Only getting error from ESP8266 AT commands

Question

I am trying to get the ESP8266 work with Arduino AT commands. I am using the due. How do I get the ESP8266 to respond with anything other than ERROR?

Here is the current serial output:

AT
ERROR

Here is my code:

void setup() {
 Serial.begin(9600); 
 Serial3.begin(115200); //Manufacture said this is the correct baud rate 
}
void loop() {
 if ( Serial3.available() ) { Serial.write( Serial3.read() ); }
 if ( Serial.available() ) { Serial3.write( Serial.read() ); }
}

Here are my pin connections:

RX3 -> ESP TX
TX3 -> ESP RX
GND -> GND
3.3V -> CH_PD + VCC

• Juraj: do you have CR/LF set in Serial Monitor?
• gre_gor: Don't cross post. You also asked this on SO.
• Will Buxton: I didn't have CR/LF set. That fixed my problem

Answer 1

The AT firmware responded with ERROR because it received data, but timed out waiting for the CR/LF line ending.

AT commands must be terminated with Carriage Return '\r' and Line Feed '\n' control bytes/characters.