|first project| Making a CapSense "Piano" with vegetables

I’m making a simple capacitive sensor piano with fruits and vegetables for input, pretty much this: Arduino + Capsense + Fruit - YouTube

#include <CapacitiveSensor.h>
#define SND_PIN 12 
int range = 300; 
byte button; 
int freq; 

/*
 * CapitiveSense Library Demo Sketch
 * Paul Badger 2008
 * Uses a high value resistor e.g. 10 megohm between send pin and receive pin
 * Resistor effects sensitivity, experiment with values, 50 kilohm - 50 megohm. Larger resistor values yield larger sensor values.
 * Receive pin is the sensor pin - try different amounts of foil/metal on this pin
 * Best results are obtained if sensor foil and wire is covered with an insulator such as paper or plastic sheet
 */


CapacitiveSensor   cs_4_2 = CapacitiveSensor(4,2);        // 11 megohm resistor between pins 4 & 2, pin 2 is sensor pin, add wire, foil
CapacitiveSensor   cs_4_5 = CapacitiveSensor(4,5);        // 11 megohm resistor between pins 4 & 6, pin 6 is sensor pin, add wire, foil
CapacitiveSensor   cs_4_8 = CapacitiveSensor(4,8);        // 11 megohm resistor between pins 4 & 8, pin 8 is sensor pin, add wire, foil


void setup()                    
{

  
   Serial.begin(9600);

}

void loop()                    
{
   
    long total1 =  cs_4_2.capacitiveSensor(30);
    long total2 =  cs_4_5.capacitiveSensor(30);
    long total3 =  cs_4_8.capacitiveSensor(30);
      button = 0;
  if (total1 > range) button |= 1;
  if (total2 > range) button |= 2;
  if (total3 > range) button |= 4;
  switch (button) {
   case 1: freq = 500; break;
   case 2: freq = 300; break;
   case 3: freq = 400; break;
   case 4: freq = 500; break;
   case 5: freq = 600; break;
   case 6: freq = 700; break;
   case 7: freq = 800; break;
   default: freq = 0;
  }


    Serial.print("\t");                    // tab character for debug window spacing

    Serial.print(total1);                  // print sensor output 1
    Serial.print("\t");
    Serial.print(total2);                  // print sensor output 2
    Serial.print("\t");
    Serial.println(total3);                // print sensor output 3

   freq? tone(SND_PIN, freq) : noTone(SND_PIN);
   delay(200);

And it seems to be working,well, halfway.
The speaker gives a tone with a 2-3 second delay, and keeps the tone going for about just as long.
I need immediate response and tone that last a limited time, like 500 ms. A quick beep-boop. The problems seems to be with the code - the signal from the board seems to be received with fixed interval of about 2 seconds, or every time it checks COM port i.e it only beeps when serial printer says the value is above threshold, but it only checks for the value every two seconds or so. Can I can change sensor-to-board data exchange rate? I’m an absolute beginner, pardon my greenness.

Any help or advice would be greatly appreciated. Diagram is in the attachment.

EDIT:
I’m thinking it’s the loop speed, I get a capacitance reading only every 2 seconds or so. I’ve removed all delays, have no millis () or anything like that. so all code repeat infinitely and “very fast”, but I get a reading every 1.5 seconds or so.

Could it be hardware lag?

I've removed all delays,

What is this then?

freq? tone(SND_PIN, freq) : noTone(SND_PIN);
   delay(200);

What is causing the sound?

but it only checks for the value every two seconds or so.

What in this sentence is it?

he speaker gives a tone with a 2-3 second delay, and keeps the tone going for about just as long.

You should not connect a speaker direct to an Arduino pin, you will damage the pin by drawing too much current from it. You need a 120R resistor in series with the speaker.

Solved it.

If you have your code checking for capacitance of three pin pairs, but have less than three pairs connected you'll get lag (about 1600 millis of it), arduino gets stuck trying to get the reading.

Cheers.

OK, that lack of hardware would have been good to know in the origional post. Hard to guess that one. ;)