Keyestudio 4DOF Manual page 215

delay(5);
if(pos2<0)
{
pos2=0;
}
}
// the upper arm will go down
void RB()
{
pos2=pos2+1;
myservo2.write(pos2);
delay(5);
if(pos2>180)
{
pos2=180;
}
}
//***************************************
// the lower arm will stretch out
void LB()
{
pos3=pos3+1;
myservo3.write(pos3);
delay(5);
if(pos3>180)
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