title: ESP8266 serial returning 'garbage' to Arduino
body: <p>I bought ESP8266 module and I connected to Arduino UNO board through SoftwareSerial (PIN 10 - RX, PIN 11 - TX), 
  I have also expternal power suply for ESP8266 5V (450mA) it reduced to 3.3V by step-down converter.</p>
  
  <p>Connections:</p>
  
  <p>ESP 8266</p>
  
  <p>Vcc - 3.3V from external powers suply</p>
  
  <p>CH_PD - 3.3V from external powers suply</p>
  
  <p>GND - GND from external</p>
  
  <p>RESET - not connected</p>
  
  <p>GPIO - not connected</p>
  
  <p>GPI2 - not connected</p>
  
  <p>RX &lt;- 5V from Arduino reduced to 3.3V by 3x10K ohm resistors</p>
  
  <p>TX -> 3.3 to arduino</p>
  
  <p><a href="https://i.stack.imgur.com/xzsx9.jpg" rel="nofollow noreferrer">Electrical connections</a></p>
  
  <p>and I upload to Arduino sample program to test esp8266 communication.</p>
  
  <p>Arduino program:</p>
  
  <pre><code>#include &lt;SoftwareSerial.h&gt;
  
  const byte rxPin = 10; // Wire this to Tx Pin of ESP8266
  const byte txPin = 11; // Wire this to Rx Pin of ESP8266
  
  // We'll use a software serial interface to connect to ESP8266
  SoftwareSerial ESP8266 (rxPin, txPin);
  
  void setup() {
    Serial.begin(9600);
    ESP8266.begin(9600); // Change this to the baudrate used by ESP8266
    delay(1000); // Let the module self-initialize
  }
  
  void loop() {
  
    delay(100);
  
    Serial.println("Sending an AT command...");
    ESP8266.println("AT\r\n");
    delay(30);
    while (ESP8266.available()){
       String inData = ESP8266.readStringUntil('\n');
       Serial.println("Got reponse from ESP8266: " + inData);
    }  
  }
  </code></pre>
  
  <p>but i not working corectly... When Arduino send message to ESP. ESP returns only rubish.. withot "Ready" and don't get firmware information. I tested all speed baud it look's the same...</p>
  
  <p><a href="https://i.stack.imgur.com/LORUj.png" rel="nofollow noreferrer">Serial monitor - printscreen</a></p>
  
  <p>When I manually send "AT" command from serial monitor EPS don't response anything!</p>