avr/dsk_cpm.asm

   1 ;    Various functions for the Interaction with the CPM Filesystem
   2 ;
   3 ;    Copyright (C) 2010 Frank Zoll
   4 ;
   5 ;    This file is part of avrcpm.
   6 ;
   7 ;    avrcpm is free software: you can redistribute it and/or modify it
   8 ;    under the terms of the GNU General Public License as published by
   9 ;    the Free Software Foundation, either version 3 of the License, or
  10 ;    (at your option) any later version.
  11 ;
  12 ;    avrcpm is distributed in the hope that it will be useful,
  13 ;    but WITHOUT ANY WARRANTY; without even the implied warranty of
  14 ;    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  15 ;    GNU General Public License for more details.
  16 ;
  17 ;    You should have received a copy of the GNU General Public License
  18 ;    along with avrcpm.  If not, see <http://www.gnu.org/licenses/>.
  19 ;
  20 ;    $Id$
  21 ;
  22
  23 #if CPMDSK_SUPPORT
  24
  25
  26         .cseg
  27
  28 cpm_lba_to_phys:
  29         ldd     temp ,z+PTAB_START+0    ; get startsector of partition
  30         ldd     temp2,z+PTAB_START+1
  31         ldd     yl,z+PTAB_START+2
  32         ldd     yh,z+PTAB_START+3
  33
  34         add     xl,temp                 ; add offset to startsector
  35         adc     xh,temp2
  36         adc     yl,_0
  37         adc     yh,_0
  38
  39         ret
  40
  41 ; ====================================================================
  42 ; Function: Add's a CP/M Partition to the Partition table
  43 ; ====================================================================
  44 ; Parameters
  45 ; --------------------------------------------------------------------
  46 ; Registers  : none
  47 ; Variables  : [r] seekdsk              Number of Disk to Read
  48 ;              [r] seeksec              Sector to read
  49 ;              [r] seektrk              Track  to read
  50 ; --------------------------------------------------------------------
  51 ; Description:
  52 ; ====================================================================
  53 cpm_add_partition:
  54
  55         ldi     temp,dskType_CPM
  56         std     y+0,temp
  57
  58         ldd     temp,z+PART_START
  59         std     y+1,temp
  60         ldd     temp,z+PART_START+1
  61         std     y+2,temp
  62         ldd     temp,z+PART_START+2
  63         std     y+3,temp
  64         ldd     temp,z+PART_START+3
  65         std     y+4,temp
  66
  67         ldd     temp,z+PART_SIZE+2
  68         ldd     temp2,z+PART_SIZE+3
  69         or      temp,temp2              ;part size larger than 65535 sectors?
  70         brne    cpm_add_prune
  71
  72         ldd     temp,z+PART_SIZE
  73         std     y+5,temp
  74         ldd     temp,z+PART_SIZE+1
  75         std     y+6,temp
  76         rjmp    cpm_add_e
  77
  78 cpm_add_prune:
  79         std     y+5,_255
  80         std     y+6,_255
  81
  82 cpm_add_e:
  83         ret
  84
  85 #endif /* CPMDSK_SUPPORT */
  86
  87 ; vim:set ts=8 noet nowrap
  88