5.5 Use Internal Library

In the Arduino IDE, you can use many built-in libraries by adding the corresponding .h file directly to your code.

This project uses the Servo library to drive the Servo, so that it can rotate between 0° and 180°.

Required Components

In this project, we need the following components.

It’s definitely convenient to buy a whole kit, here’s the link:

Name

ITEMS IN THIS KIT

LINK

3 in 1 Starter Kit

380+

3 in 1 Starter Kit

You can also buy them separately from the links below.

COMPONENT INTRODUCTION

PURCHASE LINK

SunFounder R3 Board

BUY

Jumper Wires

BUY

Servo

BUY

Schematic

../_images/circuit_6.2_servo.png

In this project, we use PWM pin 9 to drive the Servo, and get the orange wire of the servo connected to the PWM pin 9, the red one to 5V, and the brown one to GND.

Wiring

../_images/swinging_servo_bb.jpg

Code

Note

  • Open the 5.5.use_internal_library.ino file under the path of 3in1-kit\basic_project\5.5.use_internal_library.

  • Or copy this code into Arduino IDE.

  • Or upload the code through the Arduino Web Editor.

Once you finish uploading the codes to the R3 board, you can see the servo arm rotating in the range 0°~180°.

How it works?

By calling the library Servo.h, you can drive the servo easily.

#include <Servo.h>

Library Functions：

Servo

Create Servo object to control a servo.

uint8_t attach(int pin);

Call pinMode() to turn a pin into a servo driver and return 0 on failure.

void detach();

Release a pin from servo driving.

void write(int value);

Set the angle of the servo in degrees, 0 to 180.

int read();

Return that value set with the last write().

bool attached();

Return 1 if the servo is currently attached.