Introduction

This week, I worked with different microcontrollers and completed both group and individual assignments. In our group work, we demonstrated and compared the toolchains and development workflows for various embedded architectures, which helped me understand the differences and similarities between them. For my individual assignment, I studied the datasheet of a microcontroller and wrote a program for an embedded system. I tested the program to make the microcontroller interact with input and output devices, as well as communicate using wired connections. This experience gave me practical knowledge of how embedded systems work and how to develop programs for them.

Individual assignment

Task:

browse through the data sheet for a microcontroller.
write and test a program for an embedded system using a microcontroller to interact (with input &/or output devices)

Group assignment

Task:

Demonstrate and compare the toolchains and development workflows for available embedded structures.

Comparison of Mixrocontroller Architectures

Parameters	Arduino Uno	ESP32-WROOM	ESP32 XIAO
Microcontroller	ATmega328P	ESP32	ESP32
Core	Single core	Dual core	Dual core
Architecture	8-bit AVR RISC	32-bit Xtensa LX6	32-bit Xtensa LX6
Clock Speed	16 MHz	Up to 240 MHz	Up to 240 MHz
Operating Voltage	5V	3.3V	3.3V
GPIO Voltage	5V	3.3V	3.3V
Digital Pins	14	Up to 34	Up to 11
PWM Pins	6	Up to 16	Up to 11
Analog Pins	6	Up to 18	Up to 8
Communication	UART, SPI, I2C	UART, SPI, I2C, I2S	UART, SPI, I2C, I2S
WiFi	No	Yes	Yes
Bluetooth	No	Yes	Yes
Programming Language	C/C++	C/C++, MicroPython	C/C++, MicroPython
On-board LED Pin	D13	GPIO2	GPIO2
Flash Memory	32 KB	4 MB	4 MB
RAM	2 KB SRAM	520 KB SRAM	520 KB SRAM
USB Interface	USB Type-B	Micro-USB	USB Type-C
Advantages	Best for beginners and basic embedded learning	Best for IoT and wireless applications	Small size, powerful, and suitable for compact IoT projects

Toolchain and Development Workflow Comparison

A toolchain is a set of software tools used to write, compile, upload, and debug programs in a microcontroller. In this group assignment, we used Arduino IDE and Thonny IDE to program Arduino Uno, ESP32-WROOM, and ESP32 XIAO.

Toolchain Component	Arduino Uno	ESP32-WROOM	ESP32 XIAO
Architecture	AVR 8-bit	Xtensa 32-bit	Xtensa 32-bit
Programming Language	C/C++	C/C++, MicroPython	C/C++, MicroPython
IDE (Editor)	Arduino IDE	Arduino IDE, Thonny IDE	Arduino IDE, Thonny IDE
Compiler	AVR-GCC	Xtensa-ESP32-GCC	Xtensa-ESP32-GCC
Uploader Tool	avrdude	esptool	esptool
Firmware	Arduino Bootloader	ESP32 Firmware / MicroPython Firmware	ESP32 Firmware / MicroPython Firmware
Connection Type	USB Type-B	Micro-USB	USB Type-C
Execution Method	Compiled and uploaded	Compiled or Interpreted	Compiled or Interpreted

Development Workflow (Arduino IDE)

1. Write program in Arduino IDE
2. Select board (Arduino Uno / ESP32-WROOM / ESP32 XIAO)
3. Compile the program
4. Upload program using USB
5. Microcontroller executes the program

Development Workflow (MicroPython)

1. Install MicroPython firmware on ESP32
2. Open Thonny IDE
3. Write Python program
4. Upload program to microcontroller
5. Program executes immediately

Comparison Summary

• Arduino Uno uses AVR-GCC compiler and supports C/C++ programming.
• ESP32-WROOM and ESP32 XIAO support both C/C++ and MicroPython.
• Arduino IDE is used for compiling and uploading programs.
• Thonny IDE is used for MicroPython programming.
• MicroPython is easier for beginners and faster for testing.
• C/C++ provides better performance and hardware control.

Conclusion

From this comparison, Arduino Uno is suitable for beginners and basic embedded programming. ESP32-WROOM and ESP32 XIAO provide advanced features such as WiFi, Bluetooth, and higher processing speed. MicroPython provides easier development, while C/C++ provides better performance and control.

Group Assignment Week 4

Embedded Programming

Embedded programming is writing code for small computers inside devices. These devices are called embedded systems, such as microwaves or smartwatches. The code makes the device perform specific tasks, like turning on lights or reading sensors. It runs directly on the devices microcontroller or processor. Embedded programming is used in everyday electronics, cars, and smart gadgets.

Embedded Systems

Embedded systems are special computers built into devices to perform specific tasks. They are found in everyday items like washing machines, cars, microwaves, and smartwatches. Unlike regular computers, embedded systems focus on one function and work efficiently with limited memory and processing power. They use microcontrollers or processors to read inputs from sensors, control outputs like motors or lights, and sometimes communicate with other devices.

An embedded system embeds several key elements that make it work as a small, dedicated computer inside a device.
It has a mix of hardware and software, including a microcontroller or microprocessor that acts as the brain to execute programs, and memory to store programs and data, such as RAM for temporary storage and Flash or ROM for permanent storage.
It also includes input devices or sensors to detect signals from the environment, like temperature sensors, buttons, or light sensors, and output devices or actuators, such as motors, LEDs, or displays, to act on the environment based on program instructions. Software or firmware controls the systems behavior, while communication interfaces allow it to connect with other devices using wired connections like UART, SPI, or I2C, or wireless connections like Bluetooth or Wi-Fi.
Finally, a power supply provides the electricity needed for all the components to function.
In short, an embedded system embeds a processor, memory, input/output devices, software, and power, all working together to perform a specific task.

What is microcontroller

A microcontroller is a small computer built on a single chip. It contains a processor, memory, and input/output ports all in one place. Microcontrollers are used to control devices and perform specific tasks in embedded systems. They are commonly found in everyday electronics like microwaves, cars, and smart gadgets.

What is microprocessor

A microprocessor is the central processing unit (CPU) of a computer on a single chip. It performs calculations, processes data, and executes instructions from programs. Unlike a microcontroller, a microprocessor usually needs external memory and input/output components to work. Microprocessors are used in personal computers, laptops.

Difference between microcontroller and microprocessor

microcontroller	microprocessor
A microcontroller has a processor, memory, and input/output ports all on one chip	A microprocessor only has a CPU and needs external memory and I/O devices.
Microcontrollers are used for specific tasks in embedded systems.	Microprocessors are used in general-purpose computers and devices needing high-speed processing.
Microprocessors are faster and handle complex tasks.	Microcontrollers are slower but efficient for simple, dedicated tasks.
Microcontroller has built-in RAM and ROM/Flash.	Microprocessor requires external memory.

Microcontrollers and their Datasheets overview

1.Arduino UNO

The Arduino Uno is a microcontroller development board based on the ATmega328P microcontroller. It is widely used in embedded systems, rapid prototyping, and educational applications. The board provides digital and analog input/output pins, USB communication interface, and power regulation circuitry, making it suitable for controlling electronic components such as LEDs, sensors, and motors.

Datasheet for Arduino UNO

• Arduino Uno is based on the ATmega328P microcontroller.
• The board operates at 5V operating voltage.
• It has 14 digital input/output pins, out of which 6 support PWM.
• It has 6 analog input pins (A0-A5) with 10-bit resolution.
• The microcontroller runs at a clock speed of 16 MHz.
• It has 32 KB Flash memory, 2 KB SRAM, and 1 KB EEPROM.
• The board includes a USB interface for programming and power supply.
• It has a built-in LED connected to digital pin 13.

Embedded programming with Arduino

First, I searched for the Arduino IDE for Windows and downloaded it.	I installed the Arduino UNO version.

After installing, I opened the software and selected the Arduino Uno as the board and chose the correct port to connect my Arduino. Then I went to the Examples section and opened the built-in LED blink program.	I uploaded this program to the Arduino to test if the board was working properly.

After uploading, the onboard LED started blinking, which confirmed that the Arduino board was connected correctly and working successfully.

I connected an LCD Display to the Arduino Uno and used a potentiometer to adjust the screen contrast so the text is clearly visible. After setting up the connections, I uploaded the program to the Arduino. Once the code was uploaded, the Arduino controlled the LCD and displayed the message "Hello Friends!!!" on the screen. This shows how we can use Arduino to send text and display messages on an LCD using embedded programming.

Arduino IDE code	Here is the final output.

Binary number system

The binary number system is the number system which uses only 2 digits: 0 and 1. computers and microcontrollers from Arduino and Espressif system understand binary system like for HIGH-ON-1, LOW-OFF-0.

binary address

A binary address is like a house address inside the microcontroller. The Arduino Uno has a small brain called the ATmega328P, and it stores information in many small places. Each place has its own address made using only 0 and 1. This is called a binary address. For example, an address can look like 00100101. When we upload code to Arduino, the code is saved in these addresses. The microcontroller then goes to the correct address, reads the code, and does the work like turning an LED ON or OFF. Binary uses only 0 and 1 because the microcontroller understands only these two signals, just like a switch that is either OFF (0) or ON (1).

This is the code using binary addresses.	I changed the timing, and I can see that the output changes. the blinking speed changes accordingly.

Hexadecimal address

A hexadecimal address is the memory location inside the microcontroller written using the hexadecimal number system, which uses numbers from 0 to 9 and letters A to F.The prefix 0x shows that the number is in hexadecimal format. These addresses help the microcontroller find and access the correct register to perform tasks like controlling LEDs, reading sensors, and communicating with other devices.

Here is the hexadecimal address code	And the output is as follows.

Micropython on ESP32

The ESP32-WROOM-32 (C-Type) is a powerful microcontroller development board based on the ESP32 chip, developed by Espressif Systems. This version includes a USB Type-C connector for programming and power supply, making it easier and more reliable to connect to the computer. It has built-in Wi-Fi and Bluetooth, which allows wireless communication with other devices and internet connectivity. The board provides multiple digital and analog input/output pins, which can be used to control LEDs, sensors, motors, displays, and other electronic components. It is widely used in embedded programming, IoT projects, automation systems, and wireless applications.

Datasheet for ESP32-WROOM-32

• ESP32-WROOM-32 is based on the ESP32 microcontroller
• The board operates at 3.3V operating voltage.
• It has built-in Wi-Fi and Bluetooth connectivity.
• It includes a USB Type-C connector for programming and power.
• The microcontroller runs at a clock speed of up to 240 MHz.
• It has multiple GPIO pins for input and output operations.
• It supports ADC, DAC, PWM, UART, SPI, and I2C communication.

MicroPython is a simple and small version of the Python programming language that runs on microcontrollers. It allows us to write programs in Python to control hardware such as LEDs, sensors, and displays. MicroPython makes embedded programming easier because Python is easy to read and understand compared to other languages like C or C++. Boards such as the Raspberry Pi Pico support MicroPython, allowing users to write code, upload it, and control electronic components directly. In MicroPython, we can use simple commands to turn ON or OFF an LED, read sensor values, and control devices. The code is stored inside the microcontroller, and it runs automatically when the board is powered.

Installation of Thonny:-

I opened the official Thonny IDE website and downloaded the Thonny software for my operating system. This website provides installers for Windows, Mac, and Linux.	After downloading, I ran the installer and followed the steps to install Thonny on my system.

Then I set the interpreter and port by selecting right options	Once the installation was complete, Thonny was ready to use for writing and uploading MicroPython programs to the microcontroller board.

Here is how I use esp32 and try onboard LED blinking and external LED blinking using micropython

Onboard LED Blinking

Then I use simple led blinking code.	I press on run and led turn on.

External LED Blinking

Similarly using breadboard I connect one led to pin 13.	Here it is!!!

Learning Outcomes

• Learned the basics of embedded programming and microcontroller systems.
• Worked with the Arduino Uno microcontroller
• Worked with the ESP32-WROOM microcontroller
• Learned to write programs using C++ in Arduino IDE
• Learned to write programs using MicroPython
• Understood binary number system and binary addressing
• Learned hexadecimal number system and its use in embedded programming
• Learned how to interface external components like LEDs and displays

All Program files

All codes