Elektor ESP32 Programming Micro Controllers User Manual

Tekniset tiedot

• Tuotteen nimi: Programming Microcontrollers in C/C++ Using Arduino
• Tekijä: Clemens Valens
• Tuetut alustat: Arduino UNO, Raspberry Pi Pico, ESP32
• ISBN: 978-3-89576-720-3 (Print), 978-3-89576-721-0 (eBook)

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The book starts with an introduction to programming ESP32 microcontrollers using the Arduino IDE. It outlines:

• The scope and capabilities of ESP32 boards.
• Setting up a programming environment.
• Applications of microcontrollers in IoT, robotics, home automation, and sensor-based systems.
• Guidance for beginners to transition from simple sketches to full-fledged embedded projects.

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The Arduino IDE
This chapter focuses on setting up and using the Arduino IDE for ESP32 development. Key sections include:

Yliview of the Arduino IDE

• Explains the IDE interface: menus, toolbars, and workspace.
• Highlights key features for coding, compiling, and debugging.

Installing and Launching the IDE

• Step-by-step installation on Windows, macOS, and Linux.
• Adding ESP32 board support via the Board Manager.

Using the Boards Manager

• Installing ESP32 support.
• Selecting the correct board for your project (DevKit, NodeMCU, etc.).

Upload Programs

• Compiling sketches and uploading them to the ESP32.
• Troubleshooting upload errors (common COM port or driver issues).

Using the Library Manager

• Adding essential libraries for sensors, displays, and communication modules.
• Example: Adafruit_Sensor, Wire, SPI.

Using the Serial Monitor

• Viewing output for debugging.
• Sending commands to ESP32 via Serial.

Using the Serial Plotter

• Real-time visualization of data, such as analog sensor readings.
• Platform Notes & Best Practices

Optimizing workflow.

• Keeping libraries updated.
• Saving and organizing sketches.

Brief Introduction to C/C++ Programming
This chapter is for readers who are new to programming:

• Tietotyypit
  • int, float, char, boolean, and their ESP32 memory considerations.
• Variables and Constants
  • How to declare, initialize, and use variables in ESP32 sketches.
  • Ero välillä const ja #define.
• Control Structures
  • if, else, switch, loops (for, while, do-while) for decision-making.

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• Creating reusable code blocks.
• Passing arguments, return types, and scope of variables.

Hello-World Examples

• Simple “Blink” LED project.
• Serial.print() examples to display messages.

Writing and Running Your First Arduino Program
Practical introduction to writing code:

• Arduino IDE Workflow
  • Stepwise approach: writing → compiling → uploading → testing.
• Creating Your First Program
  • Writing a simple sketch (LED blink or serial output).
• Uploading the Program
  • Selecting the correct port and board type.
  • Common errors and solutions.
• Running on Different Target Platforms
  • ESP32 DevKit, NodeMCU, or WROVER boards.
• Testing Serial Communication
  • Serial monitor output for debugging.
  • Using Serial.read() and Serial.println().

Working with Digital Signals
Focuses on digital electronics concepts:

• What Are Digital Signals?
  • HIGH/LOW logic, 0/1 representation.
• Configuring Digital Pins
  • pinMode(pin, INPUT/OUTPUT).
  • Internal pull-up/pull-down resistors.
• Controlling an LED
  • Example: blinking LED with digitalWrite().
• Reading a Pushbutton
  • Using digitalRead() to detect button presses.
  • Debouncing strategies.
• Pushbutton-Controlled LED Sequence
  • Example project combining multiple inputs and outputs.

Working with Analog Signals
Analog signals and conversion:

• What Are Analog Signals?
  • Jatkuva voltage signals vs discrete digital signals.
• Measuring Analog Signals
  • Using ADC (Analog-to-Digital Converter) on ESP32.
• Displaying Voltage on Serial Port
  • Example: reading a potentiometer and printing values.
• Generating Analog-like Signals
  • PWM (Pulse Width Modulation) to simulate analog output.
• LED-kirkkauden säätö
  • Using analogWrite() / ledcWrite() for ESP32.
• Using a Potentiometer
  • Adjusting LED brightness or motor speed interactively.
• True Analog Output (DAC)
  • Using DAC channels on ESP32 for precise analog signals.

Working with the Serial Port
Serial communication essentials:

• What Is Serial Communication
  • UART basics and connection to PC or peripherals.
• Tiedonsiirtonopeus ja datamuoto
  • Choosing correct baud rate (9600, 115200).
• Opening a Serial Connection
  • Serial.begin(), Serial.available().
• Serial.print() vs Serial.println()
  • Differences for formatting data.
• Sending Numbers and Text
  • Käyttämällä String or numeric types.
• Receiving Data Over Serial
  • Serial.read(), parsing commands.
• Controlling an LED via Serial
  • Turning outputs ON/OFF remotely.

Working with I²C
I²C communication protocol:

• What Is I²C?
  • Master-slave protocol for multiple devices.
• Pull-Up Resistors
  • Required for I²C lines.
• ²C Pins on ESP32
  • Default: SDA, SCL (can be reconfigured).
• Using Wire Library
  • scan() devices, read(), write() functions.
• Examples
  • Reading temperature sensors, OLED displays.
• Platform Notes & Common Pitfalls
  • Voitage compatibility, bus speed considerations.

Working with SPI
SPI communication:

• What Is SPI?
  • Faster alternative to I²C for single master devices.
• SPI Pins on ESP32
  • MOSI, MISO, SCLK, CS pins.
• Using SPI Library
  • SPI.begin(), SPI.transfer().
• SPI Modes and Timing
  • CPOL/CPHA, clock polarity and phase.
• Comparison with I²C and Serial
  • Trade-offs in speed, wiring, and device support.

Working with Time
Timing and scheduling tasks:

• delay() vs millis()
  • Blocking vs non-blocking code.
• Measuring Short Intervals
  • micros() function for precise timing.
• Hardware Timers
  • ESP32 has multiple timers for periodic events.

Working with Interrupts
Handling asynchronous events:

• What Is an Interrupt?
  • Immediate response to GPIO or timers.
• Writing ISRs
  • Best practices, avoiding long delays.
• Debouncing Buttons
  • Ensuring stable input readings.
• Sharing Data Between ISR and loop()
  • Using volatile variables.

Interacting with the Real World
Connecting sensors and actuators:

• Transducers and Sensors
  • Temperature, humidity, distance, motion sensors.
• Key Sensor Characteristics
  • Accuracy, resolution, response time.
• Interfacing Sensors
  • Using analog/digital/I²C/SPI signals.
• toimilaitteet
  • Relays, motors, servos, LEDs.
• Safety & Power Considerations
  • Oikea tilavuustage, current, and protection measures.

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ISBN 978-3-89576-720-3 Print

• ISBN 978-3-89576-721-0 eBook
• www.elektor.com
• Editor: Clemens Valens
• Prepress tuotanto: D-Vision, Julian van den Berg
• Tulostimet: Ipskamp, Enschede, Alankomaat

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