beginning arduino session 2 an introduction to hacking the world’s most popular microcontroller...

Beginning ArduinoSession 2

AN INTRODUCTION TO HACKING THE WORLD’S MOST POPULAR MICROCONTROLLER PLATFORM

http://scn.sap.com/community/developer-center/hana/blog/2014/12/08/iot-with-sap-hana-dev

2.0 – Welcome and Introduction2.1 – Components used in this Project.2.2 – Exploring a Switch and its effects in a digital system.

2.3 – De-bouncing a switch 2.3.1 – Blink Without Delay 2.4 – Exploring the 4 main uses for a resistor 2.4.1 – Current Limiting 2.4.2 – Voltage Division 2.4.3 – Pull Down 2.4.4 – Pull Up

Today’s Agenda

2.5 – Exploring Speakers and Piezo Buzzers 2.5.1 – How a speaker works vs a Piezo speaker 2.6 – PWM outputs, what are they? A detailed look into Pulse width Modulation

2.7 – The RGB LED 2.8 – Exploring Libraries. 2.9 – Using Tabs, creating our own Lib 2.10 – Using integer Arrays 2.11 – Bringing it all together: Name That Tune 2.12 – Serial Feedback 2.13 - Shields

Today’s Agenda (cont.)

TAC Switch x 4Peizo Buzzer x 1RGB Breakout x 1

Components used in this Project.

Circuit:

When a switch is pressed in a circuit it casues the line voltage to “bounce”

Bouncing

Sample of a switch press

When timing is crucial or multiple things need to happen during the void loop(), the delay() command can become a big problem.

Open example > Basic > Blink

Blink

void setup() { pinMode(13,OUTPUT); pinMode(9,OUTPUT); pinMode(2,INPUT); }

Modify the Blink Sketch setup

void loop() { digitalWrite(13, HIGH); // turn the LED on (HIGH is the voltage level) delay(1000); // wait for a second digitalWrite(13, LOW); // turn the LED off by making the voltage LOW delay(1000); // wait for a second if(digitalRead(2) == LOW) digitalWrite(9,HIGH); else digitalWrite(9,LOW); }

Modify the Blink Sketch loop

Open sketch examples > Digital > Blink without delay

Blink Without delay()

Modify the sketch in the same way, what happens differently?

Modify the sketch

Current Limiting Voltage Division Pull Down Pull Up

Four Main uses for a Resistor

Current Limiting Resistor

Voltage Divider

Pull-UP

void setup() { pinMode(6,OUTPUT); }

void loop() { if(digitalRead(2) == LOW) digitalWrite(6,HIGH); else digitalWrite(6,LOW); }

Example of INPUT_PULLUP

The Piezo Buzzer

Pulse Width ModulationIs a DC voltage that is turned ON and OFF at different rates. The voltage has 2 states, 0 and Vcc

PWM

PWM

A Low pass Filter will smooth a PWM signal back to a DC voltage.

Low Pass Filter

• Single Color• Bi-Color• Tri-Color• RGB

Types of LEDs

The RGB LED provided in your kit is mounted on a Breakout board.

A breakout board provides all the nessesary supporting electronics so it can be used easily and quickly for proto typeing.

The RGB LED with your Kit

void setup() { pinMode(6,OUTPUT); pinMode(9,OUTPUT); pinMode(10,OUTPUT); }

void loop() { digitalWrite(9,HIGH); delay(300); digitalWrite(9,LOW); digitalWrite(10,HIGH); delay(300); digitalWrite(10,LOW); digitalWrite(6,HIGH); delay(300); digitalWrite(6,LOW); }

RGB LED test

Libraries are chunks of code writen for specific, and often repetitive task.

# include <Lib_Name>or

# include “Lib_Name”

Libraries

Go to – https://github.com/shirriff/Arduino-IRremote/releases

Download the IRremote.zip file

Download and install Libraries.

Method 1 Automatic – Go to Sketch > Input Library > Add Library. Navigate to the file just downloaded and select it.

Method 2 Manually extract the Library and copy the folder to the Lib folder within the Arduino sketch folder.

Two ways to install a Library

// Our Lib of Pitches

#define NOTE_G1 49 #define NOTE_B2 123 #define NOTE_F3 175 #define NOTE_G4 392

Create a Library

An array is a collection of variables that are accessed with an index number.

Arrays are Zero indexed.

Arrays

// Call my Lib #include "pitches.h"

// Define my Array int BP[] = {NOTE_G4, NOTE_B2, NOTE_F3, NOTE_G1};

Bringing it all together

// Declare my variabls int INDEX = 2; // Start button

int redLEDPin = 9; int greenLEDPin = 10; int blueLEDPin = 6;

Bringing it all together

// Set my pin modes void setup() { pinMode(2,INPUT_PULLUP); pinMode(3,INPUT_PULLUP); pinMode(4,INPUT_PULLUP); pinMode(5,INPUT_PULLUP); pinMode(13,OUTPUT); pinMode(redLEDPin,OUTPUT); pinMode(greenLEDPin,OUTPUT); pinMode(blueLEDPin,OUTPUT); }

Bringing it all together

// My loop void loop() { if(digitalRead(INDEX) == LOW) { tone(8,BP[INDEX-2]); RGBWrite(random(100),random(100),random(100)) ; while(digitalRead(INDEX) == LOW) { } RGBWrite(0,0,0); noTone(8); } INDEX=INDEX+1; if(INDEX > 5) INDEX = 2; }

Bringing it all together

Press keys in this order

1 – 2 – 3 – 4 – 2

Name that tune

There is 1 UART (universal asynchronous receiver/transmitter) on the Arduino Uno

The Serial port uses Pin 0 and 1

Pin 0 = RX or Data Receive Pin 1 = TX or Data Transmit

The USB connection uses the same UART

Serial Feedback

int R = random(100); int G = random(100); int B = random(100); if(digitalRead(INDEX) == LOW) { Serial.print(INDEX); Serial.print("|"); Serial.print(R); Serial.print("|"); Serial.print(G); Serial.print("|"); Serial.println(B); // Serial.println() adds a line feed to the end tone(8,BP[INDEX-2]); RGBWrite(R,G,B) ;

Add to the script

A Shield is a supportive board that plugs into the Arduino to extend the Arduino’s ability and reduces the amount of bread boarding needed.

There’s a Shield for that…

http://shieldlist.org/

https://learn.sparkfun.com/tutorials/arduino-shields

Shields

Challenge #1 – Use a switch-case and make specific colors light up based on the tone being played.

Challenge #2 – Team up and use 8 buttons to make a 8 Key Keyboard

Challenge #3 Use the Ir Lib to play sounds from your Remote.

Challenge