Arduino Tutorial

By LiterallyTheOne

5: Analog

Introduction

• Previous tutorial: Serial Communication
• This tutorial: Analog

Analog Read

• digitalRead
• analogRead (10bit)

Analog pins

• 6 pins: A0 to A5
• Showed by yellow

Potentiomenter

• Creates voltage between and
• In SimulIDE: Passive/Resistors/Potentiometer
• pins and a rotating button

Connect potentiometer

Potentiomenter and Arduino

Write the code for analogRead

#include <Arduino.h>

void setup()
{
  Serial.begin(9600);
}

void loop()
{
  int our_input = analogRead(A0);
  Serial.println(String(our_input));
  delay(1000);
}

Result of analogRead

PWM

• Pulse Width Modulation
• Technique for controlling the power
• Arduino uses it for writing analog values

PWM duty cycle

Analog Write pins

• Uses PWM
• There are 6 pins: 3, 5, 6, 9, 10, 11
• In arduino: ~
• In SimulIDE: PWM

Analog Write

• digitalWrite:
• analogWrite:
  • duty cycle
  • duty cycle

Conect LED

Write code for analog write

#include <Arduino.h>

void setup()
{
  pinMode(3, OUTPUT);
}

void loop()
{
  for (int i = 0; i < 256; i++)
  {
    analogWrite(3, i);
    delay(10);
  }
}

Result of analogWrite

See PWM with Oscope

Combining both

Write the code for combining both

#include <Arduino.h>

void setup()
{
  pinMode(3, OUTPUT);
}

void loop()
{
  int our_input = analogRead(A0);
  int brightness = map(our_input, 0, 1023, 0, 255);
  analogWrite(3, brightness);
  delay(1000);
}

map function

• maps our input to the range that we want
• first argument: input
• second and third: input's range
• forth and fifth: output's range

Result of combining both

Result of combining both with Oscope

DC Motor

• Converts electrical energy into rotation
• Examples:
  • Drill
  • Saw
  • Toys

mosfet

• DC motor takes to much current
• Should not be connected directly to Arduino pin
• We use mosfet to write analog data

Connect DC Motor to Arduino

Result of DC motor

• Code is the same

Servo motor

• Precise control
• Robotics
• Position motor with PWM
• Simple DC Servo motor
• [-90, 90] ([0, 180])
• frequency:

Connect Servo motor to Arduino

Servo library

• Generates frequency
• in PlatformIO:

lib_deps =
    ...
    arduino-libraries/Servo

• in main.cpp:

#include <Servo.h>

Servo functions

• Create an object

Servo my_servo;

• identify the pin

my_servo.attach(3);

• Write angle

my_servo.write(45);

Result of Servo motor

Result of Servo motor with Oscope

Combine All

Link to the tutorial and materials