[org 0x0100]

jmp main_funtion

ID: db 10, 13,'$'

Length_of_buffer: db 80 ; length of buffer

db 0 ; number of characters on return

times 80 db 0 ; actual buffer space

string_length: dw 11 ; length of the string

; subroutine to clear the screen

clearscreen:

  push es

  push ax

  push di

  mov ax, 0xb800

  mov es, ax 

  xor di, di 

  mov cx, 80*20 

clr_loop:

  mov word [es:di], 0x0700 

  add di, 2 

  loop clr_loop 

  pop di

  pop ax

  pop es

  ret

output_string:

  push bp

  mov bp, sp

  push es

  push ax

  push cx

  push si

  push di

  mov ax, 0xb800

  mov es, ax 

  xor di, di 

  mov si, [bp+6] 

  mov cx, [bp+4] 

mov ah, 0xFF 

print_loop:

  mov al, [si] 

  mov ah, [si+1] 

  mov [es:di], ax

  add di, 2 

  add si, 1 

  loop print_loop 

  pop di

  pop si

  pop cx

  pop ax

  pop es

  pop bp

  ret 4

main_funtion:

  mov dx, Length_of_buffer

  mov ah, 0x0A 

  int 0x21

  mov bh, 0

  mov bl, [Length_of_buffer+1]

  mov byte [Length_of_buffer+2+bx], '$' 

  mov ax, Length_of_buffer+2 

  push ax 

  push word [string_length] 

  call clearscreen 

  call output_string 

  mov ax, 0x4c00 

  int 0x21