about Proteus Sub_circuit simulation

const int pwmPin = 12; // assigns pin 12 to variable pwm

const int potcyc = A0; // assigns analog pot input A0 to vary the cyc of pwm
const int potfre = A1; // assigns analog pot input A1 to vary the cfrequency of pwm


void setup()  // setup loop
{
  pinMode(pwmPin, OUTPUT);
  // Don't use pinMode() with analogRead()
}

void loop()
{
  float dutyCycleVal = analogRead(potcyc) / 1024.0;
  int delayVal = map(analogRead(potfre), 0, 1024, 2000, 0); // delay in

  digitalWrite(pwmPin, HIGH);
  delayMicroseconds(delayVal * dutyCycleVal); // The ON part of the cycle
  digitalWrite(pwmPin, LOW);
  delayMicroseconds(delayVal * (1.0 - dutyCycleVal));  // The OFF part of the cycle
}