v4.0/src/MAPPER/SCROLLUP.ASM

   1 ;
   2 page 60,132
   3 ;
   4 title CP/DOS VioScrollUp mapper
   5 ;
   6 vioxxx  segment byte public 'vio'
   7         assume  cs:vioxxx,ds:nothing,es:nothing,ss:nothing
   8 ;
   9 ; ************************************************************************* *
  10 ; *
  11 ; *      MODULE: VioScrollUp
  12 ; *
  13 ; *      FILE NAME: scrollup.asm
  14 ; *
  15 ; *      CALLING SEQUENCE:
  16 ; *
  17 ; *
  18 ; *             push    word    toprow
  19 ; *             push    word    leftcol
  20 ; *             push    word    botrow
  21 ; *             push    word    rightcol
  22 ; *             push    word    lines
  23 ; *             push@   dword   cell
  24 ; *             push    word    vio handle
  25 ; *             call    vioscrollup
  26 ; *
  27 ; *      MODULES CALLED:  BIOS Int 10h
  28 ; *
  29 ; *
  30 ; *
  31 ; *************************************************************************
  32
  33         public vioscrollup
  34         .sall
  35         .xlist
  36         include macros.inc
  37         .list
  38
  39 error_bvs_parameter equ 0002h
  40
  41 str     struc
  42 old_bp   dw      ?
  43 return   dd      ?
  44 handle   dw      ?        ; vio handle
  45 cell     dd      ?        ; cell to be written
  46 lines    dw      ?        ; number of blank lines
  47 rightcol dw      ?        ; right column
  48 botrow   dw      ?        ; bottom row
  49 leftcol  dw      ?        ; left column
  50 toprow   dw      ?        ; top row
  51 str     ends
  52
  53 vioscrollup proc   far
  54         Enter   VioScrollUp             ; save registers
  55
  56         mov     bx,[bp].lines           ; get number of blank lines
  57         cmp     bl,25                   ; check for validity
  58         jg      error                   ; jump if invalid
  59
  60         mov     al,bl
  61         jmp     ar02
  62
  63 ar01:   mov     al,00h
  64 ar02:   mov     ah,06h                  ; set scroll up function code
  65
  66         mov     bx,[bp].rightcol        ; get right col number
  67         cmp     bl,80                   ; check the validity
  68         jg      error                   ; branch if error
  69         mov     dl,bl                   ; right column number in DL
  70
  71         mov     bx,[bp].botrow          ; get bottom row
  72         cmp     bl,25                   ; check for validity
  73         jg      error                   ; branch if error
  74         mov     dh,bl                   ; bottom row in DH
  75
  76         mov     bx,[bp].leftcol         ; get left column number
  77         mov     cl,bl                   ; left column in CL
  78
  79         mov     bx,[bp].toprow          ; get top row number
  80         mov     ch,bl                   ; top row in CH
  81
  82         lds     si,[bp].cell            ; Set up cell in BX
  83         mov     bx,ds:[si]              ;                    *****************
  84 ;       cmp     bl,15                   ; check validity     ** assume good **
  85 ;       jg      error                   ; branch if error    ** attribute!  **
  86                                         ;                    *****************
  87         mov     bh,bl                   ; filler attribute in BH
  88         pushal                          ; Save registers in case int 10h
  89                                         ;   messes them up
  90         int     10h                     ; scrollup the display
  91
  92         popal
  93         sub     ax,ax                   ; set no error code
  94         jmp     exit                    ; return
  95
  96 error:  mov     ax,error_bvs_parameter  ; set error code
  97
  98 exit:   Mexit                           ; pop registers
  99         ret     size str - 6            ; return
 100
 101 vioscrollup endp
 102 vioxxx  ends
 103         end