cpm/bios.mac

   1 ;    CP/M BIOS for avrcpm
   2 ;    Copyright (C) 2010 Sprite_tm
   3 ;
   4 ;    This program is free software: you can redistribute it and/or modify
   5 ;    it under the terms of the GNU General Public License as published by
   6 ;    the Free Software Foundation, either version 3 of the License, or
   7 ;    (at your option) any later version.
   8 ;
   9 ;    This program is distributed in the hope that it will be useful,
  10 ;    but WITHOUT ANY WARRANTY; without even the implied warranty of
  11 ;    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  12 ;    GNU General Public License for more details.
  13 ;
  14 ;    You should have received a copy of the GNU General Public License
  15 ;    along with this program.  If not, see <http://www.gnu.org/licenses/>.
  16 ;
  17 ;    $Id: bios.asm 71 2010-08-06 19:38:10Z leo $
  18 ;
  19
  20         maclib  CFGACPM.LIB
  21
  22         aseg
  23         org     100h
  24         .phase  bios
  25         .z80
  26
  27 nsects  equ     ($-ccp)/128     ;warm start sector count
  28
  29         jp boot
  30 wboote:
  31         jp wboot
  32         jp const
  33         jp conin
  34         jp conout
  35         jp list
  36         jp punch
  37         jp reader
  38         jp home
  39         jp seldsk
  40         jp settrk
  41         jp setsec
  42         jp setdma
  43         jp read
  44         jp write
  45         jp listst
  46         jp sectran
  47
  48         .8080
  49         maclib AVRCPM.LIB
  50
  51         ;Drive   A    B    C    D    E F G H I    J    K    L
  52 ;drvtbl: dtbl   <dpha,dphb,dphc,dphd, , , , ,dphi,dphj,dphk,dphl>
  53 ;drvtbl:        dtbl    <dpha,    ,    ,    , , , , ,dphi,dphj,dphk,dphl>
  54 drvtbl: dtbl    <    ,    ,    ,    , , , , ,dphi,dphj,dphk,dphl>
  55
  56         ;       Name   spt   bls  dks  dir  cks off
  57 ;       dpb     dpb243, 26, 1024, 243,  64,  64,  2
  58 ;       dpb     dp8192s,32, 4096,2046, 512, 512,  2
  59 ;       dpb     dp8192, 32, 4096,2046,1024,1024,  2
  60 ;       dpb     dpbrd,  32, 1024,  56,  32,   0,  2
  61         dpb     rd1016, 32, 2048, 508, 192,   0,  2
  62         dpb     rd1024, 32, 2048, 512, 192,   0,  0
  63         dpb     rd0960, 32, 2048, 480, 192,   0,  0
  64
  65 ;dpha:  dph     dpb243
  66 ;dphb:  dph     dpb243
  67 ;dphc:  dph     dpb243
  68 ;dphd:  dph     dpb243
  69 ;dpha:  dph     dp8192s
  70 ;dphb:  dph     dp8192s
  71 ;dphc:  dph     dp8192
  72 ;dphd:  dph     dp8192
  73 dphi:   dph     rd1016
  74 dphj:   dph     rd1024
  75 dphk:   dph     rd1024
  76 dphl:   dph     rd0960
  77
  78         .z80
  79
  80 signon:
  81         db      cr,lf
  82         db      msize/10+'0'
  83         db      msize - (msize/10)*10 + '0'     ;modulo doesn't work?
  84         db      "k cp/m vers 2.2"
  85 msgnl:  db      cr,lf,0
  86
  87 msgnodisk:
  88         db      "No disk!"
  89         db      cr,lf,0
  90
  91 const:
  92         in a,(0)
  93         ret
  94
  95 conin:
  96         in a,(0)
  97         cp 0ffh
  98         jp nz,conin
  99
 100         in a,(1)
 101         ret
 102
 103 conout:
 104         ld a,c
 105         out (1),a
 106         ret
 107
 108 list:
 109         ret
 110
 111 listst:
 112         ld a,0
 113         ret
 114
 115 punch:
 116         ret
 117
 118 reader:
 119         ld a,01Fh
 120         ret
 121
 122 prmsg:
 123         ld      a,(hl)
 124         or      a
 125         ret     z
 126         push    hl
 127         ld      c,a
 128         call    conout
 129         pop     hl
 130         inc     hl
 131         jp      prmsg
 132
 133 prhex:
 134         ld      a,c
 135         push    af
 136         rra
 137         rra
 138         rra
 139         rra
 140         call    prhexdigit
 141         pop     af
 142         ;       fall thru
 143
 144 prhexdigit:
 145         and     00fh
 146         cp      10
 147         jp      c,prd1
 148         add     a,7
 149 prd1:
 150         add     a,'0'
 151         ld      c,a
 152         jp      conout
 153
 154 boot:
 155         ld      sp,buff
 156         ld      hl,signon
 157         call    prmsg
 158
 159         ld      a,low bcb
 160         out     (13),a
 161         ld      a, high bcb
 162         out     (14),a
 163
 164         xor     a
 165         ld      (bootdsk),a
 166         ld      e,a
 167         ld      c,a
 168         call    seldsk
 169         jp      nz,boot0
 170         ld      hl,msgnodisk
 171         call    prmsg
 172         halt
 173 boot0:
 174         call    getdpb
 175         ld      a,(de)                  ;dpb[0] is sectors_per_track
 176         ld      (bootspt),a
 177         ld      e,0
 178         ld      c,'I'-'A'
 179         call    seldsk
 180         jp      z,boot1         ;no ram disk
 181
 182         call    getdpb          ;de = dpb of first ram disk
 183
 184 ; Check, if we have reserved tracks.
 185
 186         ld      hl,13
 187         add     hl,de
 188
 189         ld      a,(hl)          ;# of reserved tracks
 190         inc     hl
 191         or      (hl)
 192         jp      z,boot1         ;Skip if not.
 193
 194 ; Save CPM to ram disk.
 195
 196         ld      a,(de)          ;sectors per track
 197         ld      (bootspt),a
 198         ld      a,'I'-'A'
 199         ld      (bootdsk),a
 200         call    home
 201         ld      b,nsects
 202         ld      c,0             ;track
 203         ld      d,1             ;sektor (0 based, skip ipl)
 204         ld      hl,ccp
 205 store1:
 206         push    bc
 207         push    de
 208         push    hl
 209         ld      c,d
 210         ld      b,0
 211         call    setsec
 212         pop     bc              ;dma
 213         push    bc
 214         call    setdma
 215         ld      c,0
 216         call    write
 217
 218         pop     hl              ;dma
 219         ld      de,128
 220         add     hl,de
 221         pop     de              ;d = sec
 222         pop     bc              ;b = # of secs, c = track
 223         dec     b
 224         jp      z,boot1
 225
 226         inc     d
 227         ld      a,(bootspt)
 228         dec     a
 229         cp      d               ;if sector >= spt then change tracks
 230         jp      nc,store1
 231
 232         ld      d,0
 233         inc     c
 234         push    bc
 235         push    de
 236         push    hl
 237         ld      b,0
 238         call    settrk
 239         pop     hl
 240         pop     de
 241         pop     bc
 242         jp      store1
 243
 244 boot1:
 245         xor     a
 246         ld      (iobyte),a
 247         ld      (cdisk),a
 248         jp      gocpm
 249
 250 wboot:  ;re-load CP/M
 251         ld      sp,buff
 252         ld      a,1 shl BOOT_FUNC       ;init (de)blocking
 253         out     (22),a
 254         ld      a,(bootdsk)
 255         ld      c,a
 256         call    seldsk
 257         call    home
 258         ld      b,nsects
 259         ld      c,0             ;track
 260         ld      d,1             ;sektor (0 based)
 261         ld      hl,ccp
 262 load1:
 263         push    bc
 264         push    de
 265         push    hl
 266         ld      c,d
 267         ld      b,0
 268         call    setsec
 269         pop     bc
 270         push    bc
 271         call    setdma
 272         call    read
 273         cp      0               ;read error?
 274         jp      nz,wboot
 275
 276         pop     hl
 277         ld      de,128
 278         add     hl,de
 279         pop     de
 280         pop     bc
 281         dec     b
 282         jp      z,gocpm
 283
 284         inc     d
 285         ld      a,(bootspt)
 286         dec     a
 287         cp      d               ;if sector >= spt then change tracks
 288         jp      nc,load1
 289
 290         ld      d,0
 291         inc     c
 292         push    bc
 293         push    de
 294         push    hl
 295         ld      b,0
 296         call    settrk
 297         pop     hl
 298         pop     de
 299         pop     bc
 300         jp      load1
 301
 302 gocpm:
 303         ld      a,0c3h
 304         ld      (0),a
 305         ld      hl,wboote
 306         ld      (1),hl
 307         ld      (5),a
 308         ld      hl,bdos
 309         ld      (6),hl
 310
 311         ld      bc,buff
 312         call    setdma
 313         ld      a,(cdisk)
 314         ld      c,a
 315         jp      ccp
 316
 317 msgSel: db      13,10,"Sel: ",0
 318
 319 getdpb:
 320         ld      de,10
 321         add     hl,de
 322         ld      e,(hl)
 323         inc     hl
 324         ld      d,(hl)          ;de = dpb
 325         ret
 326
 327 seldsk:
 328         ld      a,c
 329         out     (15),a
 330
 331         ld      a,e             ;reselection bit
 332         rrca
 333         jp      c,getdph        ;skip, if disk already active
 334         ld      hl,0
 335         in      a,(15)          ;querry, if disk exists
 336         or      a
 337         ret     z
 338 getdph:
 339         ld      hl,drvtbl
 340         ld      b,0
 341         add     hl,bc
 342         add     hl,bc
 343         ld      a,(hl)          ;get table entry for selected disk
 344         inc     hl
 345         ld      h,(hl)
 346         ld      l,a
 347         or      h               ;return zero, if no entry (no disk)
 348         ret
 349
 350
 351 home:
 352         ld a,1 shl HOME_FUNC
 353         out (22),a
 354
 355         ld bc,0                 ; same as seek to track 0
 356 settrk:
 357         ld a,c
 358         out (16),a
 359         ld a,b
 360         out (17),a
 361         ret
 362
 363 setsec:
 364         ld a,c
 365         out (18),a
 366         ret
 367
 368 setdma:
 369         ld a,c
 370         out (20),a
 371         ld a,b
 372         out (21),a
 373         ret
 374
 375 read:
 376         ld a,1 shl READ_FUNC
 377         out (22),a
 378         in a,(22)
 379         and 1
 380         ret
 381
 382 write:
 383         ld      a,c
 384         and     3               ;mask write  type
 385         or      1 shl WRITE_FUNC
 386         out     (22),a
 387         in a,(22)
 388         and 1
 389         ret
 390
 391 sectran:
 392         ;translate sector bc using table at de, res into hl
 393         ld h,b
 394         ld l,c
 395         ld a,d
 396         or e
 397         ret z
 398         ex de,hl
 399         add hl,bc
 400         ld l,(hl)
 401         ld h,0
 402         ret
 403
 404 bcb:    dw      drvtbl
 405         dw      dirbuf
 406         dw      enddat
 407
 408 bootdsk:ds      1
 409 bootspt:ds      1
 410
 411         .8080
 412         endef
 413
 414         end
 415