Keyestudio 4DOF Manual page 97

// Lower the arm
for(pos3;pos3>50;pos3--)
{
myservo3.write(pos3);
delay(5);
}
delay(1000);
// open the claw
for(pos4;pos4<100;pos4++)
{
myservo4.write(pos4);
}
delay(1000);
// lift up the arm
for(pos3;pos3<120;pos3++)
{
myservo3.write(pos3);
delay(5);
}
delay(1000);
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