Simtel MSDOS 1992 June

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/ Simtel MSDOS 1992 June / SIMTEL_0692.cdr / msdos / sysutl / safari2.arc / CTYPE.ASM next >

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Assembly Source File | 1987-08-21 | 22.3 KB | 564 lines

;CTYPE.COM for the IBM Personal Computer - 1987 by Jeff Prosise bios_data segment at 40h org 60h cursor_mode dw ? ;cursor scan lines org 63h addr_6845 dw ? ;CRT Controller base address org 87h ega_info db ? ;EGA info byte bios_data ends ;---------------------------------------------------------------------- code segment para public 'code' assume cs:code,ds:code org 100h begin: jmp ctype program db 'CTYPE 1.0 ' copyright db '(c) 1987 Ziff Communications Co.',1Ah author db 'Jeff Prosise' header db 'PC Magazine Cursor Definition Utility',0 subheader db 'CTYPE /',0 footer1 db '< Use arrow keys to navigate grid >',0,0 db 'ENTER : Select cursor and exit',0 db 'SPACEBAR : View cursor with text',0 footer2 db '< Press SPACEBAR to return >',0,0 db 'A single line of sample text',0 errmsg db 13,10,'Illegal parameters',13,10,'$' adapter db 3 ;0=MDA, 1=CGA, 2=EGA, 3=VGA points label byte lpoints dw 8 ;scan lines per row (default=CGA) rows db 24 ;number of rows (default=CGA, MDA) columns db ? ;number of video columns attr1 db 02h ;main video attribute attr2 db 1Fh ;auxiliary video attribute old_attr db 0 deltacol db 2 ;space between frame columns startcol db ? ;first frame column vpage db ? ;active video page textrow db ? ;row where text footer begins ;----------------------------------------------------------------------------- ;CTYPE is the main procedure. ;----------------------------------------------------------------------------- ctype proc near ; ;Find the current color of the screen for clearing later. ; mov ah,15 ;get columns and page int 10h mov columns,ah ;save them mov vpage,bh mov ah,8 ;save old screen colors int 10h mov old_attr,ah mov ax,bios_data ;point ES to BIOS data area mov es,ax assume es:bios_data ; ;Determine what type of video adapter is active, whether video is color ;or monochrome, and how many scan lines make up each character box. ; mov ax,1A00h ;check for a VGA int 10h cmp al,1Ah ;is AL set to 1Ah? jne check_ega ;no, then no VGA present cmp bl,7 ;test for active VGA jb check_ega cmp bl,8 ja check_ega call SetVideoParms ;determine rows and points cmp bl,7 ;reset attributes if monochrome je mono jmp short checkparm ;done if video is color check_ega: dec adapter ;assume this is an EGA mov ah,12h ;video function 12h mov bl,10h ;subfunction - return EGA info int 10h cmp bl,10h ;did BL return unchanged? je no_ega ;yes, then no EGA test ega_info,8 ;is the EGA currently active? jnz no_ega ;no, then continue the check call SetVideoParms ;determine rows and points or bh,bh ;is BH zero? jne mono ;no, then it's a mono system jmp short checkparm ;yes, then it's color no_ega: dec adapter ;assume this is a CGA test addr_6845,40h ;is bit 6 of the CRTC address set? jnz checkparm ;yes, then it's a CGA mov points,14 ;no, then it's an MDA dec adapter ;set ADAPTER to zero for MDA mono: mov attr1,07h ;alter video parameters for mono mov attr2,70h ; ;Check the command line for cursor definition parameters. ; checkparm: push cs ;point ES to code segment pop es assume es:code cld ;clear DF mov di,82h ;point ES:DI to text of line cmp byte ptr [di-2],2 ;at least 2 characters entered? jb noparm ;no, then nothing was entered mov cx,10 ;check for slash character mov al,'/' repne scasb jcxz noparm ;branch if command line is empty mov cx,[di] ;get 2 characters after slash and cx,0DFDFh ;capitalize them sub cx,4141h ;then normalize them cmp ch,points ;see if they're in range jae parm_error cmp cl,points jae parm_error ; ;Set the cursor and exit. ; xchg ch,cl ;swap CH and CL mov al,points ;calculate ending scan line sub al,cl dec al cmp ch,al ;make sure parameters are legal ja parm_error mov cl,al ;transfer scan line to CL call SetCursorMode ;set cursor shape cursor_exit: mov ax,4C00h ;exit with ERRORLEVEL = 0 int 21h ; ;Command line parameters are out of range. Print error message and exit. ; parm_error: mov ah,9 ;print error message mov dx,offset errmsg int 21h mov ax,4C01h ;exit with ERRORLEVEL = 1 int 21h ; ;Create the cursor definition screen for interactive mode selection. ; noparm: ; mov ah,15 ;get columns and page ; int 10h ; mov columns,ah ;save them ; mov vpage,bh cmp columns,80 ;at least 80 columns displayed? jae col80 ;yes, then branch mov deltacol,1 ;no, then adjust for short display col80: call ClearScreen ;clear the screen mov ah,1 ;hide the cursor mov ch,20h int 10h mov ax,0920h ;blank the screen header line mov bl,attr2 mov bh,vpage mov cl,columns xor ch,ch int 10h mov si,offset header ;display screen header xor dh,dh mov dl,columns sub dl,37 shr dl,1 call WriteString call DrawFrame ;draw the cursor selection frame mov ah,2 ;display 'CTYPE /XX' subheader mov dh,2 mov dl,startcol mov bl,attr1 mov si,offset subheader call WriteString ; ;Position and display a 2-line underline cursor. ; mov cl,points ;get number of scan lines dec cl ;decrement it for ending line mov ch,cl ;set starting line one higher dec ch jmp short display ; ;Enter a loop, polling the keyboard for keypresses. ; getkey: mov ah,0 ;get a keypress int 16h or al,al ;extended code? je excode ;yes, then branch cmp al,32 ;SPACEBAR? jne nospace call ShowText ;show cursor with text jmp short getkey ;return for more nospace: cmp al,13 ;ENTER key? jne getkey ;no, then ignore keypress call ClearScreen ;clear screen and exit jmp cursor_exit excode: cmp ah,72 ;Up-arrow? jne checklft or ch,ch ;decrement starting scan line jne ex1 mov ch,cl jmp short display ex1: dec ch jmp short display checklft: cmp ah,75 ;Left-arrow? jne checkrt inc cl ;increment ending scan line cmp cl,points jne display mov cl,ch jmp short display checkrt: cmp ah,77 ;Right-arrow? jne checkdn cmp ch,cl ;decrement ending scan line jne rt1 mov cl,points dec cl jmp short display rt1: dec cl jmp short display checkdn: cmp ah,80 ;Down-arrow? jne getkey ;no, then ignore the keypress cmp ch,cl ;increment starting scan line jne dn1 xor ch,ch jmp short display dn1: inc ch display: call ShowParm ;display command line parameters call LocateCursor ;reposition the cursor call SetCursorMode ;then display it in its new form jmp short getkey ;return to keyboard loop ctype endp ;----------------------------------------------------------------------------- ;SetVideoParms retrieves and stores the number of rows displayed and the ;number of scan lines per character. ;----------------------------------------------------------------------------- SetVideoParms proc near push bx ;save BX mov ax,1130h ;get scan line and row count int 10h mov rows,dl ;save them (rows - 1) mov points,cl pop bx ;restore BX ret SetVideoParms endp ;----------------------------------------------------------------------------- ;SetCursorMode sets the shape of the cursor. ;Entry: CH,CL - beginning and ending scan lines ;----------------------------------------------------------------------------- SetCursorMode proc near push cx ;save CX for screen location cmp adapter,2 ;is an EGA active? jne scm1 ;no, then branch inc cl ;yes, then adjust ending line cmp cl,points ;wrap around if necessary jne scm0 xor cl,cl scm0: cmp ch,cl ;should this be a block cursor? jne scm1 ;no, then branch mov cl,1Eh ;yes, then adjust ending scan line scm1: push es ;save ES mov ax,bios_data mov es,ax assume es:bios_data mov dx,addr_6845 ;get CRT Controller address mov cursor_mode,cx ;save definition in BIOS area pop es ;restore ES assume es:code mov al,10 ;OUT CH and CL to cursor registers out dx,al inc dx mov al,ch out dx,al dec dx mov al,11 out dx,al inc dx mov al,cl out dx,al pop cx ;retrieve nominal cursor shape ret SetCursorMode endp ;----------------------------------------------------------------------------- ;ShowText displays the current cursor on a line of text. ;----------------------------------------------------------------------------- endcol db ? ;ending column ShowText proc near push cx ;save cursor parameter call ClearRegion ;clear lower part of screen mov si,offset footer2 ;display new footer mov cx,3 call DrawFooter mov ah,2 ;home the cursor dec dh int 10h mov endcol,dl ;calculate rightmost column add endcol,27 input: mov ah,0 ;get a keystroke int 16h or al,al ;extended code? je fkey ;yes, then branch cmp al,32 ;SPACEBAR? jne input ;no, then ignore it call ClearRegion ;restore main footer mov si,offset footer1 mov cx,4 call DrawFooter pop cx ;restore cursor parameter call LocateCursor ;restore cursor position ret fkey: cmp ah,75 ;Left-arrow? jne fkey1 cmp dl,startcol ;at left end of line? je input ;yes, then don't move dec dl ;move one character left fkey0: mov ah,2 mov bh,vpage int 10h jmp short input ;return for more fkey1: cmp ah,77 ;Right-arrow? jne input ;no, then ignore it cmp dl,endcol ;at right end of line? je input ;yes, then don't move inc dl ;advance cursor jmp short fkey0 ShowText endp ;----------------------------------------------------------------------------- ;LocateCursor positions the cursor inside the selection frame. ;Entry: CH,CL - starting and ending cursor scan lines ;----------------------------------------------------------------------------- LocateCursor proc near mov dh,ch ;calculate screen row from CH add dh,4 mov dl,startcol ;calculate column from CL add dl,2 mov al,deltacol add dl,al inc al mov bl,points sub bl,cl dec bl mul bl add dl,al mov bh,vpage ;set video page number mov ah,2 ;position cursor int 10h ret LocateCursor endp ;----------------------------------------------------------------------------- ;ShowParm updates the display of the current cursor's /XX parameters. ;Entry: CH,CL - starting and ending scan lines ;----------------------------------------------------------------------------- ShowParm proc near mov ah,2 ;position the cursor mov bh,vpage mov dh,2 mov dl,startcol add dl,7 int 10h mov ah,0Eh ;write first character mov al,ch add al,41h int 10h mov ah,0Eh ;write second character mov al,points sub al,cl add al,40h int 10h ret ShowParm endp ;----------------------------------------------------------------------------- ;DrawFrame draws the cursor definition frame. ;----------------------------------------------------------------------------- numpoints dw ? ;counter for dots per line ; DrawFrame proc near mov al,points ;calculate length of top line mov bl,deltacol inc bl mul bl add ax,3 mov cx,ax ;transfer result to CX mov bl,columns ;calculate starting column number sub bl,al shr bl,1 mov startcol,bl mov ah,2 ;position cursor for top line mov dh,3 mov dl,startcol mov bh,vpage int 10h mov ax,0920h ;blank out the top line mov bl,attr2 int 10h mov cx,lpoints ;fill in text of top line mov dh,3 mov dl,startcol add dl,deltacol add dl,2 mov al,'A' drawloop1: mov bl,al mov ah,2 int 10h mov ah,0Eh mov al,bl int 10h add dl,deltacol inc dl mov al,bl inc al loop drawloop1 mov cx,lpoints ;then blank the vertical leg mov dh,4 mov dl,startcol mov bl,attr2 drawloop2: push cx mov ah,2 int 10h mov ax,0920h mov cl,deltacol inc cl xor ch,ch int 10h inc dh pop cx loop drawloop2 mov cx,lpoints ;fill in the dots and text mov numpoints,cx mov dh,4 mov dl,startcol inc dl mov al,'A' drawloop3: push cx mov bl,al mov ah,2 int 10h mov al,bl mov ah,0Eh int 10h mov cx,numpoints ;fill one grid line drawloop4: mov ah,2 add dl,deltacol inc dl int 10h mov ax,0EF9h int 10h loop drawloop4 dec numpoints ;one less dot on next line mov al,bl inc al inc dh mov dl,startcol inc dl pop cx loop drawloop3 mov textrow,dh ;store current row number inc textrow mov si,offset footer1 ;draw text footer mov cx,4 call DrawFooter ret DrawFrame endp ;----------------------------------------------------------------------------- ;DrawFooter writes a block of text below the selection frame. ;Entry: CX - number of lines ;----------------------------------------------------------------------------- DrawFooter proc near mov dh,textrow ;initialize cursor position mov dl,startcol mov bl,attr1 ;set attribute drawloop5: push cx ;enter loop call WriteString ;write one line inc dh ;advance cursor mov dl,startcol pop cx loop drawloop5 ;loop until done ret DrawFooter endp ;----------------------------------------------------------------------------- ;WriteString writes an ASCIIZ text string to video memory. ;Entry: DS:SI - string address ; DH,DL - starting cursor address ; BL - attribute ;----------------------------------------------------------------------------- WriteString proc near mov ah,2 ;position cursor mov bh,vpage int 10h lodsb ;get a byte or al,al ;is it the delimiter? je ws1 ;yes, then exit mov ah,9 ;no, then display it mov cx,1 int 10h inc dl ;advance the cursor jmp short WriteString ;loop until done ws1: ret WriteString endp ;----------------------------------------------------------------------------- ;ClearScreen clears the display and homes the cursor. ;----------------------------------------------------------------------------- ClearScreen proc near mov ah,2 ;home the cursor xor dx,dx mov bh,vpage int 10h xor cx,cx ;define upper right corner clear1: mov dl,columns ;define lower right corner dec dl mov dh,rows mov bh,old_attr mov ax,0600h ;video function 6 int 10h ;clear region ret ClearScreen endp ;----------------------------------------------------------------------------- ;ClearRegion clears the lower portion of the display. ;----------------------------------------------------------------------------- ClearRegion proc near mov ch,textrow ;define upper left corner xor cl,cl jmp short clear1 ClearRegion endp ; code ends end begin