cbios/utils.180

   1 ==== BASE ====
   2         title 'general utility routines'
   3
   4         ; i/o port init routines
   5
   6         public ioiniml,ioini1l          ;
   7
   8         ; math
   9
  10         public ijphl                    ; vectored CALL point
  11         public add_hla                  ; add a to hl
  12         public div32_16,div32_r         ; divide 32 bit by 16 bit number (rounded)
  13
  14         ; print utils
  15
  16         public ?pmsg                    ; print message
  17         public pr.idx                   ; print message from table indexed by <A>
  18         public pr.inln,pr.crlf          ; print message inline, print newline
  19         public phex2,phex4              ; print 2 digit hex <A> or 4 digit hex <HL>
  20         public pr.dec,pr.decl           ; print 16 or 32 bit decimal number
  21         public pr.errors                ; print BIOS disk error message header
  22
  23
  24
  25         extrn ?const,?conin,?cono
  26         extrn @adrv,@trk,@sect          ; used by disk error message
  27         extrn @op,@ermde
  28
  29 ;-------------------------------------------------------------------------------
  30
  31 cr      equ     13
  32 lf      equ     10
  33 bell    equ     7
  34
  35
  36         dseg
  37
  38 ;----------------------------------------------------------------------
  39 ; output bytes to consecutive portaddresses
  40 ;
  41 ;     hl: table with following structure:
  42 ;        db n, port1, val1, val2,... valn
  43 ;        db m, port1, val1, val2,... valm
  44 ;        ...
  45 ;        db 0 ; Terminate table
  46
  47 ioiniml:
  48         push    bc
  49         xor     a
  50 ioml_lp:
  51         ld      b,(hl)
  52         inc     hl
  53         cp      b
  54         jr      z,ioml_e
  55
  56         ld      c,(hl)
  57         inc     hl
  58         otimr
  59         jr      ioml_lp
  60 ioml_e:
  61         pop     bc
  62         ret
  63
  64 ;----------------------------------------------------------------------
  65 ; output bytes to ports
  66 ;
  67 ;     hl: tables of port,value pairs:
  68 ;         db n, port1,val1, port2,val2,... portn,valn
  69 ;         ...
  70 ;         db 0 ; Terminate table
  71
  72 ioini1l:
  73         push    bc
  74         jr      io1_nxt
  75 io1_lp:
  76         ld      c,(hl)          ;port address
  77         inc     hl
  78         otim
  79         jr      nz,io1_lp
  80 io1_nxt:
  81         ld      b,(hl)          ;count
  82         inc     hl
  83         inc     b
  84         djnz    io1_lp
  85
  86         pop     bc
  87         ret
  88 ;--------------------------------------------------------------------
  89 ; vectored CALL point
  90
  91 ijphl:
  92         jp      (hl)
  93
  94 ;--------------------------------------------------------------------
  95 ; add a to hl
  96 ;
  97 ;    return:
  98 ;       hl = hl + a
  99 ;       Flags undefined
 100
 101 add_hla:
 102         add     a,l
 103         ld      l,a
 104         ret     nc
 105         inc     h
 106         ret
 107
 108 ;--------------------------------------------------------------------
 109 ; rounded div 32 by 16 bit
 110 ;
 111 ;       DEHL:   Dividend (x)
 112 ;       BC:     Divisor  (y)
 113 ;    return:
 114 ;       HLDE:   Rounded Quotient (q)
 115 ;       BC:     Remainder              (r)
 116
 117 div32_r:
 118         push bc
 119         srl     b               ;y/2
 120         rr      c
 121         add     hl,bc           ;low x + y/2
 122         pop     bc
 123         jr      nc,div_r1
 124         inc     de
 125 div_r1:
 126         ;fall thru
 127
 128 ;--------------------------------------------------------------------
 129 ; Divide 32 bit by 16
 130 ;
 131 ;    DEHL:      Dividend (x)
 132 ;    BC:        Divisor  (y)
 133 ;
 134 ;  return:
 135 ;    DEHL:      Quotient
 136 ;    BC:        Reminder
 137
 138 div32_16:
 139         exx                     ;low
 140         push    de              ;save alternate registers (de,bc)
 141         push    bc
 142         exx                     ;high
 143         push    hl              ;lx
 144         push    bc              ;ly
 145         ld      bc,0            ;bc  = hy = 0
 146         ld      h,b             ;hl  = hr = 0
 147         ld      l,c
 148                                 ;de = x, hl = r
 149         exx                     ;low
 150         pop     bc              ;bc' = ly
 151         ex      (sp),hl         ;hl' = lx, save alternate hl
 152         ld      de,0            ;de' = lr = 0
 153         ex      de,hl           ;de = x, hl = r
 154         exx                     ;high
 155         ld      a,32            ;count
 156 ;
 157 ; start:
 158 ;     de: x     (de: hx, de': lx)
 159 ;     bc: y     (bc: hy, bc': ly)
 160 ;     hl: 0
 161 ;
 162 div_lp:                         ;do
 163         exx                     ;    low
 164         ex      de,hl           ;    x
 165         add     hl,hl           ;    x <<= 1
 166         exx                     ;    high
 167         ex      de,hl           ;    x
 168         adc     hl,hl           ;    x <<= 1
 169         exx                     ;    low
 170         ex      de,hl           ;    r
 171         adc     hl,hl           ;    r <<= 1
 172         exx                     ;    high
 173         ex      de,hl           ;    r
 174         adc     hl,hl           ;    r <<= 1
 175         exx                     ;    low
 176         inc     de              ;    x/q += 1
 177         or      a               ;
 178         sbc     hl,bc           ;
 179         exx                     ;    high
 180         sbc     hl,bc           ;
 181         jr      nc,div_no_restore
 182         exx                     ;        low
 183         dec     de              ;
 184         add     hl,bc           ;        r += y
 185         exx                     ;        high
 186         adc     hl,bc           ;
 187
 188 div_no_restore:                 ;
 189         dec     a               ;
 190         jr      nz,div_lp       ;while (--count)
 191
 192 ; result:
 193 ;     de: q     (de: hq, de': lq)
 194 ;     hl: r     (hl: hr, hl': lr)
 195
 196         exx                     ;low
 197         ex      de,hl           ;hl = lq,  de = lr
 198
 199         ex      (sp),hl         ;lq
 200         push    de              ;lr
 201         exx                     ;high
 202         pop     bc              ;bc = lr
 203         pop     hl              ;de = lq
 204
 205         exx                     ;low
 206         pop     bc              ;restore alternate registers
 207         pop     de
 208         exx                     ;high
 209         ret
 210
 211 ;-------------------------------------------------------------------------------
 212 ; print message @<HL> up to a null
 213 ; saves <BC> & <DE>
 214
 215 ?pmsg:
 216         push    bc
 217         push    de
 218 pmsg$loop:
 219         ld      a,(hl)
 220         inc     hl
 221         or      a
 222         jr      z,pmsg$exit
 223         ld      c,a
 224         push    hl
 225         call    ?cono
 226         pop     hl
 227         jr      pmsg$loop
 228 pmsg$exit:
 229         pop     de
 230         pop     bc
 231         ret
 232
 233 ;-------------------------------------------------------------------------------
 234 ; print message from table @<HL>, indexed by <A>
 235 ; saves <BC> & <DE>
 236
 237 pr.idx:
 238         push    bc
 239         push    de
 240         push    hl              ; put pointer to first message on stack
 241         ld      e,a             ; save message number
 242         xor     a
 243         ld      b,a
 244         ld      c,a
 245         inc     e
 246 pdc_nxt_str:
 247         dec     e
 248         ex      (sp),hl
 249         jr      z,pdc_found
 250         ex      (sp),hl
 251         cpir
 252         cp      (hl)
 253         jr      nz,pdc_nxt_str
 254                                 ; End of List, msg not found.
 255                                 ; Print first msg.
 256 pdc_found:
 257         pop     hl
 258         call    ?pmsg
 259         pop     de
 260         pop     bc
 261         ret
 262
 263 ;-------------------------------------------------------------------------------
 264 ; print message inline up to a null
 265 ; saves all registers
 266
 267 pr.inln:
 268         ex      (sp),hl
 269         push    af
 270         call    ?pmsg
 271         pop     af
 272         ex      (sp),hl
 273         ret
 274
 275 ;-------------------------------------------------------------------------------
 276 ; print <CR><LF>
 277 ; saves all registers
 278
 279 pr.crlf:
 280         call    pr.inln
 281         db      cr,lf,0
 282         ret
 283
 284 ;-------------------------------------------------------------------------------
 285 ; print hl as a 4 digit hexadecimal number
 286 ; saves all registers
 287
 288 phex4:
 289         ld a,h
 290         call phex2
 291         ld a,l
 292         ; fall thru
 293
 294 ;-------------------------------------------------------------------------------
 295 ; print a as a 2 digit hexadecimal number
 296 ; saves all registers
 297
 298 phex2:
 299         push    af
 300         rra
 301         rra
 302         rra
 303         rra
 304         call    print.digit
 305         pop     af
 306
 307 print.digit:
 308         push    hl
 309         push    de
 310         push    bc
 311         push    af
 312         and     00fh
 313         cp      10
 314         jr      c,prd_1
 315         add     a,007h
 316 prd_1:
 317         add     a,'0'
 318
 319         ld      c,a
 320         call    ?cono
 321         pop     af
 322         pop     bc
 323         pop     de
 324         pop     hl
 325         ret
 326
 327
 328 ;-------------------------------------------------------------------------------
 329 ; print decimal 16 bit number from HL
 330 ;
 331 ;       HL: unsigned binary number to print
 332 ;        C: minimum print field width
 333 ;           number is prined right-aligned
 334 ;        B: pad character, typically ' ' or '0'
 335
 336 pr.dec:
 337         push    de
 338         ld      de,0
 339         call    pr.decl
 340         pop     de
 341         ret
 342
 343 ;-------------------------------------------------------------------------------
 344 ; print decimal 32 bit number from DEHL
 345 ;
 346 ;       DEHL: unsigned binary number to print
 347 ;          C: minimum print field width
 348 ;             number is prined right-aligned
 349 ;          B: pad character, typically ' ' or '0'
 350
 351 pr.decl:
 352         push    bc              ;save width and fillchar
 353         push    bc
 354         exx                     ;(alt)
 355         ex      (sp),hl         ;save hl', get width and fill
 356         push    de              ;save de'
 357
 358         xor     a
 359         ld      d,a             ;clear counter
 360         ld      e,a
 361         push    af              ; string terminator
 362         inc     sp
 363
 364 prd_divloop:                    ;do
 365         exx                     ;    (main)
 366         ld      bc,10           ;
 367         call    div32_16        ;    get a digit
 368         ld      a,c             ;
 369         add     a,'0'           ;    make it printable
 370         push    af              ;
 371
 372         ld      a,h             ;
 373         or      l               ;
 374         or      d               ;
 375         or      e               ;
 376         exx                     ;    (alt)
 377         inc     sp              ;
 378         inc     de              ;
 379         jr      nz,prd_divloop  ;
 380
 381 prd_filloop:                    ;h=filler, l=field width
 382         ld      a,e
 383         cp      l
 384         jr      nc,prd_out
 385         push    hl
 386         inc     sp
 387         inc     de
 388         jr      prd_filloop
 389 prd_out:
 390         ld      hl,0
 391         add     hl,sp           ;ptr to beginning of number string (hl==0 here)
 392         call    ?pmsg
 393         ex      de,hl
 394         add     hl,sp
 395         ld      sp,hl
 396         inc     sp              ;remove string terminator
 397         pop     de
 398         pop     hl
 399         exx                     ;(main)
 400         pop     bc
 401         ret
 402
 403
 404 ;-------------------------------------------------------------------------------
 405
 406 ?pderr:
 407         ld      hl,drive$msg
 408         call    ?pmsg           ; error header
 409         ld      a,(@adrv)
 410         add     a,'A'
 411         ld      c,a
 412         call    ?cono           ; drive code
 413         ld      hl,track$msg
 414         call    ?pmsg           ; track header
 415         ld      c,0
 416         ld      hl,(@trk)
 417         call    pr.dec          ; track number
 418         ld      hl,sector$msg
 419         call    ?pmsg           ; sector header
 420         ld      hl,(@sect)
 421         jp      pr.dec          ; sector number
 422
 423         ; error message components
 424 drive$msg:      db      cr,lf,bell,'BIOS Error on ',0
 425 track$msg:      db      ': T-',0
 426 sector$msg:     db      ', S-',0
 427
 428
 429 ;-------------------------------------------------------------------------------
 430 ; get console input, echo it, and shift to upper case
 431 ; save hl,de,bc
 432
 433 uciecho:
 434         push    hl
 435         push    de
 436         push    bc
 437 u$c0:
 438         call    ?const
 439         or      a
 440         jr      z,u$c1          ; see if any char already struck
 441         call    ?conin
 442         jr      u$c0            ; yes, eat it and try again
 443 u$c1:
 444         call    ?conin
 445         push    af
 446         ld      c,a
 447         cp      ' '-1
 448         call    nc,?cono
 449         pop     af
 450         pop     bc
 451         pop     de
 452         pop     hl
 453         cp      'a'
 454         ret     c
 455         sub     'a'-'A'         ; make upper case
 456         ret
 457
 458 ;-------------------------------------------------------------------------------
 459 ;
 460
 461 pr.errors:
 462
 463         ; suppress error message if BDOS
 464         ; is returning errors to application...
 465
 466         ld      a,(@ermde)
 467         inc     a
 468         jr      nz,pre1
 469         dec     a               ;return NZ, if @ermde == 0FFH
 470         ret
 471 pre1:
 472         push    hl
 473         ld      hl,pre2
 474         ex      (sp),hl
 475         push    hl
 476
 477         ; Had permanent error, print message like:
 478         ; BIOS Err on d: T-nn, S-mm, <operation> <type>, Retry ?
 479
 480         call    ?pderr          ; print message header
 481
 482         ld      hl,op$msg
 483         ld      a,(@op)
 484         jp      pr.idx          ; last function (read or write)
 485
 486 pre2:
 487                                 ; prompt for retry
 488         call    pr.inln
 489         db      ' Retry (Y/N) ? ',0
 490
 491         call    uciecho         ; get operator response
 492         cp      'Y'
 493         ret                     ; return Z-flag for yes
 494
 495
 496 op$msg:
 497         db      ', Unknown op, ',0
 498         db      ', Read, ',0
 499         db      ', Write, ',0
 500         db      0
 501
 502         end