最近对Arduino很感兴趣，求Arduino电子琴程序讲解（最好详细一些，谢谢！）

int ledPin = 12;
int capval1;
int capval2;
int capval3;
int capval4;
int capval5;
int capval6;
int capval7;
int capval8;
void setup()
{
pinMode(ledPin, OUTPUT);

}

void loop ()
{
digitalWrite(ledPin,LOW);
capval1 = readCapacitivePin(3);
capval2 = readCapacitivePin(4);
capval3 = readCapacitivePin(5);
capval4 = readCapacitivePin(6);
capval5 = readCapacitivePin(7);
capval6 = readCapacitivePin(8);
capval7 = readCapacitivePin(9);
capval8 = readCapacitivePin(10);
if (capval1 > 2) {
tone(ledPin,262,10);
}
if (capval2 > 2) {
tone(ledPin,294,10);
}
if (capval3 > 2) {
tone(ledPin,330,10);
}
if (capval4 > 2) {
tone(ledPin,350,10);
}
if (capval5 > 2) {
tone(ledPin,393,10);
}
if (capval6 > 2) {
tone(ledPin,441,10);
}
if (capval7 > 2) {
tone(ledPin,495,10);
}
if (capval8 > 2) {
tone(ledPin,525,10);
}
}

uint8_t readCapacitivePin(int pinToMeasure) {
// Variables used to translate from Arduino to AVR pin naming
volatile uint8_t* port;
volatile uint8_t* ddr;
volatile uint8_t* pin;
// Here we translate the input pin number from
// Arduino pin number to the AVR PORT, PIN, DDR,
// and which bit of those registers we care about.
byte bitmask;
port = portOutputRegister(digitalPinToPort(pinToMeasure));
ddr = portModeRegister(digitalPinToPort(pinToMeasure));
bitmask = digitalPinToBitMask(pinToMeasure);
pin = portInputRegister(digitalPinToPort(pinToMeasure));
// Discharge the pin first by setting it low and output
*port &= ~(bitmask);
*ddr |= bitmask;
delay(1);
// Make the pin an input with the internal pull-up on
*ddr &= ~(bitmask);
*port |= bitmask;

// Now see how long the pin to get pulled up. This manual unrolling of the loop
// decreases the number of hardware cycles between each read of the pin,
// thus increasing sensitivity.
uint8_t cycles = 17;
if (*pin & bitmask) { cycles = 0;}
else if (*pin & bitmask) { cycles = 1;}
else if (*pin & bitmask) { cycles = 2;}
else if (*pin & bitmask) { cycles = 3;}
else if (*pin & bitmask) { cycles = 4;}
else if (*pin & bitmask) { cycles = 5;}
else if (*pin & bitmask) { cycles = 6;}
else if (*pin & bitmask) { cycles = 7;}
else if (*pin & bitmask) { cycles = 8;}
else if (*pin & bitmask) { cycles = 9;}
else if (*pin & bitmask) { cycles = 10;}
else if (*pin & bitmask) { cycles = 11;}
else if (*pin & bitmask) { cycles = 12;}
else if (*pin & bitmask) { cycles = 13;}
else if (*pin & bitmask) { cycles = 14;}
else if (*pin & bitmask) { cycles = 15;}
else if (*pin & bitmask) { cycles = 16;}

// Discharge the pin again by setting it low and output
// It's important to leave the pins low if you want to
// be able to touch more than 1 sensor at a time - if
// the sensor is left pulled high, when you touch
// two sensors, your body will transfer the charge between
// sensors.
*port &= ~(bitmask);
*ddr |= bitmask;

return cycles;
}

比如彩屏显示五颜六色的颜色 颜色参数就可以使用随机数字random（颜色值）。比如
setColor(random(255), random(255), random(255)); //红绿蓝的值都是在0~255范围随机调用