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| author | kotorifan <kotorifan05@gmail.com> | 2026-02-03 22:50:32 +0100 |
|---|---|---|
| committer | kotorifan <kotorifan05@gmail.com> | 2026-02-04 09:01:10 +0100 |
| commit | 8a0ab6de92c0e2b4260d6a149c43c58d004d74d9 (patch) | |
| tree | b1bfdc5d119dd01e6c603ddcb40b922e672b6c24 /src/boot/boot.stage1.asm | |
| parent | 7ce57a428f4c85771582c7f486c3553cacf80c15 (diff) | |
| download | kotori-os-8a0ab6de92c0e2b4260d6a149c43c58d004d74d9.tar.gz | |
Added common.asm
Diffstat (limited to 'src/boot/boot.stage1.asm')
| -rw-r--r-- | src/boot/boot.stage1.asm | 58 |
1 files changed, 29 insertions, 29 deletions
diff --git a/src/boot/boot.stage1.asm b/src/boot/boot.stage1.asm index d8dc84a..bb55dee 100644 --- a/src/boot/boot.stage1.asm +++ b/src/boot/boot.stage1.asm @@ -1,16 +1,8 @@ ;; boot.stage1.asm [bits 16] - + [org 0x7c00] global _start - %include "boot.stage1.print.asm" - - %define READ_SECTORS_NUM 64 - %define BOOT_LOAD_ADDR 0x7c00 - %define STAGE2_ADDR 0x7e00 - %define SECTOR_SIZE 512 - -section .boot_sector _start: ;; Setup segment registers @@ -18,26 +10,31 @@ _start: mov ds, ax mov es, ax mov ss, ax - mov gs, ax - mov fs, ax + mov sp, STACK_ADDR ; Adjust stack + + cld + + mov [drive], dl ; Get boot drive number + + ;; Show boot message + mov si, boot_msg + call _print_string + ;; Load Stage 2 + mov ah, 0x42 ; Extended read + mov dl, [drive] ; Set drive number + xor ax, ax + mov ds, ax mov si, DAP - mov ah, 0x42 ; Extended read function - mov dl, 0x80 ; Drive Number (starts at 0x80, thus it is 1) - int 0x13 + int 0x13 ; Read disk jc _disk_read_err -_ignore_disk_read_err: - mov si, _jmp_msg - call _print_string jmp 0x0000:STAGE2_ADDR + _disk_read_err: - cmp word [DAP.num_sectors], READ_SECTORS_NUM - jle _ignore_disk_read_err - - mov si, _disk_read_err_msg - call _print_string + mov si, disk_read_err_msg + call _print_string .halt: hlt jmp .halt @@ -46,14 +43,17 @@ _disk_read_err: DAP: db 0x10 ; Size of packet db 0 ; Zero - .num_sectors: dw READ_SECTORS_NUM ; Number of sectors to be read - dd (BOOT_LOAD_ADDR + SECTOR_SIZE) ; Destination address + dw STAGE2_ADDR ; Destination address + dw 0x0000 ; Segment dq 1 ; Which sector to start at -_disk_read_err_msg: db "Disk error", 13, 10, 0 -_jmp_msg: db "Jumping to Stage 2", 13, 10, 0 +drive: db 0 +disk_read_err_msg: db "Disk error", 13, 10, 0 +boot_msg: db "Booting", 13, 10, 0 + + %include "boot.stage1.print.asm" + %include "common.asm" - ;; Padding and magic number - times 510 - ($ - $$) db 0 - dw 0xaa55 + times 510-($-$$) db 0 + dw 0xAA55 |