Arduino mini-lessons

29 Jul 2024, 04:18

Lesson 1: Introduction to the Arduino Platform

Arduino is a platform for developing electronic devices that allows you to create simple and complex projects using microcontrollers. One of the popular directions in Arduino development is the integration with STM32 microcontrollers. In this lesson, we will explore how to work with the Arduino platform based on STM32.

1. Introduction to Arduino and STM32:

Arduino is an open-source platform with hardware and software that enables the creation of prototypes for electronic devices. STM32 is a family of microcontrollers produced by STMicroelectronics, known for their high performance and versatility.

2. Connecting to the Arduino IDE environment:

Step 1: Install the Arduino IDE if you don't have it yet.
Step 2: Open the Arduino IDE and go to the "File" menu -> "Preferences".
Step 3: In the "Additional Boards Manager URLs" field, add the link to the board manager for STM32:

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https://raw.githubusercontent.com/stm32duino/BoardManagerFiles/master/STM32/package_stm_index.json

Step 4: Go to the "Tools" menu -> "Board" -> "Boards Manager".
Step 5: Enter "STM32" in the search bar and install the "STM32 Cores" package from "STMicroelectronics".
Step 6: After installation, select the appropriate STM32 board model from the "Tools" -> "Board" menu.
Step 7: Now you can create projects for STM32 in the Arduino IDE environment.

3. Example: Simple project for STM32 on the Arduino platform:

Let's create a simple project for the STM32 microcontroller that will blink an LED.
Step 1: Connect the STM32 board to the computer via USB.
Step 2: Create a new project in the Arduino IDE.
Step 3: In the "Tools" section, select the appropriate STM32 board model.
Step 4: Insert the following code:

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const int ledPin = PC13; // LED pin

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

void loop() {
digitalWrite(ledPin, HIGH);
delay(1000);
digitalWrite(ledPin, LOW);
delay(1000);
}

Step 5: Save and upload the code to the STM32 microcontroller.

4. Conclusion:

In this lesson, we have familiarized ourselves with the Arduino platform and its compatibility with STM32 microcontrollers. We have learned how to connect the board to the Arduino IDE environment and created a simple project for blinking an LED. This is just the beginning of the adventure in the world of development with STM32 and Arduino. With this knowledge, you can develop more complex projects and delve deeper into the capabilities of the platform.

29 Jul 2024, 04:40

Peripheral devices such as timers and counters play an important role in microcontrollers, providing the ability to control time intervals, periods, and events. In this lesson, we will explore how to work with timers and counters on the Arduino platform, as well as provide practical examples and explanations on how to connect them.

Basics of working with timers and counters

Timers and counters are hardware devices designed for generating precise time intervals or processing events. They typically have registers for setting parameters such as frequency divider and operating mode. Arduino provides libraries and functions to simplify working with these devices.

Connecting and configuring timers on Arduino

Special registers are used to work with timers on Arduino, allowing you to configure the operating mode, frequency divider, and counter. Let's consider a practical example of generating a delay using a timer:

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const int ledPin = 13;

void setup() {
pinMode(ledPin, OUTPUT);

// Setting up timer 2 for generating a delay
TCCR2A = 0; // Normal mode
TCCR2B = (1 << CS22) | (1 << CS21) | (1 << CS20); // Divider set to 1024
TIMSK2 = (1 << TOIE2); // Enable interrupt on overflow
}

ISR(TIMER2_OVF_vect) {
digitalWrite(ledPin, HIGH); // Turning on the LED
delay(1000); // Delay of 1 second
digitalWrite(ledPin, LOW); // Turning off the LED
}

void loop() {
// Other tasks can be performed here
}

Generating signals using timers

Timers can be used to generate signals of a specific frequency. Let's consider an example of blinking an LED using a timer:

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const int ledPin = 13;

void setup() {
pinMode(ledPin, OUTPUT);

// Setting up timer 1 for signal generation
TCCR1A = (1 << COM1A0); // Clearing on compare match with OCR1A
TCCR1B = (1 << WGM12) | (1 << CS10); // CTC mode and divider set to 1
OCR1A = 15624; // Value to achieve a frequency of around 1 Hz
}

void loop() {
// Other tasks can be performed here
}

Using counters

Counters allow tracking the number of events or pulses. For example, you can create a counter to count button presses:

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const int buttonPin = 2;
volatile int buttonCount = 0;

void setup() {
pinMode(buttonPin, INPUT_PULLUP);
attachInterrupt(digitalPinToInterrupt(buttonPin), countButton, FALLING);
Serial.begin(9600);
}

void loop() {
// Printing the counter value to the Serial Monitor
Serial.println(buttonCount);
delay(1000);
}

void countButton() {
buttonCount++;
}

Conclusion

Working with timers and counters on the Arduino platform provides the ability to precisely control time intervals and events. We have covered basic examples of using timers and counters, as well as understood how to connect and configure them on Arduino. These skills will be useful when creating various projects that require time synchronization and event processing.

29 Jul 2024, 04:51

In this lesson, we will explore how to work with Analog-to-Digital Conversion (ADC) and Digital-to-Analog Conversion (DAC) on the Arduino platform. These processes allow the microcontroller to interact with analog signals and create analog outputs, which can be useful for a variety of applications.

Analog-to-Digital Conversion (ADC)

ADC enables the conversion of an analog signal, such as voltage from a sensor, into a digital format that can be processed by the microcontroller. Arduino typically has several analog pins where analog signals can be measured.

Example of working with ADC:

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const int analogPin = A0; // Analog signal pin

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

void loop() {
int analogValue = analogRead(analogPin); // Read analog value
float voltage = analogValue * (5.0 / 1023.0); // Convert to voltage
Serial.print("Analog Value: ");
Serial.print(analogValue);
Serial.print(", Voltage: ");
Serial.println(voltage);
delay(1000);
}

Digital-to-Analog Conversion (DAC)

Digital-to-Analog Conversion allows creating analog output signals controlled by the microcontroller. Arduino does not have a built-in DAC, but you can use techniques to approximate an analog signal.

Example of working with DAC (PWM): changing the brightness of an LED

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const int ledPin = 9; // PWM pin
int brightness = 0; // Initial brightness
int fadeAmount = 5; // Brightness increment step

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

void loop() {
analogWrite(ledPin, brightness);

brightness += fadeAmount; // Increase brightness by step

if (brightness <= 0 || brightness >= 255) {
fadeAmount = -fadeAmount; // Change the direction of brightness change
}

delay(30); // Delay for a visible brightness change effect
}

Conclusion

Working with analog-to-digital and digital-to-analog conversion is an important aspect in many Arduino projects. We have covered the basics of using ADC for measuring analog signals and applying PWM for creating analog outputs. These skills open up possibilities for creating more complex and interesting projects involving analog data processing and controlling analog devices.

29 Jul 2024, 05:07

In this lesson, we will explore how to work with UART/USART, I2C, and SPI on the Arduino platform. These protocols provide the ability to exchange data between microcontrollers and other devices, which can be useful for creating a variety of projects.

1. Working with UART/USART:

UART (Universal Asynchronous Receiver-Transmitter) or USART (Universal Synchronous Asynchronous Receiver-Transmitter) are standard serial communication methods used for transmitting data between devices. Many sensors, modules, and computers support UART communication.

Example of working with UART:

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void setup() {
Serial.begin(9600); // Starting UART communication at a speed of 9600 bits per second
}

void loop() {
if (Serial.available()) { // If data is available for reading
char data = Serial.read(); // Read the data
Serial.print("Received: ");
Serial.println(data);
}
}

2. Working with the I2C protocol:

I2C (Inter-Integrated Circuit) is a communication protocol that allows multiple devices to be connected to a single bus. I2C is used for data exchange between microcontrollers and other devices, such as sensors, displays, and more.

Example of working with I2C:

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#include <Wire.h> // Include the Wire library for working with I2C

void setup() {
Wire.begin(); // Initialize the I2C bus
Serial.begin(9600);
}

void loop() {
Wire.beginTransmission(8); // Start the transmission to the device with address 8
Wire.write('A'); // Transmit the data
Wire.endTransmission(); // End the transmission

delay(500);

Wire.requestFrom(8, 1); // Request data from the device with address 8
if (Wire.available()) {
char data = Wire.read(); // Read the data
Serial.print("Received: ");
Serial.println(data);
}

delay(1000);
}

3. Working with the SPI protocol:

SPI (Serial Peripheral Interface) is a synchronous communication protocol between a microcontroller and peripheral devices. It is used for data exchange with various devices such as displays, sensors, radio modules, and more.

Example of working with SPI:

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#include <SPI.h> // Include the SPI library

const int slaveSelectPin = 10; // Device select pin

void setup() {
SPI.begin(); // Initialize SPI
pinMode(slaveSelectPin, OUTPUT);
digitalWrite(slaveSelectPin, HIGH); // Disable the default device
Serial.begin(9600);
}

void loop() {
digitalWrite(slaveSelectPin, LOW); // Enable the device
SPI.transfer('A'); // Transfer data over SPI
digitalWrite(slaveSelectPin, HIGH); // Disable the device

delay(500);

digitalWrite(slaveSelectPin, LOW);
char data = SPI.transfer(0); // Receive data from the device
digitalWrite(slaveSelectPin, HIGH);

Serial.print("Received: ");
Serial.println(data);

delay(1000);
}

Conclusion:

Working with UART/USART, I2C, and SPI are key skills that open up a lot of possibilities for data exchange between microcontrollers and other devices. We have looked at examples of working with each of these protocols on the Arduino platform, which will allow you to create more complex and interesting projects by interacting with various devices and modules.