By Jay Gupta for NTU Open Source Society
This workshop is based on Arduino Uno and assumes elementary knowledge of C++ Programming.
Disclaimer - This document is only meant to serve as a reference for the attendees of the workshop. It does not cover all the concepts or implementation details discussed during the actual workshop.
When: Friday, 27 Mar 2020. 6:30 PM - 8:30 PM
Where: LHN-TR+19, The Arc - Learning Hub North (LHN), Nanyang Technological University
Who: NTU Open Source Society
If you find any mistake (typo or anything else), please make a pull request or post an issue! Thanks!
A microcontroller is a computer system on a chip that does a job. It contains an integrated processor, memory (a small amount of RAM, program memory, or both), and programmable input/output peripherals, which are used to interact with things connected to the chip. A microcontroller is different than a microprocessor, which only contains a CPU.
Arduino is an open-source electronics platform based on easy-to-use hardware and software.
Arduino boards are able to read inputs - light on a sensor, a finger on a button, or a Twitter message - and turn it into an output - activating a motor, turning on an LED, publishing something online. You can tell your board what to do by sending a set of instructions to the microcontroller on the board.
We are going to use Arduino Uno for this Workshop
- Vin, 5V, 3.5V, GND - To provide power and ground the circuit.
- Reset - Resets the microcontroller.
- Analog Pins (A0-A5) - Receive Analog Input (0 - 5V).
- Digital Pins (0-13) - Receive and Transmit Digital Data.
- Rx(0), Tx(1) - Receive and Transmit Serial Data.
- Interrupt Pins (2, 3) - Trigger an external Interrupt.
- PWM Pins (3, 5, 6, 9, 10, 11) - Provide PWN Output. PWM is a technique to get analog results with digital means.
- SPI Pins (10, 11, 12, 13) - Used for SPI Communication.
- InBuilt LED (13) - Trigger the in-built LED.
Arduino code is written in C++ with an addition of special methods and functions.
// Declare Global Variables
// Set-Up the Arduino Board (Specify PINs to use as I/O) - PREPERATION BLOCK
void setup()
{
// Code
}
// Main Program - EXECUTION BLOCK
void loop()
{
// Code
}// Internal LED Blinker Circuit
int ledPin = 13;
void setup()
{
// initialize pins as OUTPUT
pinMode(ledPin, OUTPUT);
}
void loop()
{
// Blink the LED
digitalWrite(ledPin, HIGH);
delay(1000);
digitalWrite(ledPin, LOW);
delay(1000);
}
// Intelligent ThermoStat
// Hot Temperature (in Celsius)
const int hot = 35;
// Cold Temperature (in Celsius)
const int cold = 20;
void setup() {
pinMode(A2, INPUT); // Temperature Sensor
pinMode(2, OUTPUT); // Blue LED - Indicate Cold
pinMode(3, OUTPUT); // Green LED - Indicate Neutral
pinMode(4, OUTPUT); // Red LED - Indicate Hot
Serial.begin(9600);
}
void loop() {
int sensor = analogRead(A2);
// Voltage Conversion
float voltage = (sensor / 1024.0) * 5.0;
float tempC = (voltage - .5) * 100;
Serial.print("Temperature Detected: ");
Serial.println(tempC);
if (tempC < cold) {
// It is Cold
digitalWrite(2, HIGH); // Blue LED On
digitalWrite(3, LOW); // Green LED Off
digitalWrite(4, LOW); // Red LED Off
Serial.println("It is Cold");
}
else if (tempC >= hot) {
// It is Hot
digitalWrite(2, LOW); // Blue LED Off
digitalWrite(3, LOW); // Green LED Off
digitalWrite(4, HIGH); // Red LED On
Serial.println("It is Hot.");
}
else {
// It is Neutral
digitalWrite(2, LOW); // Blue LED Off
digitalWrite(3, HIGH); // Green LED On
digitalWrite(4, LOW); // Red LED Off
Serial.println("It is Fine.");
}
delay(1000);
}
// Measuring the Speed of Sound
// Ultrasonic Sensor PIN Configuration
int trigPin = 13;
int echoPin = 11;
// Measuring Ping Time
float pingTime;
float speedOfSound;
// Object Distance from Ultrasonic Sensor (in Inches)
float targetDistance = 6;
void setup()
{
Serial.begin(9600);
// Ultrasonic Sensor PIN Configuration
pinMode(trigPin, OUTPUT);
pinMode(echoPin, INPUT);
}
void loop()
{
// Generate a Pulse
digitalWrite(trigPin, LOW);
delayMicroseconds(2000);
digitalWrite(trigPin, HIGH);
delayMicroseconds(10);
digitalWrite(trigPin, LOW);
// Measure Ping Time
pingTime = pulseIn(echoPin, HIGH);
// Calculating Speed of Sound
speedOfSound = 2 * targetDistance / pingTime;
speedOfSound = speedOfSound / 63360 * 1000000 * 3600;
speedOfSound = speedOfSound * 0.44;
Serial.print("The speed of sound is ");
Serial.print(speedOfSound);
Serial.println(" m/s");
delay(3000);
}Congratualations on completing the very basics of Arduino!
We have barely scratched the surface. The Arduino world is vast and there is a lot more that we can learn from tons of sensors such as Wi-Fi. Bluetooth, Cameras & GPS to advanced Motor & Servo control.
