Power-Programmierung/CD1.mdf/assemblr/library/asmlib/input.doc

Text File | 1994-05-03 | 30KB | 855 lines

********************************  INPUT  ************************************

ASMLIB Input subroutines (C) Copyright 1991 - 1994 Douglas Herr
all rights reserved

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A$EDIT:      editor module used by TEdit and GEdit.
             Must be called by GEdit or TEdit
Source:      a$edit.asm (getkey.asm, isdigit.asm, toupper.asm, tolower.asm)

             TEdit and GEdit edit a string on a single row of the screen
             (without word wrap).  Strings longer than the column width of
             the screen are scrolled left or right as required.  A public
             byte in A$EDIT's data area, EWIDTH, establishes the effective
             screen width limit.  EWIDTH is a not-to-exceed limit; if the
             actual screen width is less than EWIDTH, EWIDTH is ignored
             and the actual screen width is used instead.  ASMLIB's default
             EWIDTH is 132.

             A$EDIT commands for both TEdit and GEdit are:

             Ctrl+left arrow = word left
             Ctrl+right arrow = word right
             Ctrl+end = clear to end of string
             Home = go to start of string
             End = go to end of string


             Option bits, passed to GEdit or TEdit in register AL, are:

             Option 1 = upper case input
             Option 2 = lower case input
             Option 1 OR 2 = digits only input
             Option 4 = exit when any non-editing extended key is pressed
                        (example: F-keys, Alt+key; see TEdit)

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CLEARKEY:    clears the keyboard's 'type-ahead' buffer
             Uses BIOS functions to remove all keys in the buffer.
Source:      clearkey.asm

Call with:   no parameters
Returns:     nothing
Uses:        nothing
Supports:    standard and enhanced keyboards
Example:     call   clearkey



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GEDIT:       string editor for graphics modes
             See also TEdit for text modes, A$EDIT for general information
Source:      gedit.asm (a$edit.asm, gprint.asm, a$graph.asm, gcursor.asm,
                        strspace.asm, heap.asm)

Call with:   DS:[SI] pointing to string buffer; may include a default string
             DS:[DX] pointing to x- & y-coordinates
             assumes DS:@data
             CX = byte size of buffer
             AL = option bits (see A$EDIT)
             You must initialize the near heap before calling GEdit.
             GEdit only works with DrawMode 1 or -1 (see DrawMode in
             GRAPHICS.DOC).  GEdit forces drawmode to 1 or -1 and restores
             the previous drawmode on exit.
Returns:     AX = last key pressed (see getkey for key codes)
             CX = new string length
Uses:        AX, CX, flags
Supports:    all ASMLIB graphics modes
Example:

.data
x       dw 8                      ; x-coordinate (pixels from left edge)
y       dw 100                    ; y-coordinate (pixels from top of screen)
extrn   ewidth:byte               ; byte in A$EDIT used to limit columns
                                  ; displayed
.code
        .
        .
        .
        mov   ax,@data
        mov   ds,ax
        assume  ds:@data
        mov   ewidth,40           ; there's stuff on the right side of
                                  ; the screen that should be left alone

        lea   si,string_buffer    ; near address of string buffer
        mov   cx,len_buffer       ; byte length of buffer for the string
        mov   al,0                ; nothing tricky
        lea   dx,x                ; point to x & y coordinates
                                  ; see GPrint for explanation of x and y
        call  gedit



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GETKEY:      returns next key pressed
Source:      getkey.asm

Call with:   no parameters
Returns:     AL = ASCII key code
             AH = 0 if normal key
             AH = 1 if extended key code (such as function keys)
Uses:        AX
             Uses BIOS functions; supports enhanced keyboard if present
Supports:    standard and enhanced keyboards
Example:     call  getkey
             shr   ah,1            ; a function key?
             jc    function_key    ; jump if so


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GPICKF:      pick a file from a list of filenames
             GPickF pops a window on the screen and displays filenames
             matching an input filespec mask.  One filename may be selected
             with cursor keys or with hotkeys.  When Esc, Enter or ^C is
             pressed, GPickF restores the screen and returns the selected
             filename to the calling program.
             Unused memory must be released by STARTUP (see STARTUP.ASM or
             TINY.ASM).  Also requires near heap (see HINIT).
             See also MenuOption.
Source:      gpickf.asm (filelist.asm, $gpick.asm, a$menu.asm, $graph.asm)

Call with:   DS:[SI] pointing to filespec mask
             BX = initial selection (0 = first filename)
             CX = file attribute mask
             DS:[DX] pointing to upper left corner of menu box
             assumes DS:DGROUP
Returns:     AX = last key pressed
             ES:[BX] points to filename selected
             CX = maximum length of filename
Uses:        AX, BX, CX, ES
Supports:    all ASMLIB graphics modes
Example:     see PICKF

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GPICKSTR:    pick a string from a list of ASCIIZ strings
Source:      gpickstr.asm ($gpick.asm, $strlist.asm, a$menu.asm, $graph.asm)

Call with:   DS:[SI] pointing to list of ASCIIZ strings
             BX = initial cursor position
             DS:[DX] pointing to (x,y) coordinates of upper left corner
               of selection box

             GPickStr pops a window on the screen and displays the list
             of strings.  One string may be selected with cursor keys
             or with hotkeys.  When Esc, Enter or ^C is pressed, GPickStr
             restores the screen and returns a string index number.
             Unused memory must be released by STARTUP (see STARTUP.ASM and
             TINY.ASM), and the near heap must be initialized (see HINIT).
             See also MenuOption.  Maximum number of choices: 255

Returns:     AX = last key pressed
             BX = string number selected (first string = 0)
Uses:        AX, BX
Supports:    all ASMLIB graphics modes
Example:     see PICKSTR


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ISALPHA:     determines if a keycode returned by GetKey is a letter from
             A-Z or a-z.
Source:      isalpha.asm

Call with:   AX = keycode returned by GetKey.
Returns:     if CF = 0, keycode is a character from A-Z or a-z
             if CF = 1, keycode is not a character from A-Z or a-z
             AX is not changed
Uses:        CF
Example:     call   getkey       ; get next keystroke
             call   isalpha
             jc     not_alpha


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ISDIGIT:     determines if a keycode returned by GetKey is the ASCII code
             for the numeric characters 0-9
Source:      isdigit.asm

Call with:   AX = keycode returned by GetKey.
Returns:     if CF = 0, keycode is a character from 0-9
             if CF = 1, keycode is not a character from 0-9
             AX is not changed
Uses:        CF
Example:     call   getkey       ; get next keystroke
             call   isdigit      ; I want numbers only
             jc     not_a_number



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ISLOWER:     determine if a keycode returned by GetKey is lower case
Source:      islower.asm

ISUPPER:     determine if a keycode returned by GetKey is upper case
Source:      isupper.asm

Call with:   AX = keycode returned by GetKey.
Returns:     if CF = 0, keycode is a character from A-Z or a-z
             if CF = 1, keycode is not a character from A-Z or a-z
             AX is not changed
Uses:        CF
Example:     call   getkey       ; get next keystroke
             call   isupper      ; is it upper case?
             jc     not_upper    ; no; could be lower case



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JANEIN:      German language version of YesNo
             waits for 'J' or 'N' key to be pressed
Source:      janein.asm

Call with:   no parameters
             Key pressed may be upper or lower case.  Upper case is
             returned.  Uses BIOS functions
Returns:     AX = 'J' or AX = 'N'
             future version will also return ^C
Uses:        AX
Example:

include asm.inc

extrn   JaNein:proc

.code
        .
        .
        .
        call  JaNein



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KEYIFWAITING:Returns first key if one is waiting in the keyboard buffer,
             or returns with no keycode if no keypress is waiting.
Source:      kifwait.asm (getkey.asm)

Call with:   no parameters
Returns:     AX = 0 if no key waiting
             AX = keycode if one is waiting in the buffer.  Uses BIOS.
Uses:        AX
Example:     call  keyifwaiting



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KEYORBUTTON: waits for first keypress or mouse button click
Source:      mouse.asm (getkey.asm)

Call with:   no parameters
             If a keypress is waiting in the keyboard buffer before
             this subroutine is called, the keycode is returned to
             the calling program without checking mouse button status.
Returns:     AX = keycode, BX = mouse button code (see MouseStatus)
Uses:        AX, BX
Supports:    2- or 3-button mouse, standard or enhanced keyboard
Example:     call   keyorbutton


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KEYWAITING:  Determines if a key is waiting in the keyboard buffer.
             Does not remove the key code from the buffer.  Uses BIOS.
Source:      getkey.asm

Call with:   no parameters
Returns:     AX = 0 if no key waiting
             AX = 1 if key waiting
Uses:        AX
Supports:    standard or enhanced keyboard
Example:     call   keywaiting
             or     ax,ax        ; has a key been pressed?
             jz     no_key       ; nope, not yet


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MENUOPTION:  options for PULLDOWN, PICKF, GPICKF, PICKSTR and GPICKSTR
Source:      a$menu.asm

Call with:   AX = option value
             BX = option number

             If you do not specify any options or if you call MenuOption
             with AX = 0, default values are assumed.

             options available are:           defaults:
               0 = normal text color            07h
               1 = current selection color      70h
               2 = list box color               0Fh
               3 = hotkey color                 0Fh         (1)
               4 = optional quitkey             no quitkey  (2)
               5 = exit when hotkey pressed     00h         (3)
               6 = box frame type (see WFRAME)  -1          (4)

NOTE: DEFAULT COLORS MAY NOT BE SUITABLE FOR SOME GRAPHICS MODES

(1) the first upper-case letter in each string is that string's hotkey
    no upper-case character = no hotkey
(2) the quitkey value is a keycode returned by GetKey
(3) use AX = -1 for exit when hotkey pressed, AX = 0 to disable
(4) text modes only

Returns:     nothing
Uses:        nothing
Supports:    GPickF, GPickStr, PullDown, PickF, PickStr menu systems
Example:

include   asm.inc
extrn     menuoption:proc, pulldown:proc

.code
          .
          .
          .
          mov   bx,0         ; text color
          mov   ax,23        ; white w/ blue background
                             ; in graph modes, this would be
                             ; MOV  AX,0107h  (see GCOLOR in GRAPHICS.DOC)
          call  menuoption




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MOUSELIMIT:  limits mouse's range of motion
Source:      mouse.asm

Call with:   DS:[BX] pointing to pixel coordinates of minimum and maximum
             x and y limits.  X-limits are the horizontal dimension and
             y-limits are the vertical dimension.
Returns:     nothing
Uses:        nothing
Example:

.data

x0    dw 30
y0    dw 15
x1    dw 620
y1    dw 250

.code
       .
       .
       .
      mov    ax,@data      ; you don't need to do this stuff after
      mov    ds,ax         ; your startup code unless you've messed with
      assume ds:@data      ; DS somewhere earlier in the program

      lea    bx,x          ; DS:[BX] points to limits
      call   mouselimit



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MOUSEPOS:    sets the mouse's position
Source:      mouse.asm

Call with:   DS:[DX] pointing to desired x- and y-coordinates
             Note that mouse coordinates are expressed as a pixel location
             as with graphics mode, even if the system is in text mode
Returns:     nothing
Uses:        nothing
Example:

.data

x     dw 100
y     dw 25

.code
      .
      .
      .
      mov    ax,@data      ; you don't need to do this stuff after
      mov    ds,ax         ; your startup code unless you've messed with
      assume ds:@data      ; DS somewhere earlier in the program

      lea    dx,x          ; DS:[DX] points to desired position
      call   mousepos


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MOUSESTATUS: determine mouse position & buttons pressed
Source:      mouse.asm

Call with:   no parameters
Returns:     if ZF = 1, no buttons are pressed
             if ZF = 0, BX = button code
              BX bit 0 if set = left button is down
              BX bit 1 if set = right button is down
              BX bit 2 if set = center button is down
             CX = horizontal (x) coordinate
             DX = vertical (y) coordinate
             Note that mouse positions are expressed as a pixel location
             as with graphics mode, even if the system is in text mode
Uses:        BX, CX, DX, flags
Example:     call  mousestatus
             jz    no_buttons     ; no buttons pressed if ZF = 1



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OUINON:      French language version of YesNo
             waits for 'O' or 'N' key to be pressed
Source:      ouinon.asm

Call with:   no parameters
             Key pressed may be upper or lower case.  Upper case is
             returned.  Uses BIOS functions
Returns:     AX = 'O' or AX = 'N'
             future version will also return ^C
Uses:        AX
Example:

include asm.inc

extrn   OuiNon:proc

.code
        .
        .
        .
        call  OuiNon





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PICKF:       pick a file from a list of filenames
             PickF pops a window on the screen and displays filenames
             matching an input filespec mask.  One filename may be selected
             with cursor keys or with hotkeys.  When Esc, Enter or ^C is
             pressed, PickF restores the screen and returns the selected
             filename to the calling program.
             Unused memory must be released by STARTUP (see STARTUP.ASM).
             PickF allocates a block of DOS memory which should be released
             after you are done with it.  See example.
             See also MenuOption.
Source:      pickf.asm ($pick.asm, $listw.asm, m$putw.asm, filelist.asm,
                          dosalloc.asm, wsave.asm, a$menu.asm)

Call with:   DS:[SI] pointing to filespec mask
             BX = initial cursor position
             CX = file attribute mask
             DH = top screen row for list (centered if DH = 0FFh)
             DL = left screen column for list (centered if DL = 0FFh)
Returns:     if CF = 0, AX = last key pressed
                        ES:[BX] points to filename selected
                        CX = maximum length of filename
             if CF = 1, no filenames match input filespec
Uses:        AX, BX, CX, ES, CF
Supports:    text mode
Example:

include   asm.inc

public    myproc
extrn     pickf:proc

.data
filespec db '*.asm',0            ; search for ASM source code

.code
; program fragment assumes DS:@data
        .
        .
        .
        lea     si,filespec
        mov     bx,0             ; start at top of list
        xor     dx,dx            ; upper left corner of screen
        mov     cx,0             ; normal files only
        call    pickf
        cmp     ax,0Dh           ; was Enter the last key pressed?
        jne     abort            ;  nope - someone wants out
        call    strndup          ;  yup - copy filename to near heap
        mov     ah,49h
        int     21h              ; release the filename buffer


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PICKSTR:     pick a string from a list of ASCIIZ strings
Source:      pickstr.asm ($pick.asm, m$putw.asm, $strlist.asm, $listw.asm,
                          dosalloc.asm, wsave.asm, a$menu.asm)

Call with:   DS:[SI] pointing to list of ASCIIZ strings
             BX = initial cursor position
             DH = top screen row for list (centered if DH = 0FFh)
             DL = left screen column for list (centered if DL = 0FFh)

             PickStr pops a window on the screen and displays the list
             of strings.  One string may be selected with cursor keys
             or with hotkeys.  When Esc, Enter or ^C is pressed, PickStr
             restores the screen and returns a string index number.
             Unused memory must be released by STARTUP (see STARTUP.ASM).
             See also MenuOption.  Maximum number of choices: 255

Returns:     AX = last key pressed
             BX = string number selected (first string = 0)
Uses:        AX, BX
Supports:    text mode
Example:

include   asm.inc

public    myproc
extrn     pickstr:proc

.data
string1   db 'January',0
          db 'February',0
          db 'March',0
          db 'April',0
          db 'May',0
          db 'June',0
          db 'July',0
          db 'August',0
          db 'September',0
          db 'October',0
          db 'November',0
          db 'December',0
          db 0              ; mark end of menu strings

.code
; program fragment assumes DS:@data
        .
        .
     lea  si,string1
     mov  bx,1
     xor  dx,dx
     call pickstr

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PULLDOWN:    pull-down menu system
Source:      pulldown.asm (a$menu.asm, tprint.asm, tprintce.asm, tputchr.asm
                           strlen.asm, wclear.asm, wframe.asm, wsize.asm
                           wsave.asm, getkey.asm, pickstr.asm and others)

Call with:   DS:[SI] pointing to menu labels
             BH = initial main menu choice, BL = initial submenu choice
             assumes DS:@data
             Unused memory must be released (see STARTUP.ASM and ENDPROG)

             If PullDown is called with BL < 0, only the main headings are
             printed initally; the submenus are printed when ENTER is
             pressed, a mouse button is pressed, or when either the down
             arrow key is pressed or a "down" mouse movement is detected.

             If PullDown is called with BL >= 0, it starts in the full main
             headings plus submenus mode.  In this mode, a mouse button
             click or the ENTER key will exit PullDown.  In either mode,
             ESC, ^C or the user-defined quitkey (see MenuOption) causes
             PullDown to return to the calling program.

             If there are too many main headings to fit across the top of the
             screen, the headings are scrolled left or right as required to
             show the selected heading.  Use Left, Right, Home and End keys
             to change selected headings.  Maximum number of headings: 20

             If there are too many submenu choices under a heading to fit
             on the screen, the selections are scrolled up or down as required
             to show the selected item.  Use Up, Down, PgUp, PgDown keys
             to change selection, or press highlighted letter of selection.
             Maximum number of selections per heading: 255

Returns:     BH = main menu choice, BL = submenu choice
             if CF = 1, ^C or Ctrl-Break was pressed
             if CF = 0
                 AX = 13 if ENTER was pressed
                 AX = user-defined quitkey if pressed (see MenuOption)
                 AX = 0 if insufficient DOS memory is available
                 AX = 27 if ESC was pressed
                 AH = 1-7, AL = 0 if mouse button pressed
Uses:        AX, BX
Supports:    text mode; all row/column configurations supported by ASMLIB
             Text subroutines
Example:

see next page

;    this sample menu has 4 main menu headings:
;                          Critters, Things, Food, Trees
;    submenu choices for each main heading follow each main heading
;    Note that each string is terminated with NUL, and that there's an
;    extra NUL between the end of the submenu choices and the next main
;    heading.
;    The entire set of menu choices is terminated with 2 NUL bytes
;
;    PULLDOWN will return to the calling program when either ESCAPE or
;    ENTER is pressed (AX = ASCII code of key pressed).  PULLDOWN returns
;    AX = 0 if insufficient memory is available to save the underlying
;    screen, or AX = 3 if breaktrap was enabled and Ctrl+Break was pressed.
;
;    On return, BH = the main heading and BL = the submenu choice in effect
;    when the key was pressed.  The first main heading is number 0, and
;    the first submenu choice for each main heading is also number 0.

include asm.inc

extrn     pulldown:proc

.stack

.data
menu    db 'Critters',0
        db 'Goats',0,'Chickens',0,'Turkeys',0,'Cows',0,'Snow dogs',0

        db 0                   ; separate Things from Critters
        db 'Things',0
        db 'Computers',0,'Tractors',0,'CPU chips',0,'Barbie dolls',0

        db 0                   ; separate Food from Things
        db 'Food',0
        db 'Hot dogs',0,'Wheat germ',0,'Lasagne',0,'Cheerios',0
        db 'Potatoes',0,'chocolate chip cooKies',0

        db 0                   ; separate Trees from Food
        db 'Trees',0
        db 'giant Sequoia',0,'black Spruce',0,'Willow',0,'live Oak',0
        db 'Acacia',0,'digger Pine',0

        db 2 dup(0)            ; end of menu choices

.code
; program fragment assumes DS:@data
        .
        .
        .
        lea   si,menu          ; point to menu labels
        xor   bx,bx            ; initial selection is "goats"
        call  pulldown


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SINO:        Spanish language version of YesNo
             waits for 'S' or 'N' key to be pressed
Source:      sino.asm

Call with:   no parameters
             Key pressed may be upper or lower case.  Upper case is
             returned.  Uses BIOS functions
Returns:     AX = 'S' or AX = 'N'
             future version will also return ^C
Uses:        AX
Example:     call  sino


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TEDIT:       ASCIIZ string editor for text modes
             See also GEdit for graphics modes, A$EDIT for general information.
             TEdit turns the cursor off (with CursorOFF) on exit.
Source:      tedit.asm (a$edit.asm, cursor.asm, a$clrw.asm, str2vbuf.asm,
                        crtinfo.asm)

Call with:   DS:[SI] pointing to string buffer; may include a default string
             assumes DS:@data
             CX = byte size of buffer (excluding terminating NUL)
             AH = color attribute
             AL = option bits (see A$EDIT)
             DH = row (offset from top of screen)
             DL = column (offset from left edge of screen)

Returns:     AX = last key pressed (see GetKey for key codes)
             CX = new string length
Uses:        AX, CX, flags
Supports:    text modes; all row/column configurations

Example on next page


; TEdit example:

include asm.inc

extrn   tedit:proc

.data
extrn   estart:word, elast:word
string_buffer   db 120 dup(' ')
len_buffer      equ $-string_buffer
                db 0              ; give it a terminal NUL

.code
; program fragment assumes DS:@data
        .
        .
        .
string_edit:
        lea     si,string_buffer    ; near address of string buffer
        mov     cx,len_buffer       ; byte length of buffer for the string
        mov     dh,row
        mov     dl,column
        mov     ah,attr             ; color attribute
        mov     al,2                ; force lower case
        or      al,4                ; trap Up & Down arrow keys
        call    tedit
        shr     ah,1                ; returned due to extended key?
        jnc     normal_exit

; check for desired extended keys
        cmp     al,72               ; Up arrow key?
        je      go_up
        cmp     al,80               ; Down arrow key?
        je      go_down

; extended key pressed was not Up or Down
; get cursor position when key was pressed & force TEdit to resume
; at that point
        mov     ax,elast            ; last cursor position
        mov     estart,ax           ; force non-zero starting offset
        jmp     string_edit



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TMOUSELIMIT: limits mouse's range of motion on text mode screen
Source:      tmlimit.asm

Call with:   DS:[BX] pointing to character coordinates of minimum and maximum
             rows and columns.  Columns are the horizontal dimension and
             rows are the vertical dimension.
Returns:     nothing
Uses:        nothing
Example:

.data

x0    dw 3          ; first row
y0    dw 1          ; first column
x1    dw 20         ; last row
y1    dw 50         ; last column

.code
; program fragment assumes DS:@DATA
       .
       .
       .
      lea    bx,x          ; DS:[BX] points to limits
      call   tmouselimit

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TMOUSEPOS:   set mouse position on text-mode screen
Source:      tmouspos.asm

Call with:   DH = row (vertical position)
             DL = column (horizontal position)
Returns:     nothing
Uses:        flags
Example:

; I want to center the mouse cursor on a standard 80-column, 25-row screen

include asm.inc

extrn   tmousepos:proc

.code
        .
        .
        .
        mov    dh,12           ; close to vertical center
                               ; coordinates are 0 through 24 vertially
        mov    dl,39           ; coordinates are 0 through 79 horizontally
        call   tmousepos


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TMOUSESTATUS:determine mouse position on text screen & buttons pressed
Source:      tmstatus.asm

Call with:   no parameters
             assumes mouse is installed (see IsMouse in SYSTEM.DOC)
Returns:     if ZF = 1, no buttons are pressed
             if ZF = 0, BX = button code
              BX bit 0 if set = left button is down
              BX bit 1 if set = right button is down
              BX bit 2 if set = center button is down
             DH = row (vertical position)
             DL = column (horizontal position)
Uses:        BX, DX, flags
Example:     call  tmousestatus
             jz    no_buttons     ; no buttons pressed if ZF = 1



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TOLOWER:     converts keycode returned by getkey to lower case
Source:      tolower.asm

Call with:   AX = keycode
Returns:     AX = lower case keycode
             ToLower leaves the keycode alone if the keycode is not
             upper case A-Z.
Uses:        AX
Example:     call   getkey
             call   tolower


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TOUPPER:     converts keycode returned by getkey to upper case
Source:      toupper.asm

Call with:   AX = keycode
Returns:     AX = upper case keycode
             ToUpper leaves the keycode alone if the keycode is not
             lower case a-z.
Uses:        AX
Example:     call   getkey
             call   toupper


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YESNO:       waits for 'Y' or 'N' key to be pressed
Source:      yesno.asm

Call with:   no parameters
             Key pressed may be upper or lower case.  Upper case is
             returned.  Uses BIOS functions
Returns:     AX = 'Y' or AX = 'N'
             future version will also return ^C
Uses:        AX
Example:     call  yesno