The MIT License (MIT)
Copyright (c) 2014 Alex Smith aosmith@gmail.com
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
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This is a toy operating system. Right now it sets up the gdt and switches from real to protected mode.
You can build and run this project with make start.
I've been running this using bochs, so it includes a bochsrc.txt.
Right now this boots to protected mode and runs main from kernel.c. This just prints an X at the top left corner.
Build:
make all
Run:
make run
Clean:
make clean
Reset:
make reset
Dump an object file:
objdump -d basic.o
Dissassemble Binary:
nadisasm -b 32 basic.bin > basic.dis
Right now this should work on most linux systems (assuming you have nasm, gcc, ld, bochs, etc.).
This is simply the best way to learn about a computer on a very low level. Getting to the point of booting and running c code is short but complex, this is a springboard / reference.
Based on "Writing a Simple Operating System -- from Scratch" by Nick Blundell.