Boot sector complete

boot.asm

@@ -1,8 +1,45 @@
 [org 0x7c00]
+section BOOTSECTOR start=7C00h
 
+OS_SEGMENT equ 0x100
+
+; https://github.com/cfenollosa/os-tutorial
 boot:
-    mov bx, HELLO_WORLD2
-    call println
+    ; Load from disk
+    mov ah, 0x02 ; read
+    mov al, 0x01 ; No of sectors (1)
+    mov cl, 0x02 ; Sector start (1 = boot sector, 2 = OS)
+    mov ch, 0x00 ; Cylinder 0
+    mov dh, 0x00 ; Head 0
+    
+    mov bx, OS_SEGMENT ; Set target segment
+    mov es, bx
+    mov bx, 0x0 ; Target offset in segment
+    
+    int 0x13      ; Send read interrupt
+    jc disk_error
+    
+    ; Now that the OS is loaded in 0x1000, let's call main!
+    jmp 0x100:0x0
+
+disk_error:
+    mov si, DISK_ERR_MSG
+    call bs_print
+    jmp $
+    
+; https://stackoverflow.com/a/53403853
+bs_print:
+    mov     ah, 0x0e            ; BIOS TTY function
+    
+    .L0:
+        lodsb
+        or      al, al
+        jnz     .J0
+        ret
+    .J0:
+    
+    int     0x10
+    jmp     .L0
 
 jmp $ ; Halt
 
@@ -10,7 +47,8 @@ jmp $ ; Halt
 
 
 ; Boot sector data
-
+DISK_ERR_MSG:
+    db 'DISK ERROR: Failed to load kernel!', 0
 
 ; Boot sector padding and magic number
 times 510-($-$$) db 0

main.asm

@@ -1,6 +1,9 @@
 ; Bootloader
 %include "boot.asm"
 
+
+section KERNEL follows=BOOTSECTOR vstart=1000h
+
 main:
     mov bx, HELLO_WORLD
     call println