other projects

https://github.com/cs107e/cs107e.github.io
http://wiki.osdev.org/Calling_Conventions
http://wiki.osdev.org/Linker_Scripts
http://wiki.osdev.org/Printing_To_Screen
http://wiki.osdev.org/Exceptions#General_Protection_Fault
https://en.wikipedia.org/wiki/X86_calling_conventions
http://repo.or.cz/w/lightOS.git
https://littleosbook.github.io/
http://www.muppetlabs.com/~breadbox/software/tiny/teensy.html

http://x86.renejeschke.de/html/file_module_x86_id_139.html
http://retired.beyondlogic.org/serial/serial1.htm
https://pdos.csail.mit.edu/6.828/2014/reference.html

https://visopsys.org/osdev/
sortix, soso, managarm (mlibc)
https://bitbucket.org/adamholisky/versionone 
https://collapseos.org/
https://github.com/mikaku/Fiwix

tutorials:

https://littleosbook.github.io
http://www.henkessoft.de/OS_Dev/OS_Dev1.htm
http://www.brokenthorn.com/Resources/OSDevIndex.html
- fitting code following the brokenthorm tutorial:
  https://github.com/tuhdo/os-study
http://www.fysnet.net/
http://www.brokenthorn.com/Resources/

In C#:
https://github.com/FlingOS/FlingOS

In Rust:
http://os.phil-opp.com/

OS with striclty types language:
http://web.yl.is.s.u-tokyo.ac.jp/~tosh/talk/

Interrupts:
http://wiki.osdev.org/Exceptions
http://wiki.osdev.org/Interrupt_Descriptor_Table
http://beefchunk.com/documentation/hardware/microprocessors/intel/i80386/Chap9.html
http://www.cs.cmu.edu/~ralf/files.html
https://blog.packagecloud.io/eng/2016/04/05/the-definitive-guide-to-linux-system-calls/

A20:
http://wiki.osdev.org/A20_Line#Recommended_Method
http://aodfaq.wikidot.com/mc-a20-controls
http://www.independent-software.com/writing-your-own-toy-operating-system-enabling-the-a20-line/
https://www.win.tue.nl/~aeb/linux/kbd/A20.html

longjmp:
http://blog.reverberate.org/2013/05/deep-wizardry-stack-unwinding.html
http://prettyos.de

PIC:
http://www.brokenthorn.com/Resources/OSDevPic.html
http://wiki.osdev.org/8259_PIC

keyboard:
http://wiki.osdev.org/"8042"_PS/2_Controller
https://www.lowlevel.eu/wiki/Keyboard_Controller

PIT:
http://wiki.osdev.org/Programmable_Interval_Timer

PCI:
http://wiki.osdev.org/PCI
https://www.lowlevel.eu/wiki/Peripheral_Component_Interconnect
http://www.ics.uci.edu/~harris/ics216/pci/PCI_22.pdf
/usr/share/hwdata/pci.ids

assembly:
NASM
FASM

serial:
http://wiki.osdev.org/Serial_Ports
http://www.sci.muni.cz/docs/pc/serport.txt

Boot:
https://www.cs.cmu.edu/~410-s07/p4/p4-boot.pdf
http://www.osdever.net/tutorials/view/loading-sectors
http://www.osdever.net/tutorials/view/lba-to-chs
LILO boot loader
http://www.uruk.org/orig-grub/PC_partitioning.txt
http://wiki.osdev.org/ATA_in_x86_RealMode_%28BIOS%29
other Boot (not used, but nice other projects):
https://github.com/vladimirfedorov/bootsector.git: stage1 with FAT, using FASM
https://github.com/civboot/civboot

C:
http://www.drdobbs.com/extending-c-for-object-oriented-programm/184402731
https://www.state-machine.com/doc/AN_OOP_in_C.pdf
https://www.cs.rit.edu/~ats/books/ooc.pdf
https://lwn.net/Articles/444910/
https://dmitryfrank.com/articles/oop_in_c

VGA:
http://www.inp.nsk.su./~bolkhov/files/fonts/univga/
https://sourceforge.net/projects/bdf2c/
http://files.osdev.org/mirrors/geezer/osd/graphics/modes.c
http://www.osdever.net/FreeVGA/home.htm
http://wiki.osdev.org/VGA_Fonts
http://bos.asmhackers.net/docs/vga_without_bios/
abaos: daveho https://int10h.org/oldschool-pc-fonts/fontlist/
https://os.phil-opp.com/vga-text-mode/

GUI:
https://github.com/vurtun/nuklear
http://webserver2.tecgraf.puc-rio.br/iup/

linker:
https://stackoverflow.com/questions/26143123/how-do-i-ensure-the-entry-function-at-a-fixed-address-of-bare-metal-arm

Linux:
https://blog.packagecloud.io/eng/2016/04/05/the-definitive-guide-to-linux-system-calls/

Security:
http://wiki.osdev.org/Stack_Smashing_Protector

Memory management:
http://www.codinglabs.net/tutorial_memory_pool.aspx
http://wiki.osdev.org/Detecting_Memory_(x86)

Networking:
http://wiki.osdev.org/RTL8139
http://lowlevel.eu/wiki/RTL8139
https://gist.github.com/pdumais/f5a2aff025fc7a3fe6bc
http://linuxgazette.net/156/jangir.html
http://blog.elastocloud.org/2015/07/qemukvm-bridged-network-with-tap.html

Ethernet:
https://en.wikipedia.org/wiki/Ethernet_frame
https://en.wikipedia.org/wiki/EtherType
http://www.hackersdelight.org/hdcodetxt/crc.c.txt

ARP:
https://tools.ietf.org/html/rfc826
http://wiki.osdev.org/Address_Resolution_Protocol

Syscalls:
AX, BX software interrupt 0x80, classic Linux/DOS/Windows syscalls

UTP/Netconsole:
https://www.cyberciti.biz/tips/linux-netconsole-log-management-tutorial.html

intro in gas and nasm
https://developer.ibm.com/articles/l-gas-nasm/

https://github.com/wbenny/ia32-doc

https://www.jwz.org/doc/worse-is-better.html

http://www.independent-software.com/operating-system-development-jumping-to-protected-mode.html

https://wiki.osdev.org/Bare_Bones
https://wiki.osdev.org/OS_Specific_Toolchain
https://wiki.osdev.org/GCC_Cross-Compiler
BOOTBOOT
https://forum.osdev.org/viewtopic.php?f=2&t=33362

https://github.com/jtsiomb/pcboot/
minimal 32-bit protected mode booting kernel

https://github.com/Supercip971/WingOS

boot loader
https://github.com/limine-bootloader/limine
q-word OS:
https://github.com/qword-os/echfs
https://github.com/qword-os/lvlibc
https://github.com/Supercip971/WingOS_x64.git

echfs, simple filesystem
https://github.com/echfs/echfs, 32-bit port needed

prex real time embedded os:
https://github.com/AndrewD/prex

https://github.com/spacerace/romfont

etherboot, gPXE, iPXE, HTTP boot:
https://sites.google.com/site/richardgroux/infrastructure-1/Network/pxe-boot/what-is-gpxe-1
linux floppy code has been removed in 2003, had a 1MB limit issue anyway