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Assembly Source File | 1986-12-12 | 19.3 KB | 672 lines

PAGE 60,132 TITLE Routines to do direct screen I/O ; 011 12-Dec-86 direct.asm ; Copyright (c) 1986 by Blue Sky Software. All rights reserved. _TEXT SEGMENT BYTE PUBLIC 'CODE' _TEXT ENDS CONST SEGMENT WORD PUBLIC 'CONST' CONST ENDS _BSS SEGMENT WORD PUBLIC 'BSS' _BSS ENDS _DATA SEGMENT WORD PUBLIC 'DATA' _DATA ENDS DGROUP GROUP CONST, _BSS, _DATA ASSUME CS: _TEXT, DS: DGROUP, SS: DGROUP, ES: DGROUP _DATA SEGMENT EXTRN _screen:DWORD EXTRN _cursor:DWORD EXTRN _vid_attrib:BYTE EXTRN _vid_snow:BYTE boxloc dw 0 ; stores the starting offset to the dialog box _DATA ENDS _TEXT SEGMENT ;****************************************************************************** ; ; gotorc(r,c) move 'cursor' to specified row, col ; ;****************************************************************************** PUBLIC _gotorc _gotorc PROC NEAR push bp mov bp,sp mov ax,[bp+4] ; row to ax mov cl,5 shl ax,cl ; row * 32 mov bx,ax shl ax,1 shl ax,1 ; row * 128 add ax,bx ; row * 160 mov bx,[bp+6] ; col to bx shl bx,1 ; col * 2 add ax,bx ; row * 160 + col * 2 = cursor mov WORD PTR _cursor,ax mov sp,bp pop bp ret _gotorc ENDP ;****************************************************************************** ; ; disp_str(s) display a string at current location ; ;****************************************************************************** PUBLIC _disp_str _disp_str PROC NEAR push bp mov bp,sp push di push si mov si,[bp+4] mov ah,_vid_attrib ; attribute byte to ah les di,DWORD PTR _cursor ; cursor ptr to es:di jmp SHORT tst_ch ; skip to load/test code chloop: IFDEF nosnow ; if adapter doesn't snow, its quick stosw ; store char and attrib to es:[di++] ELSE ; well, its not so quick or easy.... mov cx,1 call stvideo ENDIF tst_ch: lodsb ; string char to al or al,al ; done when char = 0 jne chloop mov WORD PTR _cursor,di ; update cursor offset pop si pop di mov sp,bp pop bp ret _disp_str ENDP ;****************************************************************************** ; ; disp_char(ch) display a single char at current location ; ;****************************************************************************** PUBLIC _disp_char _disp_char PROC NEAR push bp mov bp,sp push di les di,DWORD PTR _cursor ; cursor loc to es:di mov al,[bp+4] ; get char to store in video memory mov ah,_vid_attrib ; get video attribute IFDEF nosnow stosw ; store 'em and update di ELSE mov cx,1 call stvideo ENDIF mov WORD PTR _cursor,di ; update cursor offset pop di mov sp,bp pop bp ret _disp_char ENDP ;****************************************************************************** ; ; disp_rep(ch,cnt) display a single char cnt times at current location ; ;****************************************************************************** PUBLIC _disp_rep _disp_rep PROC NEAR push bp mov bp,sp push di les di,DWORD PTR _cursor ; cursor loc to es:di mov al,[bp+4] ; get char to store in video memory mov ah,_vid_attrib ; get video attribute mov cx,[bp+6] ; rep count to cx IFDEF nosnow rep stosw ; store 'em and update di ELSE call stvideo ENDIF mov WORD PTR _cursor,di ; update cursor offset pop di mov sp,bp pop bp ret _disp_rep ENDP ;****************************************************************************** ; ; insert_line(r,n) insert a line at row, effects n lines ; ;****************************************************************************** PUBLIC _insert_line _insert_line PROC NEAR push bp mov bp,sp push di push si mov bx,[bp+4] ; ( r + n - 1) * 160 - 2 = add bx,[bp+6] ; end of new last row dec bx mov ax,160 imul bx dec ax dec ax mov si,ax ; (but its the source for the move) add ax,160 ; call addr of dest (where new last mov di,ax ; line will go) std ; to insert a row, need to go backwards call scroll_video ; scroll the video buffer mov al,20h ; fill the inserted line with blanks mov ah,_vid_attrib mov cx,80 IFDEF nosnow rep stosw ELSE call stvideo ENDIF cld ; C expects it this way pop si pop di mov sp,bp pop bp ret _insert_line ENDP ;****************************************************************************** ; ; delete_line(r,n) delete a line at row, effects n lines ; ;****************************************************************************** PUBLIC _delete_line _delete_line PROC NEAR push bp mov bp,sp push di push si mov ax,160 ; get row imul WORD PTR [bp+4] ; turn into offset in video ram mov di,ax add ax,160 ; calc offset of next row mov si,ax call scroll_video ; scroll the video buffer mov al,20h ; fill the last line with blanks mov ah,_vid_attrib mov cx,80 IFDEF nosnow rep stosw ELSE call stvideo ENDIF pop si pop di mov sp,bp pop bp ret _delete_line ENDP ;***************************************************************************** ; ; scroll_video support routine for insert/delete line ; ;***************************************************************************** scroll_video PROC NEAR mov ax,80 ; get # rows to move and imul WORD PTR [bp+6] ; turn into # words to move mov cx,ax IFNDEF nosnow mov al,_vid_snow ; movideo needs vid_snow - get it ENDIF ; before ds gets changed push ds ; save current ds mov bx,WORD PTR _screen+2 ; segment address of video ram mov ds,bx ; moving to/from video ram mov es,bx IFDEF nosnow rep movsw ; scroll the data in the video buffer ELSE call movideo ENDIF pop ds ; restore ds ret scroll_video ENDP ;****************************************************************************** ; ; scrcpy(to,from) ; char far *to, far *from; ; ; copy screen image from to ; ;****************************************************************************** PUBLIC _scrcpy _scrcpy PROC NEAR push bp mov bp,sp push di push si push ds IFNDEF nosnow mov al,_vid_snow ; flag for movideo ENDIF les di,[bp+4] ; es:di is to address lds si,[bp+8] ; ds:si is from address mov cx,80*25 ; HARDCODED screen size in words IFDEF nosnow ; move the screen image rep movsw ELSE call movideo ENDIF pop ds pop si pop di mov sp,bp pop bp ret _scrcpy ENDP ;****************************************************************************** ; ; popup(row,col,nrows,ncols,savp) ; ; pop up a dialog box on the screen starting at row,col. ; If savp is not NULL, the current contents of the video ram ; under the box are saved. ; ;****************************************************************************** PUBLIC _popup _popup PROC NEAR push bp mov bp,sp push di push si mov ax,160 ; calc offset to start of imul WORD PTR [bp+4] ; dialog box - mov cx,[bp+6] ; row * 160 + (col << 1) shl cx,1 add ax,cx mov si,ax ; si now -> box start offset mov boxloc,si ; save it for later mov di,[bp+12] ; get savp, the save addr ptr or di,di ; does user want contents saved? je skipsave mov dx,si ; save current row offset mov bh, BYTE PTR [bp+8] ; nrows to bh mov bl, BYTE PTR [bp+10] ; ncols to bl mov ax,ds ; set es and ds so str instrs mov es,ax ; work the way we want mov cx,WORD PTR _screen+2 ; ds points to video ram mov ds, cx IFNDEF nosnow mov al,es: _vid_snow ; movideo needs _vid_snow push ax ENDIF nxtrow: mov cl,bl ; move ncols to cx xor ch,ch IFDEF nosnow rep movsw ; move data ELSE pop ax ; get/save _vid_snow push ax call movideo ENDIF add dx,160 ; calc offset of next row mov si,dx dec bh ; one more row done, any more? jnz nxtrow IFNDEF nosnow pop ax ; clear stack ENDIF mov ax,es ; restore the ds reg mov ds,ax mov si,boxloc ; reget box starting offset skipsave: mov di,si ; video ram is now the dest mov es,WORD PTR _screen+2 ; video ram segment mov al,201 ; disp the upper left corner mov ah,_vid_attrib ; the video attrib to use IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF mov cx,[bp+10] ; now do the horizontal line dec cx ; its ncols - 2 long dec cx mov [bp+10],cx ; ncols - 2 is used again mov al,205 ; horizontal bar char IFDEF nosnow rep stosw ELSE call stvideo ENDIF mov al,187 ; disp the upper right corner IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF ; now do the blank lines in the body of the box mov bx,[bp+8] ; the body is nrows - 2 long dec bx dec bx add si,160 ; bump row offset mov di,si rownxt: mov al,186 ; do the left vertical bar IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF mov cx,[bp+10] ; now all the blanks mov al,32 IFDEF nosnow rep stosw ELSE call stvideo ENDIF mov al,186 ; do the right vertical bar IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF add si,160 ; bump row offset mov di,si dec bx ; another row done jnz rownxt ; now do the bottom row of the box mov al,200 ; disp the lower left corner IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF mov cx,[bp+10] ; now do the horizontal line mov al,205 ; horizontal bar char IFDEF nosnow rep stosw ELSE call stvideo ENDIF mov al,188 ; disp the lower right corner IFDEF nosnow stosw ; store in video ram ELSE mov cx,1 call stvideo ENDIF pop si ; done, exit pop di mov sp,bp pop bp ret _popup ENDP ;****************************************************************************** ; ; popdwn(row,col,nrows,ncols,savp) ; ; Remove a pop up dialog box from the screen by restoring the prior ; contents from savp. ; ;****************************************************************************** PUBLIC _popdwn _popdwn PROC NEAR push bp mov bp,sp push di push si mov ax,160 ; calc offset to start of imul WORD PTR [bp+4] ; dialog box - mov cx,[bp+6] ; row * 160 + (col << 1) shl cx,1 add ax,cx mov di,ax ; di now -> box start offset mov si,[bp+12] ; get savp, the save addr ptr mov dx,di ; save current row offset mov bh, BYTE PTR [bp+8] ; nrows to bh mov bl, BYTE PTR [bp+10] ; ncols to bl mov es,WORD PTR _screen+2 ; oh yea, es points to video ram next: mov cl,bl ; move ncols to cx xor ch,ch IFDEF nosnow rep movsw ; move data ELSE mov al,_vid_snow call movideo ENDIF add dx,160 ; calc offset of next row mov di,dx dec bh ; one more row done, any more? jnz next pop si pop di mov sp,bp pop bp ret _popdwn ENDP IFNDEF nosnow ;****************************************************************************** ; ; movideo - move data to/from video memory ; - current video mode must be passed in al ; ;****************************************************************************** movideo PROC NEAR test al,1 ; do we need to check for snow? jnz goslow rep movsw ; no snow, full speed ahead ret ; that's all there is to it goslow: push dx ; it's a cga, go slow time mov dx,03dah ; dx = cga status port address wait1: in al,dx ; get retrace status test al,8 ; vertical retrace? jnz mov_it ; yes, go get the char ror al,1 ; low bit set? (horizontal retrace) jc wait1 ; current retrace may be almost done cli ; no interrupts until char loaded wait2: in al,dx ; wait for start of next retrace ror al,1 jnc wait2 mov_it: movsw ; move word to/from video ram sti ; allow interrupts loop wait1 ; all chars transfered? pop dx ; restore dx ret movideo ENDP ;****************************************************************************** ; ; stvideo - store the word in ax to video ram cx times ; ;****************************************************************************** stvideo PROC NEAR test _vid_snow,1 ; do we need to slow for no snow? jnz slowgo rep stosw ; no snow, full speed ahead ret ; that's all there is to it slowgo: push bx ; snow, go slow push dx mov dx,03dah ; dx = cga status port address mov bx,ax wait3: in al,dx ; get retrace status test al,8 ; vertical retrace? jnz sto_it ; yes, go get the char ror al,1 ; low bit set? (horizontal retrace) jc wait3 ; current retrace may be almost done cli ; no interrupts until char loaded wait4: in al,dx ; wait for start of next retrace ror al,1 jnc wait4 sto_it: mov ax,bx stosw ; store word to video ram sti ; allow interrupts loop wait3 ; all chars transfered? pop dx ; restore dx & bx pop bx ret stvideo ENDP ENDIF _TEXT ENDS END