ESP8266 Community Forum

- Tue Dec 02, 2014 9:29 am #3819 Hi all,
Last week I have bought one of these interesting devices in the hope of being able to connect my Arduino Uno via WIFI to my network. After several hours of testing, and after having exhausted all the possible solutions I had found here and in other sites I am still unable to get something meaningful from it.
So I hope someone will be able to give me some suggestions.
This is the connection:

Arduino ESP8266
Pin10 TX
Pin11 RX
GND GND
3.3V VCC
3.3V CH_PD
(I have also tried connecting GPIO1 and Reset to 3.3V but that did not change anything)

When I fire up Arduino the red light and the blue light on the ESP8266 turn on and stay on. Is it correct that blue light remains on?
I have then tried to use this code (from paranoja):

#include <SoftwareSerial.h>
SoftwareSerial esp(10,11); //ESP firmware has to be 0018000902 so the baudrate can be set to 9600
String str; //serial input&output
String stresp; //ESP input& output

void setup()
{
Serial.begin(9600);
esp.begin(9600);
}

void loop()
{
Serial.println("unesi komandu/fire the AT command");
delay(100);
while(Serial.available() == 0){}
str=Serial.readString();
esp.println(str);
while(esp.available() == 0){}
stresp=esp.readString();
Serial.println(stresp);
}

And when I opened the Serial Monitor I have started seeing a continuous stream of garbage that went on for quite some time, before I decided to terminate it. I have tried changing the Baud rate from 9600 all the way up to 115200, but it just changed the way this garbage data looked. (I have also tried the alternate version someone suggested in paranoja's post, but to no avail).
Next I tried adding a voltage divider to the RX side, as suggested by someone on this forum but it did not help.
Finally I have tried the same connection as above, but connecting Arduino TX to ESP8266 RX and Arduino RX to ESP8266 TX and then after having loaded the BareMinumum sketch I have tried issuing AT commands through the Serial Monitor, but in this case nothing came back, not even garbage data .
I have noticed that if CH_PD is not connected the blue light is off and when issuing a command it comes briefly on, but also in this case nothing comes back from the device.
Since I don’t have a USB to TTL converter yet, is there a way to see at what speed the ESP8266 is set by default?

Is it possible the board is fried?

All suggestions are very welcome!

Nodduino

P.S. Sorry for the long post!

- Tue Dec 02, 2014 9:59 am #3822

Finally I have tried the same connection as above, but connecting Arduino TX to ESP8266 RX and Arduino RX to ESP8266 TX and then after having loaded the BareMinumum sketch I have tried issuing AT commands through the Serial Monitor, but in this case nothing came back, not even garbage data .

if you are trying to make use of your arduino's usb to serial, ESP tx should be connected to Arduino tx. and ESP rx to arduino rx.
arduino rx is connected to usb to serial tx. and arduino tx is to usb to serial rx.

- Tue Dec 02, 2014 10:31 am #3824

Finally I have tried the same connection as above, but connecting Arduino TX to ESP8266 RX and Arduino RX to ESP8266 TX and then after having loaded the BareMinumum sketch I have tried issuing AT commands through the Serial Monitor, but in this case nothing came back, not even garbage data .

if you are trying to make use of your arduino's usb to serial, ESP tx should be connected to Arduino tx. and ESP rx to arduino rx.
arduino rx is connected to usb to serial tx. and arduino tx is to usb to serial rx.

I did not know that. I'll try with that configuration and the BareMinimum sketch. Do you think I need to have the voltage divider too on the RX side?

- Tue Dec 02, 2014 10:35 am #3825 for some reason, i dont use the voltage divider.
but maybe it is better to have it with your set up.