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Intro to Embedded

2025

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Overview

Part 1 - Introduction

  • What is a microcontroller?
  • Setting up our development environment
  • Running our first program

Part 2 - Hardware Basics

  • LEDs
  • Resistors
  • Using a Breadboard
  • PWM

Part 3 - Sensors

  • Button
  • Potentiometer

Part 4 - Making some stuff!

Next week…

  • Wifi and bluetooth
  • More interesting sensors
  • Interrupts
  • MQTT & other protocols
  • Harder challenges!

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Requirements

  • Download VSCode

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  • Download the Platformio Extension

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What is a Microcontroller?

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  • Basically a tiny computer on a single circuit

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  • ESP32, STM32, Atmega328P

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  • GPIO pins interact with other hardware

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The ESP32

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  • Wifi & Bluetooth
  • Low power consumption
  • I/O peripherals (USART, ADC etc)
  • Lots of GPIO pins

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The ESP32

We must know pin numbers to access them in code.

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Search up “pinout diagram” for

whichever microcontroller you use.

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Creating a New Project

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Project Structure

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Serial Communication

Baud rate: The speed of communication (bits per second) between the microcontroller and computer

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Upload to ESP32

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Accessing GPIO pins

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Digital Outputs

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  • We can turn pins on or off through code
  • By changing the voltage running through pins, we affect the hardware connected to it

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In logic In the real world

ON HIGH TRUE 1 3.3 or 5V Vcc

OFF LOW FALSE 0 0V GND

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Light Emitting Diodes (LEDs)

Diode: A one-way valve for electric current.

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This means you must take care to wire LEDs

in the correct direction

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Light Emitting Diodes (LEDs)

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Resistors

Control voltage levels and prevent components from burning out

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Breadboard

source: https://www.build-electronic-circuits.com/breadboard/

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Let’s start wiring!!!

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Let’s start wiring!!!

Try to make the following circuit

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use a resistor between 200 - 5000 Ohms

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Wiring

What happens if we connect it to pin 2?

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How can we control LED brightness?

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Pulse Width Modulation (PWM)

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Pulse Width Modulation (PWM)

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Push Button

When pressed, the button closes

the circuit, allowing current to flow through

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Push Button

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Reading a Pin

‘reading’ will be either 0 or 1

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Push Button

What is the state of pin 2 when button is pressed?

What about not pressed?

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Pull Up and Pull Down

When setting a pin mode to input, we must specify whether it should be pulled to GND or 5V by default

INPUT_PULLUP => 5V by default

INPUT_PULLDOWN => GND by default

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Push Button Example

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Potentiometer

Provides variable resistance,

depending on where it is turned

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Potentiometer

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Choose Your Next Quest

https://github.com/ProgSoc/embedded2025/wiki

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Next Workshop

  • Ultrasonic Sensors
  • Servo Motors
  • RGB LEDs
  • Wifi & Bluetooth
  • More quests!

📍 Where: CB11.05.400 (iHub)

📆 When: Thursday, 11th September

⏰ Time: 6:00 pm - 8:00 pm

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Thank You