console_hide_cursor:
  push ax
  push cx
  mov ah, 1
  mov cx, 0x1F1F
  int 0x10
  pop cx
  pop ax
  ret

console_show_cursor:
  push ax
  push cx
  mov ah, 1
  mov cx, 0x001F
  int 0x10
  pop cx
  pop ax
  ret

; Raw console i/o without echo
; IN   DL  character to output or FF
; OUT  ZF  if DL=FF: zero if character input
;      AL  if not ZF: ascii char, otherwise corrupt
console_io:
  cmp dl, 0xFF
  je .read
  push ax
  push bx
  mov al, dl
  mov ah, 0x0e
  xor bx, bx
  int 0x10
  pop bx
  pop ax
  ret
.read:
  call console_show_cursor

  ; if no character avail, exit with leaving
  ; cursor displayed
  mov ah, 1
  int 0x16
  jz .end
  pushf

  ; actually read character
  xor ax, ax
  int 0x16

  call console_hide_cursor

  ; restore zero flag
  popf
.end:
  ret