cbios/utils.180

   1         title 'general utility routines'
   2
   3         ; i/o port init routines
   4
   5         public ioiniml,ioini1l          ;
   6
   7         ; math
   8
   9         public ijphl                    ; vectored CALL point
  10         public add_hla                  ; add a to hl
  11         public div32_16,div32_r         ; divide 32 bit by 16 bit number (rounded)
  12
  13         ; print utils
  14
  15         public ?pmsg                    ; print message
  16         public pr.idx                   ; print message from table indexed by <A>
  17         public pr.inln,pr.crlf          ; print message inline, print newline
  18         public phex2,phex4              ; print 2 digit hex <A> or 4 digit hex <HL>
  19         public pr.dec,pr.decl           ; print 16 or 32 bit decimal number
  20         public pr.errors                ; print BIOS disk error message header
  21
  22
  23
  24         extrn ?const,?conin,?cono
  25         extrn @adrv,@trk,@sect          ; used by disk error message
  26         extrn @op,@ermde
  27
  28 ;-------------------------------------------------------------------------------
  29
  30 cr      equ     13
  31 lf      equ     10
  32 bell    equ     7
  33
  34
  35         dseg
  36
  37 ;----------------------------------------------------------------------
  38 ; output bytes to consecutive portaddresses
  39 ;
  40 ;     hl: table with following structure:
  41 ;        db n, port1, val1, val2,... valn
  42 ;        db m, port1, val1, val2,... valm
  43 ;        ...
  44 ;        db 0 ; Terminate table
  45
  46 ioiniml:
  47         push    bc
  48         xor     a
  49 ioml_lp:
  50         ld      b,(hl)
  51         inc     hl
  52         cp      b
  53         jr      z,ioml_e
  54
  55         ld      c,(hl)
  56         inc     hl
  57         otimr
  58         jr      ioml_lp
  59 ioml_e:
  60         pop     bc
  61         ret
  62
  63 ;----------------------------------------------------------------------
  64 ; output bytes to ports
  65 ;
  66 ;     hl: tables of port,value pairs:
  67 ;         db n, port1,val1, port2,val2,... portn,valn
  68 ;         ...
  69 ;         db 0 ; Terminate table
  70
  71 ioini1l:
  72         push    bc
  73         jr      io1_nxt
  74 io1_lp:
  75         ld      c,(hl)          ;port address
  76         inc     hl
  77         otim
  78         jr      nz,io1_lp
  79 io1_nxt:
  80         ld      b,(hl)          ;count
  81         inc     hl
  82         inc     b
  83         djnz    io1_lp
  84
  85         pop     bc
  86         ret
  87
  88         cseg
  89
  90 ;--------------------------------------------------------------------
  91 ; vectored CALL point
  92
  93 ijphl:
  94         jp      (hl)
  95
  96         dseg
  97
  98 ;--------------------------------------------------------------------
  99 ; add a to hl
 100 ;
 101 ;    return:
 102 ;       hl = hl + a
 103 ;       Flags undefined
 104
 105 add_hla:
 106         add     a,l
 107         ld      l,a
 108         ret     nc
 109         inc     h
 110         ret
 111
 112 ;--------------------------------------------------------------------
 113 ; rounded div 32 by 16 bit
 114 ;
 115 ;       DEHL:   Dividend (x)
 116 ;       BC:     Divisor  (y)
 117 ;    return:
 118 ;       HLDE:   Rounded Quotient (q)
 119 ;       BC:     Remainder              (r)
 120
 121 div32_r:
 122         push bc
 123         srl     b               ;y/2
 124         rr      c
 125         add     hl,bc           ;low x + y/2
 126         pop     bc
 127         jr      nc,div_r1
 128         inc     de
 129 div_r1:
 130         ;fall thru
 131
 132 ;--------------------------------------------------------------------
 133 ; Divide 32 bit by 16
 134 ;
 135 ;    DEHL:      Dividend (x)
 136 ;    BC:        Divisor  (y)
 137 ;
 138 ;  return:
 139 ;    DEHL:      Quotient
 140 ;    BC:        Reminder
 141
 142 div32_16:
 143         exx                     ;low
 144         push    de              ;save alternate registers (de,bc)
 145         push    bc
 146         exx                     ;high
 147         push    hl              ;lx
 148         push    bc              ;ly
 149         ld      bc,0            ;bc  = hy = 0
 150         ld      h,b             ;hl  = hr = 0
 151         ld      l,c
 152                                 ;de = x, hl = r
 153         exx                     ;low
 154         pop     bc              ;bc' = ly
 155         ex      (sp),hl         ;hl' = lx, save alternate hl
 156         ld      de,0            ;de' = lr = 0
 157         ex      de,hl           ;de = x, hl = r
 158         exx                     ;high
 159         ld      a,32            ;count
 160 ;
 161 ; start:
 162 ;     de: x     (de: hx, de': lx)
 163 ;     bc: y     (bc: hy, bc': ly)
 164 ;     hl: 0
 165 ;
 166 div_lp:                         ;do
 167         exx                     ;    low
 168         ex      de,hl           ;    x
 169         add     hl,hl           ;    x <<= 1
 170         exx                     ;    high
 171         ex      de,hl           ;    x
 172         adc     hl,hl           ;    x <<= 1
 173         exx                     ;    low
 174         ex      de,hl           ;    r
 175         adc     hl,hl           ;    r <<= 1
 176         exx                     ;    high
 177         ex      de,hl           ;    r
 178         adc     hl,hl           ;    r <<= 1
 179         exx                     ;    low
 180         inc     de              ;    x/q += 1
 181         or      a               ;
 182         sbc     hl,bc           ;
 183         exx                     ;    high
 184         sbc     hl,bc           ;
 185         jr      nc,div_no_restore
 186         exx                     ;        low
 187         dec     de              ;
 188         add     hl,bc           ;        r += y
 189         exx                     ;        high
 190         adc     hl,bc           ;
 191
 192 div_no_restore:                 ;
 193         dec     a               ;
 194         jr      nz,div_lp       ;while (--count)
 195
 196 ; result:
 197 ;     de: q     (de: hq, de': lq)
 198 ;     hl: r     (hl: hr, hl': lr)
 199
 200         exx                     ;low
 201         ex      de,hl           ;hl = lq,  de = lr
 202
 203         ex      (sp),hl         ;lq
 204         push    de              ;lr
 205         exx                     ;high
 206         pop     bc              ;bc = lr
 207         pop     hl              ;de = lq
 208
 209         exx                     ;low
 210         pop     bc              ;restore alternate registers
 211         pop     de
 212         exx                     ;high
 213         ret
 214
 215 ;-------------------------------------------------------------------------------
 216 ; print message @<HL> up to a null
 217 ; saves <BC> & <DE>
 218
 219 ?pmsg:
 220         push    bc
 221         push    de
 222 pmsg$loop:
 223         ld      a,(hl)
 224         inc     hl
 225         or      a
 226         jr      z,pmsg$exit
 227         ld      c,a
 228         push    hl
 229         call    ?cono
 230         pop     hl
 231         jr      pmsg$loop
 232 pmsg$exit:
 233         pop     de
 234         pop     bc
 235         ret
 236
 237 ;-------------------------------------------------------------------------------
 238 ; print message from table @<HL>, indexed by <A>
 239 ; saves <BC> & <DE>
 240
 241 pr.idx:
 242         push    bc
 243         push    de
 244         push    hl              ; put pointer to first message on stack
 245         ld      e,a             ; save message number
 246         xor     a
 247         ld      b,a
 248         ld      c,a
 249         inc     e
 250 pdc_nxt_str:
 251         dec     e
 252         ex      (sp),hl
 253         jr      z,pdc_found
 254         ex      (sp),hl
 255         cpir
 256         cp      (hl)
 257         jr      nz,pdc_nxt_str
 258                                 ; End of List, msg not found.
 259                                 ; Print first msg.
 260 pdc_found:
 261         pop     hl
 262         call    ?pmsg
 263         pop     de
 264         pop     bc
 265         ret
 266
 267 ;-------------------------------------------------------------------------------
 268 ; print message inline up to a null
 269 ; saves all registers
 270
 271 pr.inln:
 272         ex      (sp),hl
 273         push    af
 274         call    ?pmsg
 275         pop     af
 276         ex      (sp),hl
 277         ret
 278
 279 ;-------------------------------------------------------------------------------
 280 ; print <CR><LF>
 281 ; saves all registers
 282
 283 pr.crlf:
 284         call    pr.inln
 285         db      cr,lf,0
 286         ret
 287
 288 ;-------------------------------------------------------------------------------
 289 ; print hl as a 4 digit hexadecimal number
 290 ; saves all registers
 291
 292 phex4:
 293         ld a,h
 294         call phex2
 295         ld a,l
 296         ; fall thru
 297
 298 ;-------------------------------------------------------------------------------
 299 ; print a as a 2 digit hexadecimal number
 300 ; saves all registers
 301
 302 phex2:
 303         push    af
 304         rra
 305         rra
 306         rra
 307         rra
 308         call    print.digit
 309         pop     af
 310
 311 print.digit:
 312         push    hl
 313         push    de
 314         push    bc
 315         push    af
 316         and     00fh
 317         cp      10
 318         jr      c,prd_1
 319         add     a,007h
 320 prd_1:
 321         add     a,'0'
 322
 323         ld      c,a
 324         call    ?cono
 325         pop     af
 326         pop     bc
 327         pop     de
 328         pop     hl
 329         ret
 330
 331
 332 ;-------------------------------------------------------------------------------
 333 ; print decimal 16 bit number from HL
 334 ;
 335 ;       HL: unsigned binary number to print
 336 ;        C: minimum print field width
 337 ;           number is prined right-aligned
 338 ;        B: pad character, typically ' ' or '0'
 339
 340 pr.dec:
 341         push    de
 342         ld      de,0
 343         call    pr.decl
 344         pop     de
 345         ret
 346
 347 ;-------------------------------------------------------------------------------
 348 ; print decimal 32 bit number from DEHL
 349 ;
 350 ;       DEHL: unsigned binary number to print
 351 ;          C: minimum print field width
 352 ;             number is prined right-aligned
 353 ;          B: pad character, typically ' ' or '0'
 354
 355 pr.decl:
 356         push    bc              ;save width and fillchar
 357         push    bc
 358         exx                     ;(alt)
 359         ex      (sp),hl         ;save hl', get width and fill
 360         push    de              ;save de'
 361
 362         xor     a
 363         ld      d,a             ;clear counter
 364         ld      e,a
 365         push    af              ; string terminator
 366         inc     sp
 367
 368 prd_divloop:                    ;do
 369         exx                     ;    (main)
 370         ld      bc,10           ;
 371         call    div32_16        ;    get a digit
 372         ld      a,c             ;
 373         add     a,'0'           ;    make it printable
 374         push    af              ;
 375
 376         ld      a,h             ;
 377         or      l               ;
 378         or      d               ;
 379         or      e               ;
 380         exx                     ;    (alt)
 381         inc     sp              ;
 382         inc     de              ;
 383         jr      nz,prd_divloop  ;
 384
 385 prd_filloop:                    ;h=filler, l=field width
 386         ld      a,e
 387         cp      l
 388         jr      nc,prd_out
 389         push    hl
 390         inc     sp
 391         inc     de
 392         jr      prd_filloop
 393 prd_out:
 394         ld      hl,0
 395         add     hl,sp           ;ptr to beginning of number string (hl==0 here)
 396         call    ?pmsg
 397         ex      de,hl
 398         add     hl,sp
 399         ld      sp,hl
 400         inc     sp              ;remove string terminator
 401         pop     de
 402         pop     hl
 403         exx                     ;(main)
 404         pop     bc
 405         ret
 406
 407
 408 ;-------------------------------------------------------------------------------
 409
 410 ?pderr:
 411         ld      hl,drive$msg
 412         call    ?pmsg           ; error header
 413         ld      a,(@adrv)
 414         add     a,'A'
 415         ld      c,a
 416         call    ?cono           ; drive code
 417         ld      hl,track$msg
 418         call    ?pmsg           ; track header
 419         ld      c,0
 420         ld      hl,(@trk)
 421         call    pr.dec          ; track number
 422         ld      hl,sector$msg
 423         call    ?pmsg           ; sector header
 424         ld      hl,(@sect)
 425         jp      pr.dec          ; sector number
 426
 427         ; error message components
 428 drive$msg:      db      cr,lf,bell,'BIOS Error on ',0
 429 track$msg:      db      ': T-',0
 430 sector$msg:     db      ', S-',0
 431
 432
 433 ;-------------------------------------------------------------------------------
 434 ; get console input, echo it, and shift to upper case
 435 ; save hl,de,bc
 436
 437 uciecho:
 438         push    hl
 439         push    de
 440         push    bc
 441 u$c0:
 442         call    ?const
 443         or      a
 444         jr      z,u$c1          ; see if any char already struck
 445         call    ?conin
 446         jr      u$c0            ; yes, eat it and try again
 447 u$c1:
 448         call    ?conin
 449         push    af
 450         ld      c,a
 451         cp      ' '-1
 452         call    nc,?cono
 453         pop     af
 454         pop     bc
 455         pop     de
 456         pop     hl
 457         cp      'a'
 458         ret     c
 459         sub     'a'-'A'         ; make upper case
 460         ret
 461
 462 ;-------------------------------------------------------------------------------
 463 ;
 464
 465 pr.errors:
 466
 467         ; suppress error message if BDOS
 468         ; is returning errors to application...
 469
 470         ld      a,(@ermde)
 471         inc     a
 472         jr      nz,pre1
 473         dec     a               ;return NZ, if @ermde == 0FFH
 474         ret
 475 pre1:
 476         push    hl
 477         ld      hl,pre2
 478         ex      (sp),hl
 479         push    hl
 480
 481         ; Had permanent error, print message like:
 482         ; BIOS Err on d: T-nn, S-mm, <operation> <type>, Retry ?
 483
 484         call    ?pderr          ; print message header
 485
 486         ld      hl,op$msg
 487         ld      a,(@op)
 488         jp      pr.idx          ; last function (read or write)
 489
 490 pre2:
 491                                 ; prompt for retry
 492         call    pr.inln
 493         db      ' Retry (Y/N) ? ',0
 494
 495         call    uciecho         ; get operator response
 496         cp      'Y'
 497         ret                     ; return Z-flag for yes
 498
 499
 500 op$msg:
 501         db      ', Unknown op, ',0
 502         db      ', Read, ',0
 503         db      ', Write, ',0
 504         db      0
 505
 506         end