Bug report source code

no_comments.asm

[org 0x7C00]
[bits 16]

%macro tty 1
	mov si, %1
	call Print
%endmacro

;; Clear the segment registers
xor ax, ax
mov ds, ax
mov ss, ax
mov bp, ss
mov sp, bp
mov gs, ax
mov fs, ax
mov es, ax

;; Far jump
jmp 0:Start

Start:
    call VideoMode
    tty MESSAGE
    jmp $


nop

VideoMode:
	mov ah, 0x0
	mov al, 0x2
	int 0x10

	ret

nop

Print:
	jmp .char

	.endl:
	
	mov ah, 0x3
	mov bh, 0x0	
	int 0x10

	;; dh = row (y)
	;; dl = column (x)
	xor dl, dl
	inc dh

	mov ah, 0x2
	mov bh, 0x0
	int 0x10

	.char:

	lodsb				;; Load the [al] register with the next
					;; byte/character from the string

	cmp al, 0x0
	je .end

	cmp al, 0x10
	je .endl

	mov ah, 0xE
	mov bh, 0x0
	int 0x10

	jmp .char

	.end:
	ret

MESSAGE: db "Hello, World!", 0x10, 0x0

;; Boot signature
times 510 - ($ - $$) db 0
dw 0xAA55

with_comments.asm

[org 0x7C00]
[bits 16]

%macro tty 1
	mov si, %1
	call Print
%endmacro

;; Clear the segment registers
xor ax, ax
mov ds, ax
mov ss, ax
mov bp, ss
mov sp, bp
mov gs, ax
mov fs, ax
mov es, ax

;; Far jump
jmp 0:Start

Start:
    call VideoMode
    tty MESSAGE
    jmp $

nop

VideoMode:
	mov ah, 0x0		;; \
	mov al, 0x2 		;; | Change the video mode to 80x25 text
	int 0x10		;; /

	ret

nop

Print:
	jmp .char

	.endl:
	
	mov ah, 0x3		;; \
	mov bh, 0x0		;; | Get the cursor position
	int 0x10		;; /

	;; dh = row (y)
	;; dl = column (x)
	xor dl, dl
	inc dh

	mov ah, 0x2		;; \
	mov bh, 0x0		;; | Set the new cursor position
	int 0x10		;; /

	.char:

	lodsb			;; Load the [al] register with the next
				;; byte/character from the string

	cmp al, 0x0		;; \ Check if the current character is
	je .end			;; / a null terminator

	cmp al, 0x10		;; \ Check for a newline character
	je .endl		;; /

	mov ah, 0xE		;; \
	mov bh, 0x0		;; | Teletype output
	int 0x10		;; / 

	jmp .char

	.end:
	ret

MESSAGE: db "Hello, World!", 0x10, 0x0

;; Boot signature
times 510 - ($ - $$) db 0
dw 0xAA55