Alopos.C

A hobby operating system / OS kernel for x86 (32-bit) written in C and some assembly (GAS). Relies on a Multiboot 1 (0.6.96) compliant bootloader (GRUB, etc.).

Implements

• Multiboot 1 (0.6.96) bootloader compliance
• as-small-as-possible assembly code for jumping into C and managing interrupts
• GDT
• interrupts (IDT)
• reads the memory map and other info from the Multiboot bootloader
• VGA text mode output / display
• keyboard input with UK keyboard layout

User-facing features

• Command line – case insensitive. Available commands:
  • help – prints an unhelpful message.
  • BootInfo – writes out info and memory map from the bootloader
  • CharsetTest – writes out all 256 characters in the VGA text mode character set
  • ColourTest – writes out all the combinations of background and foreground text colours.
  • GDTInfo – writes out info about the Global Descriptor Table (GDT)
  • VarSizes – writes out the sizes of the used C variable types.

Build dependencies

• MinGW
• i686-elf GCC
• QEMU

How to build

Copy /_local_templates/vars.cmd to /vars.cmd and edit the dependency directories to match where you've installed them.

Run build-run.bat to build and run in QEMU
Run build.bat to just build Run run.bat to just run in QEMU