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BITS 16

start:
	mov ax, 07C0h		; Set up 4K stack space after this bootloader
	add ax, 288		; (4096 + 512) / 16 bytes per paragraph
	mov ss, ax
	mov sp, 4096

	mov ax, 07C0h		; Set data segment to where we're loaded
	mov ds, ax


	mov si, text_string	; Put string position into SI
	call print_string	; Call our string-printing routine

	jmp find

	jmp $			; Jump here - infinite loop!


	text_string db 'Ram contents from 0x7c0:0x0000 are : ', 0
	ram_byte db 65

print_string:			; Routine: output string in SI to screen
	mov ah, 0Eh		; int 10h 'print char' function

.repeat:
	lodsb			; Get character from string
	cmp al, 0
	je .done		; If char is zero, end of string
	int 10h			; Otherwise, print it
	jmp .repeat

.done:
	ret

find:
	mov cx,65535
	mov edx,0
again:
	mov al,[edx]
	cmp al,0
	jne print
	inc edx
	dec cx
	cmp cx,0
	jne again
	hlt

print:
	mov ah,0eh
	mov cx,512
print_again:	mov al,[edx]
	int 10h
	inc edx
	dec cx
	cmp cx,0
	jne print_again
	sub edx,512         ;Make edx equal to the loaction where it first found the non-zero byte
	ror edx,24         ; 
	mov al,dl          ;
	int 10h            ;
	rol edx,8          ;
	mov al,dl          ;
	int 10h            ;
	rol edx,8          ; Output the contentes of edx 
	mov al,dl          ;
	int 10h            ;
	rol edx,8          ;
	mov al,dl          ;
	int 10h            ;
	jmp $              ; Jump here
	
	
	times 510-($-$$) db 0	; Pad remainder of boot sector with 0s
	dw 0xAA55		; The standard PC boot signature 

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mov edx,0
again: mov al,[edx] 

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mov al,[edx]

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mov al, [edx]

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mov al, [ds:edx]

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mov ax, 0x00
mov es, ax
mov al, [es:edx]