simple Hbridge and PWM example

//this is my example for demonstration H-bridge on n-p-n transistors (BJT - Bipolar Junction Transistors) and for PWM
//simpleGo function is for H-bridge presentation
//PWMmotor - simple PWM example
//this code placed on Pastebin
uint8_t pwm = 55;
uint8_t step = 1;
void setup() {
  pinMode(6, OUTPUT);
  pinMode(3, OUTPUT);
  Serial.begin(9600);
}

void simpleGo(){
  digitalWrite(6, 1);
  digitalWrite(3, 0);
  delay(2000);
  digitalWrite(6, 0);
  digitalWrite(3, 0);
  delay(2000);
  digitalWrite(6, 0);
  digitalWrite(3, 1);
  delay(2000);
  digitalWrite(6, 0);
  digitalWrite(3, 0);
  delay(2000);
}
void PWMmotor(){
while(pwm<=254) {
    analogWrite(6, pwm);
    delay(100);
    pwm  = pwm + step;
    Serial.print("INCREASE");
    Serial.println(pwm);
}

while(pwm>=55) {
    analogWrite(6, pwm);
    delay(100);
    pwm  = pwm - step;
    Serial.print("decrease decrease decresase");
    Serial.println(pwm);
}

}

void loop() {
//simpleGo();
//PWMmotor();
analogWrite(6,120);
}