; Memory layout:
%define self      0x00600 ; 1 sector
%define prog      0x07C00 ; 1 sector

org self
cpu 8086

init:
  cli

  ; Stack grows down from PSP + 64k
  xor ax, ax
  mov ss, ax
  mov sp, ax

  push dx

  ; Relocate from [prog] to [self]
  mov ds, ax
  mov es, ax
  mov si, prog
  mov di, self
  mov cx, 0x100
  rep movsw

  jmp 0:main

main:
  mov bp, 0x0035
  mov WORD [dap.blocknum], 1
  mov si, dap
  mov ah, 0x42
  stc
  int 0x13
  jc error
  mov cx, [dap.blocknum]
  int3

error:
  mov ax, bp
  mov ah, 0x0e
  mov bx, 7
  int 0x10
  mov al, 0x21
  int 0x10
  xor ax, ax
  int 0x16
  int 0x19

dap:
.size:
  db 0
  db 0
.count:
  dw 1
.buffer:
  dw prog
  dw 0
.blocknum:
  dq 0

times (0x1BE - ($-$$)) db 0
part1:
  db 0x80
.chs_start:
  db 0xFF, 0xFF, 0xFF
.type:
  db 0x01
.chs_end:
  db 0xFF, 0xFF, 0xFF
.begin:
  dd 1
.end:
  dd (FLOPPY * 2)

times (0x1FE - ($-$$)) db 0
dw 0xAA55