ESP8266 Community Forum

- Sat Jul 09, 2016 7:07 am #50443 Hello, I connected ESP 01 to Arduino UNO and I would like to send AT commands to ESP. I use Arduino IDE.
On my ESP01, I used folowing pins:

ESP01:
Vcc -> 3,3V
Gnd -> Gnd
Rx -> Arduino Tx(pin 1), I used voltage divider of 2 resistors to make it 3,3V
Tx -> Directly to Arduino Rx(pin 0)
CH_PD -> 3,3V


After I turn on ESP01, I receive message "ready", but when I try to send AT command to ESP, it only puts random characters to serial monitor. If I try to send multiple commands, they are inserted directly next to previous characters (no new line). I use setting "Both NL & CR" and 115200 baud, tested also with 9600 baud and then every character is damaged.

See screnshot below:

- Sun Jul 10, 2016 11:26 am #50504 Hello,

Do you have a power supply for the ESP8266?

I recommend use a 3,3V source when working with the ESP8266. Rememeber connect both GND.

I have worked with that circuit and I have used the 2 and 3 arduino's pins. Of course you must change it in the sketch.

- Mon Jul 11, 2016 11:58 am #50584 Yes, I used both 3,3V power supply from arduino and also 3,3V/1A external power source, interconnected both GNDs as you suggested and still no sucess.

Voltage divider that I use are two resistors 3300Ohm and 6600Ohm, not sure if values arent so high. Not sure if that could be problem possibly.

Thing is also that I sometimes get message "ready" and sometimes not (only random characters). Have no idea why

- Mon Jul 11, 2016 2:18 pm #50590 Thank you for your post, I already solved this problem. My arduino is connected to PC via usb, so I changed pins for communication with ESP by SoftwareSerial to pins 10 and 11. Now it works.