Keyestudio 4DOF Manual page 22

//80 Degree Code:
// servopulse(servopin,80);
//180 Degree Code:
// servopulse(servopin,180);
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Notice:
Set well the servo angle and complete the below servo
base plate assembly, power off the servo to avoid the
angle error and make sure the servo can rotate freely.
Don't over-tighen the screws.
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