ESP8266 Community Forum

- Tue Apr 24, 2018 4:19 am #75573 I have a python server running on my PC and I am using an Arduino Uno (wifi enabled by a ESP8266 chip) as the client.I can make the the server and client communicate using AT commands as shown below:

Code: Select all SoftwareSerial esp (8,9);

       void setup()
       {
       esp.begin(9600);
       esp.println("AT+CWMODE=3");
       delay(100);
       esp.println("AT+CIPSTART=\"TCP\",\"192.168.8.100\",5555");
       delay(1000);
       esp.println("AT+CIPSEND=3");
       delay(100);
       esp.println("bbb");
       delay(100); }

The string "bbb" is recieved on the server and the server responds back, which is shown in the serial monitor as:

Code: Select all+IPD,19:the string is found

I want to read this response and use it back in the code for further conditional statements. But i am unable to do this. So far i have tried these methods.

1st method by using esp.readString() as shown below:

Code: Select allString buffer="";
    while (esp.available()>0)
        buffer+= esp.readString();   
    Serial.print(buffer);


2nd by using esp.read() as shown below:

Code: Select allString buffer="";
    char c;
    while (esp.available()>0) {
        c= esp.read();
        buffer+=c;}
    Serial.print(buffer);    // i have also tried using esp.write() directly for prinitng here intead of storing it in a buffer


These two methods returned with incomplete information in the response string buffer ie i only get:

Code: Select allbusy s...
   
    Recv 3 bytes
   
    SEND OK
   
    +IPD,19:the string


I can not get the entire response in the buffer as mentioned in the start i.e the string is/isnt found. On the other hand if i execute the command AT+CWLAP and store its response in the buffer string, i get the entire thing. So i cant understand why is there a difference storing these two response using the same technique.
Lastly i have also used esp.readBytes() as shown:

Code: Select allchar c[500];
    esp.readBytes(c,400);
    esp.write(c);


This code gives me the whole response sometimes but sometimes it just gives a long garbage value. But the times it does give me the complete +IPD response, it switches some of the alphabets ie `the string is found` becomes `the strjng is gound`
If anyone could help me out i'll be very thankful.