Can't send data to ESP8266 via arduino - c

Question

I have an ESP8266-01 and I want to send sensor data from Arduino to ESP8266 via serial communication but the data I receive is not correct, I tried changing baud rates but no luck, here is the code
Code for ESP8266:
#include <SoftwareSerial.h>
void setup() {
// put your setup code here, to run once:
Serial.begin(38400);
}
void loop() {
// put your main code here, to run repeatedly:
while(Serial.available()) {
Serial.println("yes");
Serial.println(Serial.read());
}
delay(5);
}
Code for Arduino
#include <SoftwareSerial.h>
SoftwareSerial esp(1, 0);
String str;
void setup(){
Serial.begin(38400);
esp.begin(38400);
delay(2000);
}
void loop() {
// put your main code here, to run repeatedly:
str = String("Hi there");
esp.println(str);
esp.println("hi there");
delay(1000);
}
Here is the serial monitor:
Serial monitor showing numbers instead of "hi there"
The wiring connections are correct.

Answer 1

if you are using simple wires for the connection you might need to reduce the baud rate at 9600 or lower.
For higher speed you will need coaxial cables to get a decent communication distance. Moreover I am sure that you have checked the electrical connection obvously.
On the programming side, Serial.read() returns the first byte of incoming serial data available (or -1 if no data is available). Data type: int. This is why you are getting a single number instead of your string.
I would suggest to use Serial.readString() instead.
Please see the proper documentation here:
https://www.arduino.cc/reference/en/language/functions/communication/serial/
All the best