Trouble connecting Esp8266 to arduino UNO

Hi There,

Im trying to hook up my newly acquired esp8266 WIFI module to a arduino UNO board.

I searched the web for how to do this and the easiest solution was to connect it directly to the arduino boards 3.3v pin.

So this is my setup (or at least i think it is). If you spot mistakes in the pictures I upload please let me know :slight_smile:

arduino - esp8266
RX ----- RX
TX ----- TX
GND — GND
3.3V — VCC
3.3V — CH_PD

I also added LiquidCrystal_I2C screen to display debug data.

My problem is that i don’t get any response, when I send commands to the module - I always get a timeout. The esp-module appears to be turned on (indicated by the red light) and a blue light flickers when i upload new code.

I attached my ino code and a couple of pictures of the wiring. Im brand new to electronics so dont assume i know anything.

I found this page from googling and want to try the two gotchas: http://nerdclub-uk.blogspot.dk/2014/10/getting-esp8266-wifi-module-to-work.html
But im not sure I understand what to do.

“Gotcha number 1; use a dedicated power supply (3.3.v)”
So here i tried connecting the 9v battery from my arduino starter pack to my arduino UNO . I assume that is sufficient?

“Gotcha number 2: pull the RESET + CH_PID lines high, but not the GPIO lines.”
This is what i did in practise:

  • disconnected the power from the arduino board.
  • moved the orange wire next to the red wire
  • connected the power for a few seconds.

Basicly i don’t understand the term “pull the line high”. Any elaboration on this matter what be much appreciated.

Things I’ve tried:

  • Sending reset command to the esp: “AT+RST” - still no response
  • Changing the baud rate (9600, 115200, 57600).

Question summary:

  • Why am I not getting a response from esp?
  • How do I reset the esp manually (wiring)

Any help / pointers / comments would be much appreciated :slight_smile:

Thx in advance

Best regards
Jonas



TestCommands.ino (1.31 KB)

I searched the web for how to do this and the easiest solution was to connect it directly to the arduino boards 3.3v pin.

This is most likely your first problem. The ESP8266 can draw to much current for the Arduino 3.3V pin to supply. Get a separate 3.3V power supply like this for testing.
Also your not level shifting the arduino TX down to 3.3V and this may cause problems (some people say it works okay at 5V but is it worth the risk?)

If think that:

arduino - esp8266
RX ----- RX
TX ----- TX
GND --- GND
3.3V --- VCC
3.3V --- CH_PD

Should be:

arduino - esp8266
RX ----- TX
TX ----- RX
GND --- GND
3.3V --- VCC
3.3V --- CH_PD