cpu 8086

self:    equ 0xF000
diskbuf: equ (self-0x200) ; deblocking
stack:   equ (diskbuf) ; grows down
defdrv:  equ 4

org self
jmp init
pad 3

self_offset:
  db (self >> 8)

banner:
  db "RDOS 2019-09", 0x0A, 0x0D, '$', 0

init:
  mov sp, stack
  mov byte [defdrv], 0x01

  mov dx, banner
  call print_string

  call disk_parm_init

  mov dl, 0x00
  call disk_select

  cli
.halt:
  hlt
  jmp .halt

init_program:
  db "HELLO.COM", 0

cpm_syscall:
  cmp cl, 0
  je init
  cmp cl, 1
  je console_input
  cmp cl, 2
  je console_output
  cmp cl, 9
  je print_string
  cmp cl, 10
  je read_buffer
  stc
  ret

%include "char.asm"

%include "exec.asm"
%include "fdc.asm"
%include "fcb.asm"
%include "fcbparse.asm"
%include "disk.asm"
%include "log2.asm"
%include "dump.asm"