X-Git-Url: http://git.dujemihanovic.xyz/posts?a=blobdiff_plain;f=boot.s;h=3a8adc70a9d275e2e17faa53e6772aee0289e36c;hb=d826097f3b032247dd0396f8cf64b2fa775cea68;hp=51be5d92dd8ee19426be4092d2aaed2c1e96f46d;hpb=eec791adfbaddde2f5724e0f5c7319e7d2aaef0e;p=nameless-os.git

diff --git a/boot.s b/boot.s
index 51be5d9..3a8adc7 100644
--- a/boot.s
+++ b/boot.s
@@ -2,70 +2,32 @@
 	org 7c00h ; boot sector is loaded at 0x7c00
 
 _start
-	mov di, printing_numbers
-	call print
+	mov [boot_drive], dl ; BIOS sets dl to number of boot drive, we don't want to forget this
 
-	or bl, 1
-	mov dx, 0DEADh ; number to print
-	call print_word
-	
-	mov di, space
-	call print
-	
-	xor bl, bl
-	mov dx, 0BEEFh
-	call print_word
-
-	mov di, waiting
-	call print
+	mov bp, 8000h ; Move the stack away
+	mov sp, bp
 
-	mov di, keystroke
-	mov bl, 1
+	push cs
+	pop es
+	mov bx, 9000h ; Load at 0000:9000
+	mov dh, 2 ; Load 5 sectors
+	mov dl, [boot_drive] ; Load from boot drive
+	call read_sectors
 
-.loop
-	mov ah, 0
-	int 16h
-	cmp ah, 1Ch
-	je .enterpressed
-	jmp .continue
-	cmp ah, 0Eh
-	je .backspace
-	jmp .continue
-.enterpressed
-	pusha
-	mov ah, 0Eh
-	mov al, 0Dh
-	int 10h
-	mov al, 0Ah
-	int 10h
-	popa
-	jmp .loop
-.backspace
-	pusha
-	mov ah, 03h
-	mov bh, 0
-	int 10h
-	dec dl
-	mov ah, 02h
-	int 10h
-	mov ah, 0Eh
-	mov al, ' '
-	int 10h
-	mov ah, 02h
-	int 10h
-	popa
-	jmp .loop
-.continue
-	mov [keystroke], al
-	call print
-	jmp .loop
+	mov dx, [9000h] ; Print value at 9000h, should be 0xDEAD
+	call print_word 
+	mov dx, [9000h + 512] ; Print value at 9200h, should be 0xBEEF
+	call print_word
 
-printing_numbers db "Printing some random hex numbers", 0
-waiting db "I await keystrokes", 0
-keystroke db "$", 0
-space db " ", 0
+	jmp $ ; Endless loop
 
 %include "print.s"
+%include "disk.s"
+
+boot_drive resb 1 ; Reserve 1 byte for boot drive number
+
+times 510-($-$$) db 0 ; fill with 0 until 0x1fc is reached
+dw 0AA55h ; BIOS MBR signature
 
-	times 510-($-$$) db 0 ; fill with 0 until 0x1fc is reached
-	dw 0AA55h ; BIOS MBR signature
+times 256 dw 0DEADh ; Fill in 2nd sector with 0xDEAD
+times 256 dw 0BEEFh ; Fill in 3rd sector with 0xBEEF