Added file loading

src/boot.asm

@@ -7,16 +7,29 @@ start:
     xor ax, ax
     mov es, ax
     mov ds, ax
-    mov bp, 0x9000
+    mov bp, 0x7c00
     mov sp, bp
 
+    ; Save drive number
+    mov byte [driveNumber], dl
+
+    ; Print boot message
+    mov si, bootMsg
+    call print
+    mov dl, byte [driveNumber]
+    call printHex
+    mov si, newline
+    call print
+
     ; Read filetable from disk
     mov bx, FILETAB_LOC ; Filetable location in memory
     mov es, bx
     xor bx, bx
 
     mov ah, 2           ; Read from disk
-    mov al, 1           ; Read 1 sector
+    mov al, 1           ; Read 1 sector (512B)
+
+    mov dl, byte [driveNumber] ; Drive number
     mov ch, 0           ; Cylinder
     mov dh, 0           ; Head
     mov cl, 2           ; Sector
@@ -30,7 +43,9 @@ start:
     xor bx, bx
 
     mov ah, 2           ; Read from disk
-    mov al, 2           ; Read 2 sectors
+    mov al, 2           ; Read 2 sectors (1024B)
+
+    mov dl, byte [driveNumber] ; Drive number
     mov ch, 0           ; Cylinder
     mov dh, 0           ; Head
     mov cl, 3           ; Sector
@@ -46,13 +61,24 @@ start:
     mov gs, ax
     mov ss, ax
 
+    mov bl, byte [driveNumber]
+
     ; Far jump to the kernel
-    jmp KERNEL_LOC:0x0
+    jmp KERNEL_LOC:0x0000
 
 readFail:
+    mov si, diskErrorMsg
+    call print
     cli
     hlt
 
+%include "./src/print.asm"
+
+driveNumber: db 0
+
+bootMsg: db ENDL, "Booting kern.", ENDL, "Booting from drive ", 0
+diskErrorMsg: db "Disk Error!", ENDL, 0
+
 FILETAB_LOC equ 0x1000
 KERNEL_LOC equ 0x2000