Save File Function - Amateur OS Dev (x86 asm)
20Creating new save_file & load_file functions for loading & saving sectors to & from the disk, using BIOS int 13h, AH02h/03h. 'save_file.inc' is added to the current editor and tested at the end with a small program to print a 'T' and halt.
Eventually I want to use ATA instructions with ports to read/write sectors to replace the use of these BIOS interrupts.
In today's excuse for my bad coding, this was recorded last week, around 6/28-7/4. I'm in a legal fireworks area and the neighbors greatly exercised this right late into the night. I was also on-call for work and did not have much sleep in these video segments. I'll try to have a better excuse for the next video!
PDF for 32bit C calling convention example: https://aaronbloomfield.github.io/pdr/book/x86-32bit-ccc-chapter.pdf
There is also a 64-bit example at that domain
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Playlist for this series:
https://www.youtube.com/playlist?list=PLT7NbkyNWaqajsw8Xh7SP9KJwjfpP8TNX
Git repos:
https://git.sr.ht/~queso_fuego/quesos
https://github.com/queso-fuego/amateuros
Software used:
VMware Workstation Player - https://www.vmware.com/products/workstation-player/workstation-player-evaluation.html
openBSD - https://www.openbsd.org/
qemu - https://www.qemu.org/
vim - https://www.vim.org/ (neovim is probably better :p)
fasm - https://flatassembler.net/
Suggest content you would like to see live, programming, gaming, or otherwise, through youtube comments or by email.
Stream archive channel- https://www.youtube.com/channel/UCxi12g3jdQMFiFTA5GVcGMA
Contact:
email - fuegoqueso@gmail.com
twitter - @Queso_Fuego
Updates for this series might be tweeted out as they happen, if I remember (not likely). YT channel community tab in the future if channel metrics are met. Though if people prefer, I can look into a mailing list for updates
Thoughts/Notes/Suggestions/Other - Drop a message in the video comments or by email
Credits:
Music from https://incompetech.com:
"Your Call" by Kevin MacLeod (https://incompetech.com)
Licence: CC BY (http://creativecommons.org/licenses/by/4.0/)
The blue title tags:
#osdev #programming #assembly