DEV Community: shawnkiplagat69

A Beginner's Guide to Embedded Systems: Understanding the Basics

shawnkiplagat69 — Sun, 05 Feb 2023 17:06:28 +0000

Have you ever wondered how a vending machine tells real coins and bills from fake ones? Or even how your refrigerator can be so smart as to notify you when you are low on your favourite snacks? But even more importantly, have you ever thought of really automating the tasks we do day in day out? With embedded systems nonetheless!!

So, What really is an embedded system?

Basically, embedded systems are computer systems that have a dedicated function. The one in a vending machine for instance, would be there just to weigh a coin and compare the value with that of a real coin.

In more precise terms, an embedded system is a microprocessor-based hardware computer system with integrated software (commonly termed as firmware) invented to perform a specific function as an independent or extensive system.

Well, "embedded" because they more often than not exist within a larger mechanical or electrical system and hence cannot be seen. And "system" as it encompasses multiple components interfaced together for a common purpose. And the beauty of it all? Embedded systems are designed in such a way as to hide the complex part of it, whilst giving the user a user-friendly interface for user input and feedback; as the temperature knobs on a fridge lets you set the maximum, or minimum temperature while it handles the bulk of the task under the hood.

In embedded systems, microcontrollers and microprocessors are commonly used to drive the systems. The difference?
A microcontroller is usually bare metal; encompassing the Central Processing Unit (CPU) and the peripherals on the same chip, is often good at managing input and output, and is relatively easier to setup and use. Common examples include the Arduino, the STM32 and the esp32.

A microprocessor, on the other hand, houses a more powerful CPU on a single chip that connects to external peripherals, and hence possesses a heavier processing power for complex logic operations and may even have an Operating System (OS). Common examples of such may include the Intel Core Series, the ARM microprocessor. It is also worth noting that some microprocessors even encompass microcontrollers for further processing. Fascinating, don't you think?

What does an embedded system entail?

As we have already established, an embedded system comprises multiple components interfaced together for a common purpose;

An embedded computer: This is basically a processor such as the ARM/x86/A System On Module(SOM)/A System On Chip(SOC) or even a computer for the processing of information e.g the Raspberry Pi, Arduino, ESP32 etc
A user interface: this is necessary for the display of information to the end user for feedback and interaction as well as getting user information as input via touch e.g an Organic Light Emitting Diode (OLED), Liquid Crystal Display (LCD)
A link to other systems: just as no man is an island, an embedded system also spots communication channels to other devices through communication protocols such as the Inter-Integrated Circuit (I2C), the Universal Asynchronous Receiver-Transmitter (UART), the Universal Synchronous/Asynchronous Receiver-Transmitter (USART), Controller Area Network (CAN) Bus, The Serial Peripheral Interface (SPI), etc.

The Operating System

The OS processes input data using defined commands to give a definite output data through actuators such as motors, LEDs etc

Where are embedded systems used?

Automotive industry: Nowadays, most of the vehicles in production have embedded systems; be it a music system, navigation system or even an auto-braking system. These systems serve to improve the device's functionality and enhancing the driving experience
Medicine Industry: Biomedical applications can help allow doctors remotely monitor patient's health and even offer prescription through telemedicine
Manufacturing equipment: Due to the active implementation of robots, artificial intelligence and Internet Of Things (IoT) into production processes, factories can control all types of automation systems, from online monitoring and remote control of equipment to replacing employees on assembly and production lines

and so much more...

Typical applications example?

This is a simple home automation system built using the arduino microcontroller, some relays, sensors and wires. Pretty simple yet so fascinatingly useful don't you think?

So, what is Arduino?

Arduino is an open-source hardware and software company, project and user community that designs and manufactures single-board microcontrollers and microcontroller kits for building digital devices.

What can the Arduino do?

1. Analog to Digital Conversion (ADC): By connecting sensors to an arduino microcontroller, you can easily convert analog data to digital and push the output to other boards for further processing

2. Automation: Adding sensors on the microcontroller's General Purpose Input/Output (GPIO) ports, actuators, ADCs etc to enable the collection of external parameters (data) and processing them then performing the required tasks.

In our simple smart home above for instance, we would have a simple temperature sensor on an arduino which constantly monitors the temperature of our room. Should the temperature go slightly higher than the standard room temperature, the Arduino sends a command to power on the fan and off when it drops.

What of the Raspberry Pi?

Computing for everybody

The Raspberry Pi are small, single-board computers developed in the UK by the Raspberry Pi foundation in association with Broadcom

Raspberry Pi 4 Model B

The Raspberry Pi 4 model B gives you the power of a full-blown desktop in a small form factor:

Broadcom BCM2711, Quad core Cortex-A72 (ARM v8) 64-bit SoC @ 1.5GHz
1GB, 2GB, 4GB or 8GB LPDDR4-3200 SDRAM (depending on model)
2.4 GHz and 5.0 GHz IEEE 802.11ac wireless, Bluetooth 5.0, BLE
Gigabit Ethernet
2 USB 3.0 ports; 2 USB 2.0 ports.
Raspberry Pi standard 40 pin GPIO header (fully backwards compatible with previous boards)
2 × micro-HDMI ports (up to 4kp60 supported)
2-lane MIPI DSI display port
2-lane MIPI CSI camera port
4-pole stereo audio and composite video port
H.265 (4kp60 decode), H264 (1080p60 decode, 1080p30 encode)
OpenGL ES 3.1, Vulkan 1.0
Micro-SD card slot for loading operating system and data storage
5V DC via USB-C connector (minimum 3A*)
5V DC via GPIO header (minimum 3A*)
Power over Ethernet (PoE) enabled (requires separate PoE HAT)
Operating temperature: 0 – 50 degrees C ambient

What can one do with such power?

Basically, the limit is what you set it to be

1. Software projects: Use your favourite programming language to handle various programming tasks e.g fetching camera feed, AI/ML projects

2. Automation: Adding sensors on GPIO ports, actuators and ADCs enables the collection of external parameters which can be worked on and then performing the required tasks

3. Servers/Media servers: By creating a cluster of Raspberry Pis, you can be able to host/server content on the web. It can also be used to serve media over network. Furthermore, you can make home servers for hosting own websites, media, cloud storage etc.

4. Use it as a desktop machine: Yes, you can really do that! Instead of your ordinary system unit, you can plug your Raspberry Pi onto your monitor and use it to type documents, watch movies, play games, browse, and maybe write even more code.

5. Robotics: You can build complex robotic systems to automate tasks e.g with a lighting arms

Skills you will need?

Software skills
Hardware skills
Design skills - Computer Aided Design (CAD), Printed Circuit Board (PCB) design, kiCAd

Evidently, embedded systems play a crucial role to our daily lives and are developing quickly across many sectors, including the automobile, telecommunications, and healthcare industries. The field of embedded systems will undoubtedly experience even more exciting advancements in the near future as technology continues to advance.

Remember, the limit is what you set it to be

Brought to you by the IEEE Dedan Kimathi University Student Branch

Python 101: Introduction to Python Language for Beginners

shawnkiplagat69 — Sun, 24 Apr 2022 15:47:21 +0000

Guido van Rossum designed Python, an interpreted high-level language that was launched in 1991.

Python programs end in.py and can be executed by running python file name.py from the command line.
The usage of white space rather than the more common symbols to delimit code blocks is probably its most obvious feature.
End-of-line semicolons (;) are optional in Python and are rarely used.
Python has emerged as the finest answer in a variety of fields, including online applications, data analysis, data science, machine learning, and artificial intelligence.

Python's Most Common Features:

• Simplicity: Focus on the code rather than the language's syntax.

• Open Source: A powerful language that anybody can use and modify as they see fit.
• Portability: Python code can be shared and will continue to function as intended.
• Python is embeddable and extensible, which means it can contain snippets of other languages to execute certain tasks.
• Being Interpreted: Python takes care of huge memory tasks and other CPU-intensive operations, letting you to concentrate just on coding.
• Object Orientation: Objects aid in the decomposition of complex real-world problems so that they may be coded and solved to produce solutions.

Python's applications include:

Web Development - Python is used in the development of websites using popular frameworks such as Django, Flask, and FastApi.
Embedded Applications - Because Python is based on C, it may be used to generate embedded C software for devices like the Raspberry Pi.
Game development - the process of creating interactive games with the help of popular libraries such as pygame.
Data Science and Data Visualization - Using data libraries like Matplotlib and Seaborn, data may be manipulated, represented, analyzed, and visualized. Graphical User Interface Applications (GUI) - Tkinter is used to create user interfaces.
Machine Learning and Artificial Intelligence - Computers learn algorithms based on stored data using libraries such as Pandas, Scikit-Learn, and NumPy.

Python Installation

Download the latest Python version here based on your operating system

Pycharm installation

Pycharm is a popular IDE(Integrated Development Environment) used for writing ,debugging and running python scripts.
Download Pycharm IDE to start coding

Visual studio code installation

Visual Studio Code is a Text-editor used to write and run python scripts. Download Visual Studio Code and start coding!

Building your first Python Program

"Hello World"

Start your Pycharm IDE, select a new file and save it with the .py extension. Example hello_world.py.

Write the following code in the hello_world.py file and run your first program!

print("Hello World")

The Print() function is an in-built function used to give outputs.

The following Output will be displayed:

Hello World

Variables

Variables just like hotel suites, are containers for storing data values.
Here's the syntax for assigning variables to data values.

variable_name = data_value
 For example, name = shawn

Rules for Naming Variables

A variable name must start with a letter or the underscore character.
A variable name cannot start with a number.
A variable name can only contain alpha-numeric characters and underscores (A-z, 0-9, and _ ).
Variable names are case-sensitive (name, Name and NAME are all different variables). Reminder though: Variables need not to be declared. Their data types are inferred from their assignment statement, meaning that different data types can be assigned to the same variable throughout the code. This is just what makes Python a dynamically typed language.

Keywords

Every programming language has special reserved words, or keywords, that have specific meanings and restrictions around how they should be used. Python is no different. Python keywords are the fundamental building blocks of any Python program. Examples of such keywords include False, True, and, is, class, def, return, try, as ,pass, break, continue, for, while and except.

Identifiers
Identifiers are names used to identify variables, functions,
classes, modules or other objects. Identifiers start with letter A to Z or a to z or an underscore (_) followed by zero or more letters, underscores and digits (0 to 9).

Literals
Literals are the raw data that is assigned to variables or constants while programming in Python. String literals, numeric literals, boolean literals, literal collections, and a special literal, None, are the five types of literals we have.

Data Types
A Data Type is a classification that specifies which type of value a variable has and of what type. Examples of in-built data types include

Binary Types: memoryview, bytearray, bytes.
Boolean Type: bool.
Set Types: frozenset, set.
Mapping Type: dict.
Sequence Types: range, tuple, list.
Numeric Types: complex, float, int.
Text Type: str.

Comments

Comments in Python are the lines in the code that are ignored by the interpreter during the execution of the program. Generally comments enhance the readability of the code and help other programmers interpret your code.
Types of comments include:

Single line comments

#This is a single line comment

Multi-line comments

'''
 This 
 is a multi-line 
 comment
'''

Operators

Operators are special symbols in python that carry out arithmetic and logical computation. The value that the operator operates on is called an Operand.

Types of Operators include

1. Arithmetic Operators

print(2 + 3)  # 5 (addition)
print(3 - 2)  # 1 (subtraction)
print(3 * 3)  # 9 (multiplication)
print(84 / 2)  # 42.0 (division)
print(2 ** 2)  # 4 (exponent)
print(3 % 2)  # 1 (remainder of the division)
print(11 // 2)  # 5 (floor division)

2. Comparison Operators

==  Equal to    2 == 3
!=  Not equal   2 != 3  
>   Greater than    3 > 2   
<   Less than   2 < 3   
=>  Greater than or equal to    x => y
<=  Less than or equal to    x<=y

3. Assignment Operators

=      x = 5   same as   x = 5  
+=    x += 3   same as   x = x + 3  
-=    x -= 3   same as   x = x - 3  
*=    x *= 3   same as   x = x * 3  
/=    x /= 3   same as   x = x / 3  
%=    x %= 3   same as   x = x % 3  
//=   x //= 3  same as   x = x // 3 
**=   x **= 3  same as   x = x ** 3

4. Logical Operators

and     Returns True if both statements are true    x < 5 and  x < 10   
or  Returns True if one of the statements is true   x < 5 or x < 4  
not Reverse the result, returns False if the result is true not(x < 5 and x < 10)

5. Membership Operators

in   Returns True if a sequence with the specified value is present in the object    x in y  
not in  Returns True if a sequence with the specified value is not present in the object    x not in y

Conditions and If Statements

Python statements such as if , elif and else are used when you need python to check whether a certain condition is met before a certain line of code gets executed.

#if-else ladder used in grading a students results
if grade >= 85:
  print("Grade A ")
elif grade >= 80:
  print("Grade B ")
elif grade >=70:
  print("Grade C ")
elif grade >=60:
  print("Grade D ")
else:
  print(" Sorry, you have failed terribly!! Repeat the semester")

Loops

A Loop also known as an iterative statement, is a control flow statement that is used to repeatedly execute a group of statements as long as a certain set condition is satisfied.

Python has two primitive loop commands which are while and
for loops.

- For Loop - It Iterates through the elements(list, tuple, dictionary, set, string)in the order that they appear.

#this function prints each name in the name list:
names = ["shawn", "victor", "joy","anthony"]
for all_names in names:
  print(all_names)

- While Loop - executes a set of statements as long as a condition is true.

#functoin that prints i as long as i is less than 6:
i = 1
while i < 6:
  print(i)
  i += 1

- The Break Statement
It is used to exit a loop when an external condition is triggered.

#Exits the loop whenever the value of i is equal to 3
i = 1
while i < 6:
  print(i)
  if i == 3:
    break
  i += 1

- Continue Statement
It is used to skip the execution of the current iteration and continues to the next.

#Continues to the next iteration if i is 3:
i = 0
while i < 6:
  i += 1
  if i == 3:
    continue
  print(i)

- Pass Statement
When the pass statement is executed, nothing happens, but you avoid getting an error when empty code is not allowed.
Empty code is not allowed in loops, function definitions, class definitions, or in if statements.

def info():
print("This function will get executed while the second function won't be executed")
 info()


def myfunction():
  pass
#having an empty function definition like this, would raise an error without the pass statement

Functions

A function is a block of code which only runs when it is called. You can pass data, known as parameters, into a function. A function can return data as a result.

How to create a function in Python

Use the def keyword to define a function
example

def sum():
print(2+3)

#Calling the sum function
sum()
#The output is 5

Arguments and Parameters

Data can be passed to functions through parameters inform of arguments.
Parameters are specified after the function name, inside the parentheses and are separated with a comma.
An Argument is the actual data passed to the function.

def sum(a,b):
'''a and b are the parameters  
sum is the function
def is used to define the function
'''
print(a+b)


#Calling the function
sum(2,3)
#2 and 3 are the arguments
#The output is 5

Well I guess that's all that we shall be covering in this article. I am very delighted that you had the chance to go through it. Do stay tuned though, for more Python Concepts articles so that we all learn together.