Keyestudio 4DOF Manual page 94

myservo2.attach(A0);
myservo3.attach(6);
myservo4.attach(9);
myservo1.write(pos1);
delay(1000);
myservo2.write(pos2);
myservo3.write(pos3);
myservo4.write(pos4);
delay(1500);
}
void loop()
{
// turn right
for(pos1;pos1>0;pos1--)
{
myservo1.write(pos1);
delay(5); // delay 5ms（used to adjust the servo speed）
}
delay(1000);
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