(SOLVED!!!) Arduino Uno with ESP8266 not working over COM3

Projects Networking, Protocols, and Devices
1

Hi all.

I have googled the heck out of this but I can't seem to solve this issue.

I have connected the ESP8266 to Arduino as follow. (ESP8266 out of wrap)

10 => TX
11 => RX
V3.3 => VCC
GND => GND
V3.3 => CH_PD

see Image (Do note that the (RX, TX) pins in the Image are different)

Once I connect the Arduino via USB and while the ESP8266 is powered the IDE spits out an error:
"Board at COM3 is not available"
avrdude: ser_open(): Can't open device "\.\COM3" the system cannot find the file specified

I have tried uploading the code first and than plug in the ESP8266 but it will not work

I have the same issue on MAC and Windows.

To sum it up. The issue is when the ESP8266 is connected (CH_PD), the Serial Monitor cannot start. and i cannot communicate between arduino uno and the esp8266.

I have tried changing the pins of TX, RX but it does not seems to solve anything

#include <SoftwareSerial.h>

String ssid = "mynetwork";
String password = "password";

SoftwareSerial client(2,3);

void setup(){
    
    Serial.begin(9600);
    while(!Serial){
        //USB MODE ONLY
        
      }
      Serial.println("SERIAL CONNECTED");
    client.begin(9600);
    client.println("TEST WIFI CALLED");

  }


 void loop(){

  if (!client){
    client.begin(9600);
    client.println("NOT CONNECTED");
    }
  }

Thank you

download.jpg

2

see Image (Do note that the (RX, TX) pins in the Image are different)

There is no image.

And there is no code (use code tags!).

I have the same issue on MAC and Windows.

I doubt that the Mac will throw an error regarding COM3.

Once I connect the Arduino via USB and while the ESP8266 is powered the IDE spits out an error:

How is the ESP powered?

3

I updated my post with Code and image.

On the Mac there is no COM3 but dev/cu.usbmodem1421

I dont think the issue is with code. It has to do with either the connections or my ports
The ESP is powered by 3.3 directly from the Arduino

4

That code does nothing.

Post a bigger image, it's hard to get the connections correctly on a thumbnail image. I see the ESP connected to pins 0 and 1. Is that correct?

5

Correct

see bigger image.

When the ESP is connected and powered I cannot even upload the code to the Arduino.

its giving me the avrdude: ser_open(): cannot open device "\.\COM3": the system cannot find the file specified

connections.jpg
connections.jpg741×705 49.7 KB

6

When the ESP is connected and powered I cannot even upload the code to the Arduino.

Sure, your ESP blocks the UART interface that is used for upload.

As your software makes a SoftwareSerial connection on pins 2 and 3 why don't you use these pins? Or better, use pins 8 and 9 and change to the better AltSoftSerial library. SoftwareSerial is a crippled piece of software.

7

Issue Solved

When my Arduino Uno is connected via USB to computer the 3.3v pin only output 2.8v. The Wifi module did not get enough power.

Added 9v battery to power the Arduino