[BITS 16]

  global _print_char
  global _get_char
  global _check_key
  global _set_cursor
   global _get_cursor_pos
    global _set_cursor_pos
  segment _TEXT class=CODE

  _print_char:
      push bp
      mov  bp, sp
      mov  ah, 0x0E       ; BIOS TTY write
      mov  al, [bp+4]     ; first arg: char c
      xor  bh, bh         ; page 0
      int  0x10
      pop  bp
      ret
_get_char:
          ; Returns: AL = ASCII char, AH = scancode
          ; Blocks until a key is pressed
          xor ah, ah                  ; Function 0: wait for keypress
          int 0x16
          xor ah, ah
          ret

_check_key:
          ; Non-blocking: returns ZF=1 if no key waiting
          mov ah, 0x01                ; Function 1: check buffer
          int 0x16
          jz .empty
          mov ax, 1
          ret                         ; ZF=0 means key available, AL/AH = key
    .empty:
    xor ax, ax
    ret
_set_cursor:
    mov ah, 0x01
    mov cx, 0x0607
    ret
_get_cursor_pos:
          mov  ah, 0x03
          xor  bh, bh
          int  0x10           ; DH = row, DL = col
          mov  ax, dx         ; DH->AH, DL->AL in one shot
          ret

_set_cursor_pos:
                push bp
                mov  bp, sp
                mov  ah, 0x02       ; AH=02h: set cursor position
                xor  bh, bh         ; page 0
                mov  dh, [bp+4]     ; row
                mov  dl, [bp+6]     ; col
                int  0x10
                pop  bp
                ret