#include<Servo.h>
Servo servo12;
Servo servo34;

#define servoPin12 6
#define servoPin34 7

int pos = 180 ;
int i = 0;
void setup() {
  // put your setup code here, to run once:
  servo12.attach(servoPin12);
  servo34.attach(servoPin34);
  servo12.write(0);
  servo34.write(0);
  Serial.begin(9600);
}

void loop() {
  // put your main code here, to run repeatedly:
  Serial.println("enter command :");
  while (Serial.available() == 0) {}
  int cmd = Serial.parseInt();
  if (cmd == 12)
  {
    motor12close();
  }
  if (cmd == 21)
  {
    motor12open();
  }
  if (cmd == 34)
  {
    motor34close();
  }
  if (cmd == 43)
  {
    motor34open();
  }
}

void motor12close()
{
  for (i = 0; i <= pos; i++)
  {
    servo12.write(i);
    delay(10);
  }
}
void motor12open()
{
  for ( i = pos; i >= 0; i--)
  {
    servo12.write(i);
    delay(10);
  }
}

void motor34close()
{
  for (i = 0; i <= pos; i++)
  {
    servo34.write(i);
    delay(10);
  }
}
void motor34open()
{
  for ( i = pos; i >= 0; i--)
  {
    servo34.write(i);
    delay(10);
  }
}