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| author | kotorifan <kotorifan05@gmail.com> | 2026-01-31 13:32:57 +0100 |
|---|---|---|
| committer | kotorifan <kotorifan05@gmail.com> | 2026-02-04 09:01:10 +0100 |
| commit | dfe4a33865ef01c5068804f77da844cdebd87f00 (patch) | |
| tree | 46dd2fe032a0dc0358737147cbfe5cfd1ab60a56 /src/boot.stage1.asm | |
| parent | e0030889e85b070576c40917c649df3338a384df (diff) | |
| download | kotori-os-dfe4a33865ef01c5068804f77da844cdebd87f00.tar.gz | |
Added stage 1 of the bootloader + make.sh
Diffstat (limited to 'src/boot.stage1.asm')
| -rw-r--r-- | src/boot.stage1.asm | 56 |
1 files changed, 56 insertions, 0 deletions
diff --git a/src/boot.stage1.asm b/src/boot.stage1.asm new file mode 100644 index 0000000..c5bab26 --- /dev/null +++ b/src/boot.stage1.asm @@ -0,0 +1,56 @@ + ;; boot.stage1.asm + + %include "boot.common.asm" + %include "boot.stage1.print.asm" + [org 0x7c00] + [bits 16] + + %define READ_SECTORS_NUM 64 + %define BOOT_LOAD_ADDR 0x7c00 + %define SECTOR_SIZE 512 + + entry _start + +_start: + ;; Disable interrupts + cli + + ;; Setup segment registers + xor ax, ax + mov ds, ax + mov es, ax + mov ss, ax + + ;; Adjust Stack + mov sp, _start + + mov si, [disk_addr_packet] + mov ah, 0x42 ; BIOS extended read function + mov dl, 0x80 ; Drive number + int 0x13 ; BIOS disk services + jc _disk_read_err + + jmp 0x0000:0x7e00 + +_disk_read_err: + hlt + jmp _disk_read_err + +_end: + hlt + jmp _end + +disk_read_err_msg: db "Failed to read disk", 13, 10, 0 +disk_read_success_msg: db "Read the disk successfully", 13, 10, 0 +disk_addr_packet: + db 0x10 + db 0x0 +DAP_sectors_num: + dw READ_SECTORS_NUM ; Number of read sectors + dd (BOOT_LOAD_ADDR + SECTOR_SIZE) ; Destination address + dq 1 ; First sector after the boot sector + + ;; Padding and magic number + times 510 - ($ - $$) db 0 + dw 0xaa55 + |