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Code: Select all

use16

mov ax, sp
mov [stackpointer], ax

keyloop:
	mov ah, 0
	int 0x16

	cmp al, 0x08
	je .bkspc

	cmp al, 0x0d
	je .ret

	call print_al
	call cursor_forward
	push ax
	jmp keyloop
.bkspc:
	call cursor_backward
	mov al, ' '
	call print_al
jmp keyloop
.ret:
	call cmdcmp
	call scroll_up
jmp keyloop

stackpointer dd 0
cmdstr db 'cls help',0
cmdsame db 1
cmdspcs db 0
cmdcmp:
	xor eax, eax
	mov ds, ax
	mov es, ax
	mov esi, [stackpointer]
	mov edi, cmdstr
	add esi, 1
	mov byte [cmdsame], 1
	mov byte [cmdspcs], 0
	cld
.loop:
	cmpsb
	add esi, 1
	je .loop
	
	cmp byte [edi], 32
	je .spc

	cmp byte [edi], 0
	je .end

	mov byte [cmdsame], 0
jmp .loop
.spc:
	cmp byte [cmdsame], 1
	je .match
	mov byte [cmdsame], 1
	add byte [cmdspcs], 1
	mov esi, [stackpointer]
	add esi, 1
jmp .loop
.end:
	mov ax, [stackpointer]
	mov sp, ax
	cmp byte [cmdsame], 1
	je .match
ret
.match:
	mov ax, [stackpointer]
	mov sp, ax
	cmp byte [cmdspcs], 0
	je .cls
	cmp byte [cmdspcs], 1
	je .help
ret
.cls:
	mov ah, 0x0f
	int 0x10
	mov ah, 0x00
	int 0x10
	mov ah, 2
	mov bh, 0
	mov dh, 0
	mov dl, 0
	int 0x10
ret
.help:
	
ret
print_al:
	mov ah, 9 ;write char and attr at cursor
	mov bh, 0 ;page
	mov bl, 0x0f ;color
	mov cx, 1 ;write times
	int 0x10
ret
cursor_getpos:
	mov ah, 3
	int 0x10
ret
cursor_forward:
	call cursor_getpos
	mov ah, 2 ;set cursor pos
	cmp dl, 79
	je .colmax
	add dl, 1
	int 0x10
ret
.colmax:
	cmp dh, 24
	je .rowmax
	mov dl, 0
	add dh, 1
	int 0x10
ret
.rowmax:
	mov dl, 0
	int 0x10
	call scroll_down
ret
cursor_backward:
	call cursor_getpos
	mov ah, 2 ;set cursor pos
	cmp dl, 0
	je .colmin
	sub dl, 1
	int 0x10
ret
.colmin:
	cmp dh, 0
	je .rowmin
	mov dl, 79
	sub dh, 1
	int 0x10
ret
.rowmin:
	mov dl, 79
	int 0x10
	call scroll_up
ret
scroll_up:
	mov ah, 6
	mov al, 1
	mov bh, 0x0f
	mov cx, 0
	mov dx, 0x4f4f
	int 0x10
ret
scroll_down:
	mov ah, 7
	mov al, 1
	mov bh, 0x0f
	mov cx, 0
	mov dx, 0x4f4f
	int 0x10
ret

Code: Select all

    db 0,"pleh slc"
cmdstr: