Native Capacitive Touch - Arduino Nano

Using Arduino Sensors
1

Hi Everyone

I am playing around with the native capacitive touch function I found here: Arduino Playground - HomePage

I am using an arduino Nano with 8 analogue Inputs. For A6 and A7 the only reading I get is 17. The two pins appear to simply do nothing at all. I guess this might be an issue of the portmanipulation and bit-math which is going on in the function, but its really beyond my programming skills.

Does anyone know what the problem might be and how to fix it?

Thanks

p.

2

here is my code, though I doubt that is the issue:

void setup() {
  Serial.begin(9600);
}


void loop() {
  
  Serial.print(readCapacitivePin(A0));
  Serial.print(", ");
    Serial.print(readCapacitivePin(A1));
    Serial.print(", ");
    Serial.print(readCapacitivePin(A2));
   Serial.print(", ");
    Serial.print(readCapacitivePin(A3));
  Serial.print(", ");
    Serial.print(readCapacitivePin(A4));
  Serial.print(", ");
    Serial.print(readCapacitivePin(A5));
  Serial.print(", ");
    Serial.print(readCapacitivePin(A6));
  Serial.print(", ");
    Serial.print(readCapacitivePin(A7));
  Serial.println("");
  
  

  delay(1);        // delay in between reads for stability
}

The output on my serial console looks something like this:

2, 2, 1, 2, 2, 1, 17, 17
2, 2, 1, 2, 2, 1, 17, 17
2, 2, 1, 2, 2, 1, 17, 17
2, 2, 1, 2, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 2, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17
2, 2, 1, 1, 2, 1, 17, 17

If I touch a sensor, it looks like this:

2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 10, 2, 1, 17, 17
2, 2, 1, 8, 2, 1, 17, 17
2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 10, 2, 1, 17, 17
2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 6, 2, 1, 17, 17
2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 7, 2, 1, 17, 17
2, 2, 1, 9, 2, 1, 17, 17
2, 2, 1, 8, 2, 1, 17, 17
2, 2, 1, 7, 2, 1, 17, 17
3

pins A6 and A7 r no digital pins, IIRC...
they r just connected to the ADC MUX...

4

Brunsbuettel... wie schoen :smiley:

Yep - I was afraid of that. I didnt realize those two pins dont work that way until I had all my project soldered and cabled :-S .... if I had known in advance, I would have just used a mega. oh well...

5

u can use other pins?
or did u already use them all?

6

wait. they dont need to be analogue pins, do they ... maybe I can :smiley: facepalm

7

LOL XD