Controlling a servo
A servo is a small rotary motor. From a neutral (0) position it can rotate +90 and -90 degrees. You can connect things to the servo in order to make them move.
Parts
SG90 Micro-Servo
3 jumper wires
Wire the circuit
The servo has a connector to which you will connect three jumper wires. The connectors are for power, ground and signal. This chart shows how the wires on the servo connector map to GPIO pins:
Create the Xojo app
You'll use the open-source Xojo GPIO library to control the servo. This library has the GPIO.Servo module which contains methods you can call to easily set the servo positions. This code moves the servo to its neutral and the left (-90) and right (90) positions:
GPIO.SetupGPIO
Const kServoPin = 6 ' Change to the pin you used
Var servo As New GPIO.Servo(kServoPin)
If servo.ErrorCode = 0 Then
servo.Neutral
App.DoEvents(500)
servo.Left
App.DoEvents(500)
servo.Right
App.DoEvents(500)
servo.Cleanup
End If
Transfer the built app to the Pi to test it out.