I am using serial communications using arduino uno and esp8-01 ai thinker , I dont know whats best baud rate for them. Im using:
Serial.begin(115200);
esp8266.begin(115200);
but I got this unreadable symbols in my serial monitor :
AT+CWMO"⸮OF⸮D⸮D⸮e⸮L⸮
and it wasnt plain readable text. How can I fix this ? Thanks for help.
I dont know whats best baud rate for them.
Fast and the same, what you are using looks fine.
but I got this unreadable symbols in my serial monitor
How do the other AT commands respond? How have you wired it up? Do you have a common ground between the two processors?
How do you have the ESP-01 connected to the Uno?
Did you select appropriate baud rate in serial monitor?
Emsy23:
I am using serial communications using arduino uno and esp8-01 ai thinker , I dont know whats best baud rate for them. Im using:Serial.begin(115200);
esp8266.begin(115200);
That suggests to me that you are using an instance of SoftwareSerial called esp8266 to communicate with your ESP8266 and SoftwareSerial will not work at 115200 baud. 38400 is probably the max and 9600 would be a good starting point.
The baud rate used to communicate between the Arduino and the ESP8266 must be the same at both ends. But it does not have to be the same as the baud rate used by the Arduino to communicate with the Serial Monitor.
...R
PS ... always post your complete program to avoid confusion
Show both code and a picture of the circuit if you don't mind.
Why would you need to send data that fast? Serial.begin(9600); never failed me.
Plus, I highly recommend changing the title to "Serial problems with Arduino Uno and esp8-01 ai thinker"
Robin2 is right, the problem is that 115200 baud is too fast for SoftwareSerial. Use a lower baud rate.
Pieter
#include <SoftwareSerial.h>
#define DEBUG true
SoftwareSerial esp8266(2,3); // ESP RX PIN SA ARDUINO PIN 3, ESP TX SA ARDUINO PIN 2
void setup()
{
Serial.begin(115200);
esp8266.begin(115200); // your esp's baud rate might be different
sendData("AT+RST\r\n",2000,DEBUG); // reset module
sendData("AT+CWMODE=2\r\n",1000,DEBUG); // configure as access point
sendData("AT+CIFSR\r\n",1000,DEBUG); // get ip address
sendData("AT+CIPMUX=1\r\n",1000,DEBUG); // configure for multiple connections
sendData("AT+CIPSERVER=1,80\r\n",1000,DEBUG); // turn on server on port 80
}
void loop()
{
if(esp8266.available()) // check if the esp is sending a message
{
while(esp8266.available())
{
// The esp has data so display its output to the serial window
char c = esp8266.read(); // read the next character.
Serial.write(c);
}
if(esp8266.find("+IPD,"))
{
delay(1000);
int connectionId = esp8266.read()-48; // subtract 48 because the read() function returns
// the ASCII decimal value and 0 (the first decimal number) starts at 48
String webpage = "
String cipSend = "AT+CIPSEND=";
cipSend += connectionId;
cipSend += ",";
cipSend +=webpage.length();
cipSend +="\r\n";
sendData(cipSend,1000,DEBUG);
sendData(webpage,1000,DEBUG);
webpage="LED2";
cipSend = "AT+CIPSEND=";
cipSend += connectionId;
cipSend += ",";
cipSend +=webpage.length();
cipSend +="\r\n";
sendData(cipSend,1000,DEBUG);
sendData(webpage,1000,DEBUG);
String closeCommand = "AT+CIPCLOSE=";
closeCommand+=connectionId; // append connection id
closeCommand+="\r\n";
sendData(closeCommand,3000,DEBUG);
}
}
}
String sendData(String command, const int timeout, boolean debug)
{
String response = "";
esp8266.print(command); // send the read character to the esp8266
long int time = millis();
while( (time+timeout) > millis())
{
while(esp8266.available())
{
// The esp has data so display its output to the serial window
char c = esp8266.read(); // read the next character.
response+=c;
}
}
if(debug)
{
Serial.print(response);
}
return response;
}
// This is my sample code. I use Esp-01 adapter to connect my esp to arduino
You have already received the solution in Reply #4
To make it easy for people to help you please modify your post and use the code button </> so your code looks like this and is easy to copy to a text editor. See How to use the Forum
...R