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Hello, welcome to the course. In this course, I will show you how to build a simple operating system for x86 architecture 

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,

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step by step. I will also cover the basics of the x86 architecture and low-level programming

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in order to build the projects. 

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Who is the course for? If you are a student who learned the operating system concepts 

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and wants to put them into practice.  Or you are just curious about the operating system.

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You want to know how the OS works. And you want to build a hobby OS, 

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but you don’t know how and where to start. 

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This course will teach you things you need to know to achieve the goals.  And I will take you through the process of 

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building a small working system.

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Before you take this course, you need to know the basics of x86 assembly language. 

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For example, what is move instruction, what is add instruction etc.  The basic knowledge of c language is also required

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.

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We will write the kernel in C. 

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So we will use these two languages to build the operating system.

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Now Let’s walk through the course. 

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The first section of the course is introduction to the course and operating system. The lecture must see 

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talks about how to use this course. So please don’t skip this video. The next section shows how to set up a working environment 

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to build and test the os projects.

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And then we start to build our bootloader and run it both on virtual machine and real machine.

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After we write the bootloader, we will learn how to prepare for mode switching. We switch from real mode to protected mode 

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and then jump to long mode. Our kernel is running in 64-bit mode. After we switch to 64-bit mode, 

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we will see how to handle exceptions and interrupts, how to switch between kernel mode and user mode

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.

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Then we build the kernel using c language, write a small library for the kernel code

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and implement print function to print messages on the screen which will give us valuable information.

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The assertion is used to perform checks in the kernel code and it’s very useful.

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After we load our kernel, we build the memory management module to allocate and free memory. 

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In this section, we will see how to manage the free memory using paging.

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Then we move on to process section.  We will see how to create a user process, how to use kernel services with system calls

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.

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We focus on the scheduling and how to shift between different states.

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In the next section, we will write a ps/2 keyboard driver and interact with the kernel using a console.

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The console is like a command prompt 

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where we issue a command 

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and the kernel will execute this command.

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In the section filesystem we will write a file module which reads the data in the fat16 partition

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and run user programs in the system.

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Each lecture is packed with pure information and comes with source code. You can make notes while you watch the video. 

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By the end of the course, 

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I’m confident that you will know how to write a small kernel for the x86 architecture and be able to 

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write your own operating system projects.