is that possible to setup one pin as a input and output

Projects Programming
1

in arduino uno is that possible to setup, one pin as a output and input sametime.
example void setup() {

pinMode(p1,INPUT);
pinMode(p1,OUTPUT);

}

2

I don't think there is anyway to do this. Even if there was, that way is probably incorrect.

4

ganesh07:
in arduino uno is that possible to setup, one pin as a output and input sametime.
example void setup() {

pinMode(p1,INPUT);
pinMode(p1,OUTPUT);

}

Only the last instruction will remain in effect, however both will execute. First, the compiler will link in the "input" code and then the compiler will link in the "output" code. When run, p1 will be an input for an instant and will flip over to an output pin ... Staying in output mode until changed.

You may find this discussion about four-value logic enlightening:

Ray

5

ganesh07:
in arduino uno is that possible to setup, one pin as a output and input sametime.
example void setup() {

pinMode(p1,INPUT);
pinMode(p1,OUTPUT);

}

Not like that, but there are ways to light an LED that reflects the input to a pin if that is what you want to do.

6

ganesh07:
in arduino uno is that possible to setup, one pin as a output and input sametime.
example void setup() {

pinMode(p1,INPUT);
pinMode(p1,OUTPUT);

}

Not at the SAME TIME. But you can switch back and forth between input and output as often as you like.

This is commonly done when sending and receiving serial data that goes on only one pin, for example:

    while (bits--) {
        digitalWrite (_SCK, LOW);
        pinMode (_DATA, OUTPUT);
        digitalWrite (_DATA, data & _BV (bits) ? HIGH : LOW);
        digitalWrite (_SCK, HIGH);
        pinMode (_DATA, INPUT_PULLUP);
        digitalRead (_DATA) ? data |= _BV (bits) : data &= ~_BV (bits);
    }
7

thanks guys. im doing a project for my school culminating, so i m tring to make a piezo sensor as a Knock Sensor and speaker

8

Well you can switch to an input to detect a knock and then change it over to an output to make a sound.