potmeter returns values 0, 1, 2 & 3 instead of 0 - 1023

Using Arduino Programming Questions
1

I connected a potmeter to my arduino like in this tutorial. https://www.arduino.cc/en/tutorial/potentiometer

But when printing the output to the monitor i get values of 0,1, 2 & 3 instead of a value between 0 and 1023.

Anybody got an idea why?

2

Post your code and circuit here

3

Circuit is like here https://www.arduino.cc/en/tutorial/potentiometer

#include <Wire.h>

int status_module = 0; 
#define potmeter A3

void setup() {
  Serial.begin(9600);
  Wire.begin(1);               
  Wire.onRequest(requestEvent); 
}

void loop() {
int pot_waarde = analogRead(potmeter); 
Serial.println (pot_waarde);
}

//SUB-ROUTINES
void requestEvent() { 
  Wire.write(status_module);
}
4

Let’s see your actual wiring.

.

5

Hi,
If you have the center terminal of the pot connected to A2.

Then

#define potmeter A3

should be.

#define potmeter A2

Tom... :slight_smile:

6

I found the problem. I had the potmeter hooked on the 5v and GND of another arduino (the master) and to pin A3 of the slave, where the sketch is running. I didn't think that would matter, but does... Anybody able to explain why?

7

Have you got the grounds of the two Arduinos connected together?

If not you won't get a proper reading.
You need to connect the two grounds together so that the second arduino has a zero volt reference to measure from.

If you were trying to measure the voltage with a multimeter, you wouldn't expect to get a correct reading with only the red probe connected, would you? That is in effect what you were trying to do.

8

If you would have replied to this "Let's see your actual wiring" as requested, we could have seen the problem. :wink:

9

justvervaart:
I found the problem. I had the potmeter hooked on the 5v and GND of another arduino (the master) and to pin A3 of the slave, where the sketch is running. I didn't think that would matter, but does... Anybody able to explain why?

WHAT OTHER ARDUINO? ? ? ?
There is only ONE Arduino in the link and diagram you referred too, saying;
[u]**I connected a potmeter to my arduino like in this tutorial. https://www.arduino.cc/en/tutorial/potentiometer**[/u]
No you didn't!
Why connect to another Arduino when the tutorial shows you don't?
Tom... :o

10