cpm/IPL.MAC

   1 ;    CP/M IPL for avrcpm
   2 ;
   3 ;    Copyright (C) 2010 Sprite_tm
   4 ;
   5 ;    This program is free software: you can redistribute it and/or modify
   6 ;    it under the terms of the GNU General Public License as published by
   7 ;    the Free Software Foundation, either version 3 of the License, or
   8 ;    (at your option) any later version.
   9 ;
  10 ;    This program is distributed in the hope that it will be useful,
  11 ;    but WITHOUT ANY WARRANTY; without even the implied warranty of
  12 ;    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13 ;    GNU General Public License for more details.
  14 ;
  15 ;    You should have received a copy of the GNU General Public License
  16 ;    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  17 ;
  18 ;    $Id$
  19 ;
  20
  21 ; IPL for the CP/M-emu in an AVR. Loads CPM (CCP+BDOS+BIOS) from the 'disk'.
  22 ; Loads nsects (51) locical CPM sectors, starting from track 0 sector 2.
  23
  24         maclib  CFGACPM.LIB
  25
  26 nsects  equ     26*2 - 1        ;cold start sector count
  27
  28         .z80
  29         aseg
  30         org     100h
  31         .phase  2000h
  32
  33         ld      sp,2000h
  34         ld      hl,msgipl
  35         call    prmsg
  36
  37         ld      hl,ccp
  38         ld      de,128
  39         ld      c,1             ;sector 1
  40         ld      b,nsects
  41         xor     a
  42         out     (16),a          ;track 0
  43         out     (17),a          ;
  44 loadloop:
  45         ld      a,c             ;sector (base-0)
  46         out     (18),a
  47         ld      a,l             ;dma L
  48         out     (20),a
  49         ld      a,h             ;dma H
  50         out     (21),a
  51         ld      a,1 shl READ_FUNC
  52         out     (22),a
  53
  54         add     hl,de
  55         inc     c
  56         dec     b
  57         jp      nz,loadloop
  58
  59         jp      bios
  60
  61 prmsg:
  62         ld      a,(hl)
  63         or      a
  64         ret     z
  65         out     (2),a
  66         inc     hl
  67         jp      prmsg
  68
  69 msgipl: db      cr,lf
  70         db      "ipl"
  71         db      0
  72
  73         end
  74