Hello there! I want to use two arduino, each one is connected to a ultrasonic sensor and to a LCD screen (I2C). I want to show the read of sensor 1 in LCD 2 and show the read of sensor 2 in LCD 1 using serial communication. Both LCD show the right value the first time, but after that it starts showing wrong values and I don't know why. This is my script: #include #define trigPin 9 #define echoPin 8 int incomingByte = 0; Adafruit_LiquidCrystal lcd_1(0); #define trigPin 9 #define echoPin 8 void setup(){ lcd_1.begin(16, 2); Serial.begin(9600); pinMode(12, OUTPUT); pinMode(trigPin, OUTPUT); pinMode(echoPin, INPUT); } void loop(){ long sure, mesafe; // start of the sensor config digitalWrite(trigPin, LOW); delayMicroseconds(2); digitalWrite(trigPin, HIGH); delayMicroseconds(10); digitalWrite(trigPin, LOW); sure=pulseIn(echoPin, HIGH); // end od sensor config mesafe=(sure/2)/29.1; //value of sensor in cm Serial.print(mesafe, DEC); // printing value in serial delay(1000); if (Serial.available() > 0) { //checking for info incomingByte = Serial.read(); // saving value in variable Serial.print(incomingByte, DEC); digitalWrite(12, HIGH);//turning on a led if it's getting data } lcd_1.print(incomingByte, DEC); lcd_1.print(" cm"); delay(1000); lcd_1.clear(); digitalWrite(12, LOW); delay(1000); } [Tarea1]

Welcome! Sorry, I would like to help but I cannot read frizzy. Posting a real schematic with links to technical information on each of the hardware devices would help us help you. Even labeled hand drawn schematic is better. If you cannot draw you can download KiCad and use that. Many parts have the same name but are different. I am curious as to what displays you are using, apparently they have built in pull up resistors as I see none. I do not have a clue what the prototype board is there for, it is not being used other then splicing wires.

@juancarlossegovia You printing mesafe variable to serial as string, but reading it as single byte. It will not work. Please follow an advice in post #3

Arduino to arduino serial communication with sensor and LCD

Projects Programming

cattledog August 24, 2022, 1:52am 3

You would do well to review Serial Input Basics to see how to best frame and read serial messages.

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Arduino to arduino serial communication with sensor and LCD

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