with ESP8266 with

Arduino pin 2 connected to ESP's Tx Arduino pin 3 connected to ESP's Rx via Voltage Divider Arduino GND connected to ESP's GND Arduino 3v3 connected to ESP's CH_PD

I have powered ESP8266 using 1117 Voltage regulator

When I initially bought ESP8266 it was working properly(I could even set up a server) but now when I connect it to Arduino an endless stream of garbage values is seen on the Serial Monitor...

The arduino is programmed with the following code

#include <SoftwareSerial.h>

SoftwareSerial esp8266(2,3); // make RX Arduino line is pin 2, make TX Arduino line is pin 3.
                             // This means that you need to connect the TX line from the esp to the Arduino's pin 2
                             // and the RX line from the esp to the Arduino's pin 3
void setup()
  esp8266.begin(9600); // your esp's baud rate might be different

void loop()
  if(esp8266.available()) // check if the esp is sending a message 
      // The esp has data so display its output to the serial window 
      char c = esp8266.read(); // read the next character.

    // the following delay is required because otherwise the arduino will read the first letter of the command but not the rest
    // In other words without the delay if you use AT+RST, for example, the Arduino will read the letter A send it, then read the rest and send it
    // but we want to send everything at the same time.

    String command="";

    while(Serial.available()) // read the command character by character
        // read one character
    esp8266.println(command); // send the read character to the esp8266
  • Maybe it helps if you tell us what happened between "initially" and "now"? Commented Jun 9, 2015 at 13:48
  • 1
    Lose the Arduino and program the ESP directly. You can do it with the same language as Arduino. github.com/esp8266/Arduino - also supported in UECIDE - all you need is a USB -> UART dongle.
    – Majenko
    Commented Jun 9, 2015 at 15:57
  • If the stream of garbage values comes in response to things you send to the ESP8266, then the problem is most likely the baud rate. For the ESP8266-01 modules that I have used, the default baud rate is 115200.
    – Kluge
    Commented Jun 11, 2015 at 22:59
  • I had already changed the Baud Rate of the Module to 9600 using AT+BAUD command..
    – AngryBird
    Commented Jun 12, 2015 at 3:44

1 Answer 1


There is a new command for the ESP8266 in AT version: - SDK version:1.4.0 that lets you explicitly set the full UART configuration:

AT+UART_CUR – set the current UART configuration This command sets the current UART configuration; it does not write to the flash. Hence there is no change in the default baud rate.

For example:


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