bemxOS

bemxOS (pronounced "bemsh-OS" but people pronounce it wrongly as "bem-x-OS" and other people get to be pedantic and correct those people) is a little operating system created by me (bemxio!), just for learning OS development.

Based on this cool tutorial. If you want to make your own OS, you should follow that tutorial too!

I plan to add network support and all of the other cool stuff later on, don't expect it soon though. For now, it will probably just have a few basic commands with a basic filesystem as well.

Running

Before trying to run anything, make sure to obtain an image file of the system.

You can either get it from here, or you can just compile it yourself.

VirtualBox

1. Open VirtualBox and press the New button with a blue icon.
2. Name the virtual machine however you want, set the type to Other and the version to Other/Unknown.
3. After pressing Next, choose Do not add a virtual hard disk. On the warning message box, press Continue.
4. Select the virtual machine from the list, and press Settings.
5. Go to the Storage window, select the Controller: IDE controller and delete it using the small buttons at the bottom of the list.
6. Add a new controller and choose I82078 (Floppy).
7. Select the Controller: Floppy controller and press the floppy disk icon with a plus on the highlighted controller.
8. In the pop-up window, press Leave Empty.
9. Click on the Empty button on the list.
10. Click the floppy disk next to the Floppy Drive 0 text, and from the dropdown menu, select Choose a disk file....
11. Select the image file you downloaded (or compiled yourself) out from GitHub and confirm the file choice.
12. Press OK to save all of the settings.

After doing all of the setup, bemxOS should boot up correctly after pressing the Start button.

QEMU

Just simply run the image.img file within the command line with the following command:

qemu-system-i386 -fda image.img

Building

You will need some prerequisites before you start compiling the system:

• a Linux host system (if you are on Windows, WSL will do the job)
• a GCC cross-compiler (feel free to follow this tutorial for steps on how to compile one yourself)
• (optionally) QEMU, for testing the system
• (optionally) GCC, for debugging it

1. Export some global environment variables:

   • CC_PATH, that points to the directory path of your cross-compiler.
   • (optionally) QEMU_PATH, that points to the QEMU directory. (for Windows peeps, install QEMU on Windows and point to it in WSL, where /mnt/c/ is C:\)
   • (optionally) GDB_PATH, that points to the GDB executable. (for Windows peeps, it's the same as with QEMU)

2. Clone the repository using git, and use cd to change the current directory.

3. Just run the make command, and it should work!

It should produce a bemxOS.bin file at the end, that you can launch with QEMU.

If you want to clean all of the mess the compilers made, you can run make clean to quickly get rid of all of the files.

Debugging

If you set up the QEMU_PATH and GDB_PATH environment variables, you can use make debug to compile the code and run it inside of a debugging session in GDB.

You can also do make run, if you just want to run it, although you still need QEMU_PATH to be set up.

Contributions

Feel free to point out any mistakes or issues you've found while using this little thing!

Anything from a simple question to a pull request is really appreciated!