VISVESVARAYA TECHNOLOGICAL UNIVERSITY

Jnana Sangama, VTU Main Road, Belagum, Karnataka 590018

An Internship Report
On
“EMBEDDED SYSTEMS”
Submitted in partial fulfilment of the requirements for the award of the Degree of

BACHELOR OF ENGINEERING
In

ELECTRONICS & COMMUNICATION ENGINEERING

Submitted by
ROHAN V
1TJ21EC021

Internship carried out at

“ETECH PROWESS”

Under the Guidance

Of
Mrs. Varsha C P
Assistant Professor
Department of ECE
 T. JOHN INSTITUTE OF TECHNOLOGY
(Affiliated to Visvesvaraya Technological University)
#86/1, Gottigere, Bannerghatta Road, Bengaluru-560083

2024-2025

CERTIFICATE

This is to certify that internship work entitled “EMBEDDED SYSTEMS” carried

out by ROHAN V (1TJ21EC021) in partial fulfillment for the award of Bachelor of
Engineering in Electronics and Communication of Visvesvaraya Technological
University, Belagavi during the academic year 2024-2025. It is certified that all the
corrections/suggestions indicated for the internal assessment have been
incorporated in the report deposited in the department library. The internship report
has been approved as it satisfies the academic requirements in respect of internship
work as prescribed for the said degree.

________________ ________________ ________________

GUIDE HOD PRINCIPAL
Assistant Prof. Varsha C P Dr. Drakshayani M N Dr. H P Srinivasa

Name of the Examiner Signature with date

1.

2.
 DECLARATION

I, “ROHAN V(1TJ21EC021)” student of T. John Institute of Technology, Bengaluru,

hereby declare that the dissertation entitled, “EMBEDDED SYSTEMS”, which has been
submitted by me as partial fulfilment for the final year semester examination of Engineering
degree from Visvesvaraya Technological University, Belgaum, is an authentic record of my
own work carried out by me during final year at ETECH PROWESS, under the supervision
of my internal supervisor Asst. Prof. Varsha C P ,TJIT, Bengaluru and external supervisor
Mr. KRISHNAN

I further undertake that the matter embodied in the dissertation has not been submitted previously
for the award of any degree or diploma by me to any institution.

ROHAN V

1TJ21EC021

Place: Bengaluru.
Date:
 ACKNOWLEDGEMENT

The satisfaction and euphoria that accompanies the successful completion of any task would be
incomplete without mentioning the people who made it possible, whose constant guidance and
encouragement crowned my efforts with success.

I thank our Principal, Dr. H P. SRINIVASA and Head of the Department, Dr. Drakshayani M
N , Department of Electronics & Communication Engineering who has given us confidence to
believe in ourselves and complete the Internship.

Guidance and deadlines play a very important role in successful completion of the internship
report on time. I convey my gratitude to my internal supervisor, Asst Prof. Varsha C P and
external supervisor Mr. KRISHNAN who helped me carry out my internship work.

ROHAN V
1TJ21EC021
 ACKNOWLEDGEMENT

I hereby express my happiness for completing “INTERNSHIP” Training successfully for the
period of one month. I generally thank all the employees for giving me an opportunity to learn
many important features of training. I extend my special thanks and gratitude to Mr.
KRISHNAN for guidance given in spite of a busy work schedule and made course very
interesting for which act of kindness remain ever grateful. I also thank department of ECE and
gratitude to my internal guide Asst. Prof. VARSHA C P for guidance and support for
completing the report on time.

Finally, I hope this course will help me in building my career of engineering with the aid of
equipment provided by your factory in a cordial atmosphere.

ROHAN V

1TJ21EC021
 ABSTRACT

This report provides an in-depth analysis of Embedded Systems, focusing on microcontrollers,

sensors, communication protocols, motor control, and AI integration. It covers STM32
microcontrollers, UART, SPI, I2C, and USB communication, along with real-time operating
systems (RTOS) for efficient task management.

Additionally, the report explores servo motors (SG90, MG90), WS2812 programmable LEDs
(Neopixel), and memory management techniques for optimizing embedded applications. It also
examines computer vision applications using OpenCV (cv2) and MediaPipe, highlighting real-
time object tracking and gesture recognition.

Lastly, development tools like STM32CubeIDE and Arduino IDE, along with version control
strategies using Git, are discussed. This report serves as a valuable resource for understanding
the latest advancements in embedded systems.
OFFER LETTER
 TABLE OF CONTENTS

CHAPTER No. CONTENT PAGE No.

Abstract
Certificate
Chapter 1 Etech Prowess overview 10
1.1 Introduction 10
Chapter 2 Embedded Systems 11-12
2.1 Introduction 11
2.2 Characteristeics of embedded systems 11
Chapter 3 Microcontrollers and embedded development 13-17
3.1 Microcontrollers 13
3.2 STM32 14
3.3 ESP32 16
Chapter 4 Programming embedded systems 17-21
4.1 Introduction 18
4.2 Programming languages used in embedded systems 18
4.3 Data types in embedded C 19
4.4 Memory management in embedded systems 19
4.5 Interrupts in embedded systems 20
4.6 Timers in embedded system 20
Chapter 5 Communication protocols 22-25
5.1 UART 22
5.2 SPI 23
5.3 I2C 24
5.4 USB 25
Chapter 6 Motors 26-30
6.1 DC motor 26
6.2 Stepper motor 27
6.3 Servo motor 28
6.4 Rotrics DexArm- an all-in-one robotic arm 28
Chapter 7 AI in embedded systems 31-32
7.1 openCV(cv2) 31
7.2 Mediapipe- AI framework for real-time perception 31
7.3 Ultralytics YOLO- real-time object detection 32
Conclusion 33
EMBEDDED SYSTEMS

LIST OF FIGURES
FIGURE No. FIGURE NAME PAGE No.

3.1 STM32 microcontroller 15

3.2 ESP32 microcontroller 17
5.1 UART protocol 23
5.2 SPI protocol 23
5.3 I2C protocol 24
5.4 USB protocol 25
6.1 DC motor 26
6.2 Stepper motor 27
6.3 Servo motor 28
6.4 Rotrics DexArm 30

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CHAPTER 1
ETECT PROWESS OVERVIEW

1.1 Introduction

Etech Prowess Private Limited, established on December 6, 2022, is a Bengaluru-based

company specializing in education and training within the technology sector.

Founded by directors Vasu Jayarama Kammachi and Bangalore Gopala Krishna Srikanth,
Etech Prowess focuses on delivering courses in embedded systems, Internet of Things (IoT),
artificial intelligence (AI), machine learning (ML), and Windows device drivers. Their
training methodology emphasizes comprehensive, project-specific, and job-oriented
approaches.

The company offers a range of courses tailored for different audiences, including students,
freshers, professionals, and corporate clients. Notable programs include VLSI Physical
Design, VLSI Design Verification, Semiconductor Embedded Engineering, Front-End
Development, and Full-Stack Web Development. These courses combine classroom training
with real-time projects to enhance practical skills.

Etech Prowess has established partnerships with various companies for placements, with
recent hires at organizations like UST Global, AMD, and Mirafra Technologies. Their
commitment to quality education was recognized when they received the "Most Promising
Start-Up" award at the 38th International Conference on VLSI Design in 2025.

In summary, Etech Prowess Private Limited is a young and dynamic company in Bengaluru,
dedicated to providing specialized training in advanced technological domains, with a focus
on practical, industry-relevant education.

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EMBEDDED SYSTEMS

CHAPTER 2
EMBEDDED SYSTEMS

2.1 Introduction

Embedded systems are specialized computing devices that are designed to perform specific
tasks within a larger system. Unlike general-purpose computers, embedded systems are
optimized for particular applications and are often integrated directly into the devices they
control. These systems may be simple or complex, but they all consist of four main
components:

1. Microcontroller/Microprocessor: This is the central processing unit (CPU) of the

embedded system, responsible for executing instructions and processing data.
2. Memory: Embedded systems typically have memory (RAM, ROM, EEPROM, etc.)
to store both the program code (software) and the data they work with.
3. Input/Output Peripherals: These components allow the system to interact with its
environment. Input devices might include sensors or user interfaces, while output
devices might include displays or actuators.
4. Embedded Software: The software running on the system is designed specifically to
perform the embedded tasks. This software may be embedded in the system's
firmware or stored in non-volatile memory.

Embedded systems are essential in a wide range of applications, from controlling household
appliances to monitoring industrial machinery, and even managing critical functions in
healthcare and automotive systems. They are designed for reliability, efficiency, and cost-
effectiveness.

2.2 Characteristics of Embedded Systems

1. Real-time Operation:

 Embedded systems often operate in real-time, meaning they need to respond to inputs
or events within strict time constraints. Real-time systems are crucial in applications
where timing is critical, such as in automotive control systems, medical devices, or
robotics.
 The system must guarantee that it responds to events within a predetermined time,
ensuring the system's overall functionality is maintained. For example, a car's anti-
lock braking system (ABS) must react immediately to changes in road conditions or
pressure from the brake pedal.

2. Specific Functionality:
 Embedded systems are designed to carry out a specific set of functions and are not
general-purpose like personal computers. They are typically optimized for one or a

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small set of tasks, which allows them to be highly efficient and reliable for those
tasks.
 For example, the embedded system in a microwave oven is programmed to perform
tasks like heating food, while a smart thermostat's embedded system is programmed
to control room temperature based on sensors.

3. Resource Constraints:

 Many embedded systems operate with limited resources, including memory,

processing power, and energy. Due to the nature of embedded systems, they are
designed to be highly efficient in terms of both hardware and software. Their compact
form factor often results in trade-offs regarding the power and resources they can
utilize.
 For example, in wearable health devices, the system may need to perform complex
health monitoring functions with limited memory and processing capacity, while
maintaining low power consumption to extend battery life.

4. High Reliability:

 Reliability is one of the most critical aspects of embedded systems, especially in

industries where failure can have severe consequences. These systems need to operate
continuously without failure, making them highly dependable.
 Applications such as medical devices (e.g., pacemakers), aerospace systems, and
nuclear power plants depend on embedded systems for safety and precision. In these
scenarios, even a minor malfunction could be catastrophic, so the system must be
rigorously designed for fault tolerance, error handling, and system recovery.

Other Considerations

 Cost-effectiveness: Embedded systems are typically designed to be cost-efficient, which

is a key factor in their widespread use. By focusing on a specific function, designers can
optimize the system's cost and ensure that it meets the required performance standards
without excessive overhead.
 Long Lifecycle: Many embedded systems are designed to operate for many years. For
example, embedded systems in automotive safety equipment or industrial robots need to
be highly durable and support long-term maintenance cycles.
 Low Power Consumption: Many embedded systems are battery-operated, requiring low
power consumption to ensure longevity. For example, smartwatches, sensor nodes, and
portable medical devices must operate efficiently on limited power sources.

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EMBEDDED SYSTEMS

CHAPTER 3

MICROCONTROLLERS AND EMBEDDED DEVELOPMENT

3.1 Microcontrollers

A microcontroller (MCU) is a compact integrated circuit (IC) designed to control embedded

devices. Unlike general-purpose processors, microcontrollers are optimized for specific tasks
and integrate a CPU, memory, input/output (I/O) interfaces, and communication peripherals
into a single chip. These devices are widely used in consumer electronics, automotive
systems, industrial automation, healthcare, and IoT applications.

Popular Microcontroller Families

Microcontrollers are classified based on their architecture, processing power, and power
efficiency. Some of the most widely used microcontroller families include:

1. STM32 (by STMicroelectronics)

 Based on ARM Cortex-M cores, offering high performance, low power consumption,
and a rich set of peripherals.
 Used in IoT applications, robotics, industrial automation, and smart home devices.
 Supports multiple development tools, including STM32CubeIDE and Keil.

2. AVR (by Microchip Technology)

 Known for its 8-bit RISC architecture, making it power-efficient and simple to program.
 Found in Arduino boards, home automation, and small-scale embedded applications.
 Provides essential peripherals such as timers, GPIO, ADC, and communication protocols
(UART, SPI, I2C).

3. PIC (by Microchip Technology)

 Available in 8-bit, 16-bit, and 32-bit variants, offering flexibility for different
applications.
 Used in automotive, industrial control, and sensor-based systems.
 Features low-power modes and reliable performance for battery-operated devices.

4. ESP32 (by Espressif Systems)

 A high-performance, low-power microcontroller with built-in Wi-Fi and Bluetooth

capabilities.
 Widely used in IoT applications, smart home automation, and wearable devices.
 Supports multiple communication interfaces, including UART, SPI, I2C, and Ethernet.

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 Features a dual-core Tensilica Xtensa LX6 processor, making it more powerful than
many traditional microcontrollers.
 Compatible with Arduino IDE, ESP-IDF (Espressif IoT Development Framework), and
MicroPython.

5. ARM Cortex-M Series (by ARM Holdings)

 A widely adopted microcontroller architecture used by manufacturers like

STMicroelectronics, NXP, Texas Instruments, and Nordic Semiconductor.
 Designed for high-performance computing with real-time processing capabilities.
 Commonly used in IoT, AI-driven applications, medical devices, and industrial
automation.

3.2 STM32 Microcontrollers

The STM32 family, developed by STMicroelectronics, is a popular choice for embedded

system designers due to its scalability, performance, and rich peripheral set. These
microcontrollers are based on the ARM Cortex-M architecture, providing a balance between
processing power and power efficiency.

Key Features of STM32 Microcontrollers

1. GPIO (General-Purpose Input/Output)

 Used for interfacing with external components such as LEDs, buttons, sensors,
motors, and displays.
 Supports various modes like input, output, alternate function, and analog.
 Features interrupt capabilities for real-time event handling.

2. Timers and Counters

 Used for measuring time intervals, generating precise delays, and event counting.
 Supports Pulse Width Modulation (PWM), which is essential for motor control, LED
dimming, and communication protocols.
 Can be used for capturing external events, such as frequency or signal measurement.

3. Communication peripherals

STM32 microcontrollers support multiple communication protocols, enabling connectivity

with sensors, memory devices, and other microcontrollers:

 UART (Universal Asynchronous Receiver-Transmitter) - Serial communication with

computers, GPS modules, and Bluetooth devices.
 SPI (Serial Peripheral Interface) - High-speed communication with displays, flash
memory, and sensors.

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EMBEDDED SYSTEMS

 I2C (Inter-Integrated Circuit) - Used for low-speed communication with multiple

devices, such as temperature sensors and EEPROMs.
 USB (Universal Serial Bus) - Supports USB device and host functionality, enabling
data transfer and device communication.
 CAN (Controller Area Network) - Commonly used in automotive and industrial
applications for real-time communication between multiple devices.

4. ADC & DAC (Analog-to-Digital and Digital-to-Analog Converters)

 ADC (Analog-to-Digital Converter) - Converts analog sensor signals (e.g.,

temperature, pressure, light intensity) into digital values.
 DAC (Digital-to-Analog Converter) - Converts digital signals into analog outputs,
useful for audio applications and signal generation.

Why Choose STM32?

STM32 microcontrollers are highly versatile and come in different series, such as:

 STM32F Series - General-purpose microcontrollers with high performance.

 STM32L Series - Low-power MCUs for battery-operated applications.
 STM32H Series - High-performance MCUs for demanding applications.
 STM32G Series - General-purpose, energy-efficient MCUs for cost-sensitive designs.

Advantages of STM32 MCUs

 High Processing Power - ARM Cortex-M cores enable efficient execution of complex
tasks.
 Rich Peripheral Set - Supports advanced communication and control features.
 Low Power Consumption - Suitable for IoT and battery-powered applications.
 Strong Development Support - STM32CubeIDE, HAL (Hardware Abstraction Layer),
and community support enhance development.

Fig 3.1: STM32F401

3.3 ESP32 Microcontroller

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EMBEDDED SYSTEMS

The ESP32, developed by Espressif Systems, is a powerful Wi-Fi and Bluetooth-enabled

microcontroller designed for IoT applications and real-time processing.

Key Features of ESP32

1. Dual-Core Processor

 Based on the Tensilica Xtensa LX6 architecture.

 Supports multitasking and real-time data processing.

2. Built-in Wi-Fi & Bluetooth

 Supports Wi-Fi (802.11 b/g/n) and Bluetooth 4.2 (including BLE) for wireless
communication.
 Used in smart home automation, wearable technology, and industrial IoT
applications.

3. Low Power Modes

 Features Deep Sleep and Light Sleep modes, making it ideal for battery-powered
applications.

4. Rich Peripherals & Connectivity

 Supports UART, SPI, I2C, I2S, Ethernet, and SDIO.

 Includes capacitive touch sensors, enabling gesture-based control.

5. Strong Development Ecosystem

 Programmable using Arduino IDE, ESP-IDF, MicroPython, and PlatformIO.\

Use Cases

 Deep Sleep Mode - Ideal for battery-operated IoT devices like weather stations and
remote sensors.
 Hibernation Mode - Used in applications where the device needs to wake up periodically
(e.g., smart meters).

Programming Environments

 Arduino IDE - Beginner-friendly environment with support for ESP32 libraries.

 ESP-IDF (Espressif IoT Development Framework) - Official development framework for
ESP32, offering advanced features and performance tuning.
 MicroPython - Allows developers to use Python for embedded applications.

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EMBEDDED SYSTEMS

 PlatformIO - A modern, powerful, and flexible IoT development platform supporting

multiple languages.

Fig 3.2: ESP32

CHAPTER 4

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EMBEDDED SYSTEMS

PROGRAMMING EMBEDDED SYSTEMS

4.1 Introduction

Embedded systems programming involves writing software that directly interacts with hardware
to perform dedicated functions. Unlike general-purpose computing, embedded systems operate
with limited resources, real-time constraints, and specific hardware requirements. Programming
in embedded systems requires an understanding of low-level programming, memory
management, real-time constraints, and hardware-software interfacing.

Embedded systems consist of microcontrollers or microprocessors that run software to control

various peripherals and execute predefined tasks. These systems are widely used in automotive,
industrial automation, healthcare, consumer electronics, and IoT applications.

Embedded programming typically involves low-level coding using languages like C and C++ for
efficient hardware control, and sometimes assembly language for performance optimization.

4.2 Programming Languages Used in Embedded Systems

1. C Language in Embedded Systems

C is the most widely used programming language in embedded systems because of its
efficiency, portability, and direct hardware access. Features of C that make it suitable for
embedded programming include:

 Direct access to memory addresses and hardware registers.

 Efficient handling of pointers for managing hardware interactions.
 Low-level bitwise operations for controlling devices.

2. C++ for Embedded Development

C++ extends C by offering object-oriented programming (OOP), which helps in managing

complex projects. It includes:

 Encapsulation for better code modularity.

 Abstraction and inheritance for reusable code.
 Template programming to optimize resource usage.

However, C++ introduces higher memory and processing overhead, so it is used selectively in
embedded systems with sufficient resources.

Other Languages Used

 Assembly Language: Used for performance-critical tasks where direct hardware control
is necessary.

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EMBEDDED SYSTEMS

 Python and MicroPython: Used in higher-level embedded applications and prototyping.

 Rust: Gaining popularity due to memory safety features in embedded programming.

4.3 Data Types in Embedded C

Embedded C uses various data types for handling variables and memory efficiently.
Choosing the right data type is crucial because embedded systems often have limited
memory and processing power.

Basic Data Types

1. Char :8 bits (1 byte) - Stores characters or small integers

2. int :16 or 32 bits - Stores integer values (size depends on architecture).

3. float :32 bits - Stores decimal numbers with single precision.

4. double :64 bits - Stores decimal numbers with double precision

Using the volatile Keyword

 The volatile keyword prevents the compiler from optimizing variables that can change
unexpectedly (e.g., hardware registers, shared memory, interrupt-driven variables).
 Without volatile, the compiler might optimize out a variable because it assumes its value
does not change.

Use Cases for volatile:

 Reading sensor data (e.g., temperature, pressure).

 Shared memory between main code and Interrupt Service Routine (ISR).
 Memory-mapped peripheral registers (e.g., GPIO, UART).

4.4 Memory Management in Embedded Systems

Memory management is a crucial aspect of embedded programming, as embedded systems

have limited RAM. Efficient memory usage ensures better performance and stability.

Stack vs. Heap Memory

Embedded systems use stack and heap memory for different purposes.

1.Stack

 It is used for function calls, local variables, and return addresses

 The stack is fast but has a fixed size determined at compile-time.
 If too many function calls or large local variables are used, stack overflow may
occur.

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EMBEDDED SYSTEMS

2.Heap

 It is used for dynamic memory allocation.

 Heap memory is flexible but can lead to memory fragmentation and slower
performance if not managed properly.

Memory Optimization Techniques

 Avoid excessive recursion (reduces stack overflow risk).

 Use static/global variables wisely (minimizes stack usage).
 Prefer static over dynamic memory allocation (malloc).

Another important consideration is structure padding and alignment. Some processors

require data to be aligned to specific memory addresses for efficient access. If a structure
contains mixed data types, the compiler may insert padding to align data correctly.

4.5 Interrupts in Embedded Systems

Interrupts allow a microcontroller to respond immediately to external/internal events without

continuously polling for updates.

Interrupt Service Routine (ISR)

 An ISR is a special function that executes when an interrupt occurs.

 It must be short and efficient to minimize delays in program execution.

Best Practices for ISRs

1. Keep ISRs short and efficient (avoid delays).

2. Use volatile for shared variables modified inside ISR.
3. Do not use functions like printf() or malloc() inside an ISR (they are time-consuming).

4.6 Timers in Embedded Systems

Timers are hardware peripherals that allow precise time measurement and scheduling in
embedded systems. They are used for generating delays, pulse-width modulation (PWM)
signals, and event counting.

Common Timer Functions:

1. Delays & Scheduling - Generate precise time delays.

2. Pulse Width Modulation (PWM) - Control LED brightness, motor speed.

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EMBEDDED SYSTEMS

3. Event Counting - Measure frequency of external signals.

4. Triggering periodic interrupts to execute tasks at fixed intervals

CHAPTER 5
COMMUNICATION PROTOCOLS

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EMBEDDED SYSTEMS

Efficient and reliable data exchange between embedded devices, sensors, and peripherals is
achieved through various wired and wireless communication protocols. These protocols enable
devices to send and receive data efficiently while considering factors like speed, power
consumption, and complexity.

The four main wired communication protocols used in embedded systems are:

 UART (Universal Asynchronous Receiver/Transmitter)

 SPI (Serial Peripheral Interface)
 I2C (Inter-Integrated Circuit)
 USB (Universal Serial Bus)

5.1 UART (Universal Asynchronous Receiver/Transmitter)

UART is a serial communication protocol used for asynchronous data transmission between
microcontrollers and external devices like sensors, GPS modules, Bluetooth modules, and
computers. Unlike synchronous communication protocols like SPI and I2C, UART does not
require a clock signal, making it simple and widely used in embedded applications.

How UART Works

UART communication involves two main signals:

 TX (Transmit): Sends data from one device to another.

 RX (Receive): Receives data from another device.

Each UART device has its own clock, and both sender and receiver must be configured with
the same baud rate (e.g., 9600, 115200 bps).

Key Features of UART

 Asynchronous communication: No clock signal is required.

 Full-duplex communication: Data can be sent and received simultaneously.
 Simple and widely supported in microcontrollers and embedded devices.

Common Applications

 Serial debugging using a PC’s serial port.

 Communication with Bluetooth modules (HC-05, HC-06).
 Interfacing GPS modules (e.g., NEO-6M).

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EMBEDDED SYSTEMS

Fig 5.1: UART protocol

5.2 SPI (Serial Peripheral Interface)

SPI is a synchronous communication protocol designed for high-speed data exchange

between a master device (e.g., microcontroller) and one or more slave devices (e.g., sensors,
memory chips, displays). It is commonly used in applications requiring fast data transfer
rates.

How SPI Works

SPI uses four main signals:
 SCLK (Serial Clock): Synchronizes data transmission between master and slave.
 MOSI (Master Out, Slave In): Transfers data from master to slave.
 MISO (Master In, Slave Out): Transfers data from slave to master.
 SS (Slave Select): Selects the specific slave device to communicate with.

Key Features of SPI

 Full-duplex communication: Data can be sent and received at the same time.
 High-speed data transfer: Faster than I2C and UART.
 Supports multiple slave devices using different SS lines.

Common Applications

 Interfacing with flash memory (e.g., SD cards, EEPROMs).

 Controlling displays (OLED, TFT, LCD).
 Communicating with high-speed sensors (gyroscopes, accelerometers).

Fig 5.2: SPI protocol

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EMBEDDED SYSTEMS

5.3 I2C (Inter-Integrated Circuit)

I2C is a two-wire synchronous communication protocol used for low-speed, short-distance

communication between multiple devices. It is widely used in applications where multiple
sensors or peripherals need to communicate with a microcontroller using minimal pins.

How I2C Works

I2C uses only two main signals:

 SCL (Serial Clock Line): Synchronizes data transfer between master and slave.
 SDA (Serial Data Line): Transfers data between master and slave.

Each slave device has a unique address, allowing multiple devices to communicate on the
same bus without additional chip select lines.

Key Features of I2C

 Supports multiple devices on a single bus.

 Only two wires required for communication.
 Uses addressing to select slave devices.

Common Applications

 Interfacing EEPROMs (24CXX series).

 Real-Time Clock (RTC) modules (DS1307, DS3231).
 LCD displays and touch controllers.

Fig 5.3: I2C protocol

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EMBEDDED SYSTEMS

5.4 USB (Universal Serial Bus) Communication

USB is a widely used protocol for high-speed data exchange between embedded systems and
computers. Unlike UART, SPI, and I2C, USB supports plug-and-play functionality, enabling
embedded devices to communicate with PCs, external storage, and other peripherals.

USB Configurations in Embedded Systems

 USB Host: The embedded system acts as a controller, managing connected USB devices
(e.g., a microcontroller controlling a USB flash drive).
 USB Device: The embedded system acts as a peripheral (e.g., a microcontroller
appearing as a virtual COM port on a PC).

Key Features of USB

 High-speed data transfer (USB 2.0, USB 3.0).

 Supports multiple device types (keyboard, mouse, storage, serial communication).
 Plug-and-play with automatic device recognition.

Common Applications

 Data logging devices (storing sensor data to a USB drive).

 Firmware updates via USB.
 USB-to-serial communication (virtual COM ports).

Fig 5.4: USB protocol

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EMBEDDED SYSTEMS

CHAPTER 6

MOTORS
Motor control is a crucial aspect of robotics, industrial automation, automotive systems, and
consumer electronics. Different types of motors are used based on the required precision, torque,
speed, and control complexity.

The three most commonly used motors in embedded systems are:

 DC Motors – Used for continuous rotation with speed control.

 Stepper Motors – Used for precise positioning applications.
 Servo Motors – Used for precise angular control.

6.1 DC Motors

A DC (Direct Current) motor converts electrical energy into mechanical motion. These
motors are commonly used in robotics, conveyor belts, and electric vehicles due to their
ability to provide smooth, continuous rotation.

How DC Motors Work

A DC motor consists of a rotor (armature) and a stator. When current flows through the
motor’s windings, a magnetic field is generated, causing the rotor to spin. The speed of a DC
motor is controlled by varying the applied voltage using Pulse Width Modulation (PWM).

PWM Speed Control

 PWM (Pulse Width Modulation) is used to regulate the speed of a DC motor by adjusting
the duty cycle of the control signal.
 A higher duty cycle increases speed, while a lower duty cycle decreases it.

Common Motor Driver ICs for DC Motors

 L298N – Dual H-Bridge driver, suitable for controlling two DC motors.

 L293D – Another popular H-Bridge IC, capable of handling moderate currents.

Fig 6.1: DC motor

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6.2 Stepper Motors

Stepper motors are precisely controlled motors that rotate in discrete steps, making them
ideal for applications requiring precise positioning. They are widely used in CNC machines,
3D printers, and robotic arms.

How Stepper Motors Work

A stepper motor consists of multiple coils (phases) that are energized in a specific sequence
to move the rotor step by step. The key advantage is that the motor's position can be
controlled without a feedback system.

Types of Stepper Motors

 Unipolar Stepper Motors – Easier to control but less efficient.

 Bipolar Stepper Motors – Require H-Bridge control but offer higher torque.

Stepper Motor Drivers

Microcontrollers cannot directly drive stepper motors due to their high power requirements.
Common stepper motor driver ICs include:

 ULN2003 – Used for unipolar stepper motors.

 A4988 / DRV8825 – Used for bipolar stepper motors with microstepping.

Stepper Motor Control Methods

 Full-step mode – The motor moves one full step per pulse.
 Half-step mode – The motor moves half a step for finer resolution.
 Microstepping – The motor moves in very small steps for smooth motion.

Fig 6.2: Stepper motor

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6.3 Servo Motors (SG90, MG90S)

Servo motors are designed for precise angular movement, making them ideal for robotic
arms, RC cars, drones, and automation systems. Unlike DC motors, servo motors do not
rotate continuously but instead hold a specific angle.

How Servo Motors Work

A servo motor consists of:

 A DC motor – Provides rotation.

 A gear system – Reduces speed and increases torque.
 A control circuit – Adjusts the motor’s position based on PWM signals.

Servo motors require a PWM signal to maintain a specific position. The duty cycle of the PWM
signal determines the motor’s angle.

Controlling Servo Motors with PWM

 A PWM signal with a pulse width of 1ms moves the servo to 0°.
 A pulse width of 1.5ms moves it to 90°.
 A pulse width of 2ms moves it to 180°.

Fig 6.3: Servo motor

6.4 Rotrics DexArm – An All-in-One Robotic Arm

The Rotrics DexArm is a versatile, modular robotic arm designed for multiple applications,
including pick-and-place operations, 3D printing, laser engraving, and drawing. It is widely
used in education, automation, and creative fields due to its high precision, user-friendly
software, and customizable toolheads.

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Key Features

 Multi-functional – Supports 3D printing, laser engraving, pen drawing, and pick-and-

place.
 Modular Design – Easy swapping of different toolheads.
 High Precision – 0.05mm repeatability, ensuring smooth and accurate movements.
 Easy Programming – Supports G-code, Python, Blockly (visual programming), and
SDKs.
 Connectivity Options – USB, Bluetooth, Wi-Fi for remote control.
 Smart Safety Features – Built-in safety mechanisms for stable operations.

Technical Specifications
Feature Specification

Working Area 220mm (X-axis), 220mm (Y-axis), 250mm (Z-axis)

Repeatability ±0.05mm

Max Payload 500g

Actuators Stepper Motors with Encoders

Connectivity USB, Bluetooth, Wi-Fi

Software Support Rotrics Studio, Python, Blockly, G-code

Power Supply 12V/5A DC

Rotrics DexArm Toolheads and Applications

1. Pick and Place (Robotic Gripper)

 Used in automation, warehouse sorting, and assembly lines.

 The robotic arm can pick up objects and place them in predefined locations.
 Controlled via pre-programmed motion sequences or AI-powered object recognition.

2. 3D Printing (FDM Extruder)

 Converts the robotic arm into a 3D printer for prototyping and manufacturing.

 Supports PLA, ABS, TPU filaments for printing objects layer by layer.
 Uses G-code for precise motion control.

3. Laser Engraving & Cutting

 Can engrave and cut on wood, acrylic, leather, and paper.

 Supports laser power levels up to 2.5W for different materials.

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 Used for customized designs, signage, and artistic engravings.

4. Pen Drawing & Writing

 The pen holder allows the DexArm to write text, sketch, and draw.
 Ideal for art, calligraphy, and automated note-writing applications.
 Works with SVG files and vector-based designs.

Software & Programming

1.Rotrics Studio (Official Software)

 Drag-and-Drop Interface for beginners.

 Advanced G-code Programming for experts.
 Built-in Templates for engraving, printing, and drawing.

2.Programming Options

 Python API for advanced automation.

 G-code Support for CNC and 3D printing.
 Blockly (Visual Coding) for beginners.

Use Cases
 Education & Research – Used in robotics courses and STEM education.

 Manufacturing & Automation – Ideal for pick-and-place operations.

 Creative Design – Used for engraving, drawing, and 3D modeling.

 Prototyping & Development – Helps in rapid prototyping of designs.

Fig 6.4: Rotrics DexArm

CHAPTER 7

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AI IN EMBEDDED SYSTEMS
Artificial Intelligence (AI) is revolutionizing embedded systems by enabling real-time image
processing, object detection, and machine learning (ML) applications on low-power devices.
AI-powered embedded systems are widely used in robotics, smart surveillance, industrial
automation, and IoT applications.

7.1 OpenCV (cv2) – Open-Source Computer Vision Library

OpenCV (Open Source Computer Vision Library) is a powerful open-source library for
image processing, computer vision, and machine learning. It is widely used in embedded
systems for object detection, facial recognition, and real-time video analysis.

 Lightweight and optimized for real-time processing

 Compatible with Python, C++, and embedded platforms like Raspberry Pi, ESP32, and
NVIDIA Jetson

Key Features of OpenCV in Embedded Systems

 Image Processing – Edge detection, color filtering, noise reduction

 Object Detection – Identifying and tracking objects in real-time
 Face Recognition – Used in security systems and biometric authentication
 Gesture Recognition – Hand tracking for touchless interfaces
 Augmented Reality (AR) – Combining virtual objects with real-world environments

Applications of OpenCV in Embedded Systems

 Smart CCTV systems – Real-time face recognition for security

 Autonomous robots – Object tracking for navigation
 Medical imaging – Analyzing X-rays and MRIs
 Industrial automation – Quality control through image recognition

7.2 MediaPipe – AI Framework for Real-Time Perception

MediaPipe is a Google-developed open-source framework designed for real-time AI-based

perception applications. It provides pre-trained AI models for hand tracking, face detection,
and gesture recognition.

 Lightweight and optimized for embedded platforms (Raspberry Pi, Edge TPU, Jetson
Nano, etc.)
 Supports Python and C++ for easy implementation
 Works on CPUs and GPUs, enabling efficient AI processing

Key Features of MediaPipe

 Hand Tracking – Detects and tracks hand movements for gesture recognition
 Face Detection & Recognition – Identifies faces in real-time

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 Pose Estimation – Tracks body movements for fitness applications

 Object Detection – Recognizes objects in images and video streams
 Speech Recognition – Processes audio for smart assistants

Applications of MediaPipe in Embedded Systems

 Smart home automation – Gesture-controlled devices

 Health monitoring – Pose estimation for physiotherapy
 Robotics – AI-driven object interaction
 Augmented Reality (AR) – Face and hand tracking for virtual experiences

7.3 Ultralytics YOLO (You Only Look Once) – Real-Time Object Detection

Ultralytics YOLO is a state-of-the-art real-time object detection model that enables

embedded systems to identify and track objects efficiently. It is optimized for edge devices
like Raspberry Pi, NVIDIA Jetson Nano, and Coral Edge TPU.

 Faster than traditional CNN-based object detection models

 High accuracy and low latency for real-time AI applications
 Supports PyTorch and TensorFlow for easy deployment

How YOLO Works in Embedded Systems

 Single-pass detection – Identifies multiple objects in a single image pass.

 Grid-based approach – Splits images into grids and predicts objects in each section.
 Lightweight models – YOLOv5 and YOLOv8 optimized for edge AI.

Applications of YOLO in Embedded Systems

 Autonomous vehicles – Real-time obstacle detection

 Smart surveillance – AI-based security cameras
 Robotic vision – Object detection for pick-and-place robots
 Industrial quality control – Detecting defects in manufacturing

CONCLUSION
In conclusion, this report offers a comprehensive exploration of embedded systems, delving
into critical components such as microcontrollers, communication protocols (UART, SPI,
I2C, USB) and motor control, alongside advanced integrations like AI and computer vision

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using OpenCV and MediaPipe. The inclusion of real-time operating systems (RTOS) and
memory management techniques underscores the importance of efficient task handling and
resource optimization in embedded applications. Furthermore, the report highlights practical
applications, such as WS2812 programmable LEDs and real-time object tracking,
demonstrating the versatility of embedded systems in modern technology. By leveraging
development tools like STM32CubeIDE, Arduino IDE, the study emphasizes the
significance of robust development practices in advancing embedded system design.

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