Add some bios routines

bootloader/Makefile

@@ -2,7 +2,7 @@
 
 
 bootloader.bin: bootloader.asm
-	nasm -f bin -o $@ $^
+	nasm -f bin -o $@ $<
 
 clean:
 	rm bootloader.bin

bootloader/bootloader.asm

@@ -4,14 +4,23 @@
 ;Save the first adress with a label to complete the MBR at the end.
 start:
 
+
 ;Init CPU registers
 mov ax, 0x0C70	;Put bootloader adress in ax register
 mov ds, ax	;Init data segment
+mov ax, 0x8000
+mov ss, ax
+mov ax, 0xf000
+mov sp, ax
+
+call clearScreenIntBios
 
 ;Pause here !
 infiniteLoop:
 	jmp infiniteLoop
 
+%include "clearScreenIntBios.asm"
+
 ;Complete the MBR with nothing
 times 510 - ($ - start) db 0x0
 

bootloader/clearScreenIntBios.asm

@@ -0,0 +1,30 @@
+clearScreenIntBios:
+
+	;Save registers
+	push ax
+	push bx
+	push cx
+	push dx
+
+	mov ax, 0x0600 ;Clear
+	mov bx, 0x0F00 ;Color black behind white foreground
+
+	mov cx, 0x0000 ;Top left corner
+	mov dx, 0x5050 ;Bottom right corner 80x80
+
+	int 0x10 ;Clear the screen
+
+	;Restore registers
+	pop dx
+	pop cx
+	pop bx
+	pop ax
+
+	;Reset Cursor Position
+	call resetCursorPosIntBios
+
+	;Back to previous task
+	ret
+
+;Include resetCursorPosIntBios
+%include "resetCursorPosIntBios.asm"

bootloader/resetCursorPosIntBios.asm

@@ -0,0 +1,21 @@
+resetCursorPosIntBios:
+
+	;Save registers
+	push ax
+	push bx
+	push dx
+
+	mov ax, 0x0200  ;Move cursor interrupt
+	mov bx, 0x0000	; X position
+	mov dx, 0x0000	; Y Position
+
+	;Call 0x10 interrupt service
+	int 0x10
+
+	;Restore registers
+	pop dx
+	pop bx
+	pop ax
+
+	;Back to previous task
+	ret