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Orizzon
Asked: 2020-10-22 06:08:35 +0800 CST 2020-10-22 06:08:35 +0800 CST

Help with Arduino via Serial

  • 772

I have an Arduino that I use to move some servos. The Arduino has the following code:

#include<Servo.h>

//Creamos los objetos servo
Servo servo;
Servo servo2;
Servo servo3;
Servo servo4;

int enviado; //Aqui enviamos el numero completo
int num; //Numero del servo
int posicion; //Posicion del servo

void setup()
{
  //Inicializamos los Servos
  servo.attach(9);
  servo2.attach(10);
  servo3.attach(11);
  servo4.attach(6);

  //Inicializamos la comunicacion por Serial
  Serial.begin(9600);
}

void loop()
{
  if(Serial.available() >= 1)
  {
    /*
    1- Leer un numero entero por serial
    2- Calculamos su modulo por 10 (sera el numero del motor)
    3- Dividir el entero inicial por 10
    4- Lo que quede, sera la posicion del motor
    */
    enviado = Serial.parseInt();
    num = enviado%10;
    enviado = enviado/10;
    posicion = enviado;

    //Hora de mover los servos!
    if(num == 1)
    {
      servo.write(posicion);
    }
    else if(num == 2)
    {
      servo2.write(posicion);
    }
    else if(num == 3)
    {
      servo3.write(posicion);
    }
    else if(num == 4)
    {
      servo4.write(posicion);
    }
  }

}

The problem I have is that when I send the information necessary for the servo that I want to move to where I want, there is a delay between the time I press the button and the servo moves.

I don't know if the Arduino takes time to calculate what I command it to know what to do or if I'm doing something wrong.

arduino

1 Answers

  1. Best Answer

    The problem you are experiencing is because the function Serial.parseInt()waits for a delimiter character that ends the integer or waits for the maximum timeout set by default to 1 second in Serial.SetTimeout():

    Parsing stops when no characters have been read for a configurable time-out value, or a non-digit is read

    Which means that:

    Parsing ends when no characters have been read for a configurable time, or a non-digit character is read

    So when you type a number, the function waits for you to send something that ends the number (for example, a carriage return, a space, or any delimiter). Otherwise, it waits for 1000 ms until the input of the integer is finished.

    I recommend you to send a delimiter along with the number through the serial port. This way you will avoid the problem that you are suffering in this other question .

    • 2