First code; I don't know if it works

LICENSE

@@ -1,6 +1,6 @@
 MIT License
 
-Copyright (c) <year> <copyright holders>
+Copyright (c) 2023 Eric-Paul Ickhorn
 
 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:
 

build.sh

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+#!/bin/env bash
+
+cd stage_1
+./build.sh
+cd ../
+
+cd stage_2
+./build.sh
+cd ../
+
+

run.sh

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+#!/bin/env bash
+
+

stage_1/build.sh

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+#!/bin/env bash
+
+nasm -fbin start.asm -o stage_1.bin

stage_1/start.asm

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+
+section .text
+org 0x7c00
+start:
+    
+    push dx
+    
+    mov ax, 0
+    mov ds, ax
+    mov es, ax
+    mov gs, ax
+    mov fs, ax
+    
+    mov ax, 0x7e00
+    mov ss, ax
+    
+    mov sp, 256
+    mov bp, 256
+    
+    mov ax, 0x7c00
+    add ax, 446
+    ; ax now points to the start of the partition table
+    
+    mov di, 0
+    
+    
+    
+.search_partition:
+    
+    mov bx, ax
+    add bx, 4
+    mov cl, [bx]
+    cmp cl, 0x9d
+    je .found_partition
+    
+    inc di
+    cmp di, 4
+    je .no_boot_partition
+    add ax, 16
+    
+    
+    
+.found_partition:
+    
+    mov bx, ax
+    add bx, 14
+    mov cx, [bx]        ; more than 65536 sectors will NOT be
+                        ; supported for the bootloader's partition!
+    
+    mov bx, 0x8000
+    mov es, bx
+    mov di, 0x0000
+    
+    mov bx, ax
+    inc bx
+    ; bx now points to the CHS-address of the first sector
+    ; of the bootloader's partition.
+    
+    mov dx, [bx]
+    mov ah, dh          ; head
+    mov bl, dl          ; sector
+    
+    add bx, 2
+    ; bx now points to the CHS-cylinder of the first sector
+    ; of the bootloader's partition.
+    
+    mov al, [bx]        ; cylinder
+    
+    call load_sectors
+    
+    
+    
+.no_boot_partition:
+    
+    hlt
+
+%include "gdt.asm"
+%include "utility.asm"

stage_1/utility.asm

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+
+section .text
+
+; ax: start_sector (lower)
+; bl: start_sector (upper)
+; cx: sector_count
+; dh: drive
+; es: buffer_address (upper)
+; di: buffer_address (lower)
+load_sectors:
+    
+.prolog:
+    push ax
+    push bx
+    push cx
+    push dx
+    
+    xor si, si          ; current sector index
+    
+; sets the arguments for the first run of '.load_data'
+; which loads until the first CHS - cylinder boundary
+.set_first_load_args:
+    
+    ; the first read only reads up to the next cylinder boundary,
+    ; but potentially less (if not that many sectors have been requested)
+    
+    ; TODO================================================================================
+    mov bx, sp
+    add bx, 4
+    mov cx, [bx]        ; get sector count
+    sub cx, si          ; cx = num_missing_sectors
+    
+    
+    mov bx, sp
+    mov bx, [bx]
+    cmp cx, bx
+    js .load_data       ; if there are more sectors needed after the
+                        ; next cylinder boundary
+    ; if not that many sectors are needed, just read as
+    ; many sectors as are needed in total
+    mov cx, bx
+    
+    jmp .load_data
+    
+    
+    
+; sets the arguments for a run of '.load_data' after the
+; first one; aligned on a CHS - cylinder boundary
+.set_load_args:
+    
+    mov bx, sp
+    add bx, 4
+    mov cx, [bx]
+    sub cx, si          ; cx = num_missing_sectors
+    
+    cmp cx, 64
+    js .load_data
+    ; if this goes here, there are more than 64 sectors missing
+    ; -> clamp them to 64 so they can be loaded.
+    mov cl, 64
+    jmp .load_data      ; redundant
+    
+; loads at most 64 sectors from the disk into the main memory
+; ax: scratchpad
+; bx: start_sector (low part)
+; ch: start_sector (high part)
+; cl: num_sectors
+.load_data:
+    
+    mov bx, sp
+    
+    mov ah, 0x02
+    mov al, cl
+    mov dl, [bx]        ; drive
+    mov dh, bh          ; head
+    mov cl, ch          ; sector
+    mov ch, bl          ; cylinder
+    mov bx, di          ; buffer address (lower)
+    int 0x13
+    
+.continue_if_needed:
+    
+    ; check if there still are sectors missing to load
+    mov bx, sp
+    add bx, 4
+    mov cx, [bx]        ; sector_count
+    
+    cmp si, cx
+    js .set_load_args
+    
+    
+    
+.epilog:
+    
+    pop dx
+    pop cx
+    pop bx
+    pop ax
+    
+    ret

stage_2/build.sh

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+#!/bin/env bash
+
+