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Assembly Source File | 1987-09-15 | 44.7 KB | 915 lines

;Copyright 1987, John J. Newlin PUBLIC setxy,upcase,cga_retrace,fillstr,screenwrite,init_screen,savebox PUBLIC restbox,shiftl,shiftr,hi,lo,move,chdir,findfirst,findnext,cls PUBLIC strng,video_mode,set_mem,getdir,msdos,set_dta,scroll,keycode PUBLIC exec,hide_cursor,rest_cursor,save_cursor,longstr,addlong toolcode segment word PUBLIC 'code' assume cs:toolcode ;;;;;;;;;;;;;; ;changes lower case char to upper case ;function upcase(ch : char) : char upcase proc near push bp mov bp,sp ;save BP mov ax,[bp+4] ;get the char cmp al,97 ;is it 'a' or above? jb u_exit ;no, do nothing cmp al,122 ;is it 'z' or below? ja u_exit ;no, do nothing sub al,32 ;change to upper case u_exit: mov [bp+6],ax ;return as function result pop bp ret 2 upcase endp ;;;;;;;;;;;;;;; ;uses undocumented interrupt 2E to execute a program ;procedure exec(var name : string); exec proc near push bp ;save bp mov bp,sp ;bp points to the stack push ax ;save push bx ; all push cx ; other push dx ; regs push di push si jmp past ;jump over storage area mls_ds dw 0 ;stores our DS reg mls_es dw 0 ;stores our ES reg mls_ss dw 0 ;stores our SS reg mls_sp dw 0 ;stores our SP reg mls_bp dw 0 ;stores our BP reg past: mov cs:mls_ss,ss ;save SS reg mov cs:mls_sp,sp ;save SP reg mov cs:mls_es,es ;save ES reg mov cs:mls_ds,ds ;save DS reg mov cs:mls_bp,bp ;save BP reg push ds pop es ;set ES = DS mov si,[bp+4] ;si points to command string int 2Eh ;call DOS to execute mov ax,cs:mls_ss ;retrieve SS reg mov ss,ax ;reset it mov sp,cs:mls_sp ;retrieve SP reg mov ax,cs:mls_ds ;retrieve DS reg mov ds,ax ;reset it mov ax,cs:mls_es ;retrieve ES reg mov es,ax ;reset it mov bp,cs:mls_bp ;retrieve BP reg pop si ;restore pop di ; all pop dx ; other pop cx ; regs pop bx pop ax pop bp ret 2 exec endp ;;;;;;;;;;;; ;returns keyboard status byte, ascii code, and scan code ;function keycode(var status,ascii,scan : integer) : boolean; keycode proc near push bp mov bp,sp ;BP points to stack push bx ;Marshal says save BX push si ;and also SI mov ah,1 ;Int 16h to check buffer int 16h ;call BIOS mov word ptr [bp+10],0 ;function returns a false jz _no_key ;no key avail, so depart mov ah,0 ;key is avail, so get it int 16h ;call BIOS push ax ;save result mov ah,2 ;to get status byte int 16h ;call BIOS mov bx,[bp+8] ;get address of status mov ah,0 ;zero the MSB mov [bx],ax ;set status pop ax ;restore AX mov bx,[bp+6] ;get address of ascii mov si,[bp+4] ;get address of scan xor dx,dx ;zero DX mov dl,ah ;put scan value in DX mov [si],dx ;move it into scan mov dl,al ;move ascii code into DL mov [bx],dx ;and into ascii mov word ptr[bp+10],1 ;function returns true _no_key: pop si pop bx pop bp ret 6 keycode endp ;;;;;;;;;;;;;;; ;scrolls the specified area of the screen up/down number of lines ;normalize to screen dimensions of (1,1) to (25,80) ;procedure scroll(ulx,uly,lrx,lry,lines,attr,dir : integer); external; scroll proc near push bp mov bp,sp ;BP points to stack push bx ;must preserve BX mov bh,byte ptr 6[bp] ;get desired attribute mov ch,byte ptr 14[bp] ;upper left y coord dec ch ;normalize mov cl,byte ptr 16[bp] ;upper left x coord dec cl ;normalize mov dh,byte ptr 10[bp] ;lower right y coord dec dh ;normalize mov dl,byte ptr 12[bp] ;lower right x coord dec dl ;normalize mov al,byte ptr 08[bp] ;no. of lines to scroll cmp byte ptr 4[bp],0 ;scroll up? je scroll_up ;yes mov ah,7 ;no, scroll down jmp short scroll_it ;do it scroll_up: mov ah,6 ;scroll up scroll_it: int 10h ;call BIOS pop bx pop bp ret 14 scroll endp ;;;;;;;;;;;;; ;set the Disk Transfer Area to desired structure ;procedure set_dta(var buffer : buff_type); set_dta proc near push bp mov bp,sp ;BP points to stack mov dx,[bp+4] ;get address of buffer mov ah,1Ah ;function to set DTA int 21h ;DOS will do it pop bp ret 2 set_dta endp ;;;;;;;;;;;;;; ;call DOS interrupt 21h with registers set as desired ;procedure msdos(var regs : regtype) msdos proc near push bp mov bp,sp ;BP points to stack push ax ;save push bx ; all push cx ; regs push dx ; push di ; push si ; push ds ; push es ; jmp short pst ;leap over code seg data saveit dw 0 pst: mov bx,[bp+4] ;BX points to regs structure mov ax,[bx+0] ;set AX mov cx,[bx+4] ;set CX mov dx,[bx+6] ;set DX mov di,[bx+8] ;set DI mov si,[bx+10] ;set SI mov cs:saveit,ds ;save our DS reg push [bx+14] ;push ES value in structure pop es ;pop it into ES push [bx+2] ;push BX value in structure push [bx+12] ;push DS value in structure pop ds ;set DS pop bx ;set BX push bp ;save our BP during call int 21h ;call DOS pop bp ;restore our BP push ds ;save returned DS push bx ;save returned BX mov bx,cs:saveit ;get our DS reg mov ds,bx ;set our DS mov bx,[bp+4] ;get pointer to structure pop [bx+2] ;set structure BX pop [bx+12] ;set structure DS mov [bx+0],ax ;set structure AX mov [bx+4],cx ;set structure CX mov [bx+6],dx ;set structure DX mov [bx+8],di ;set structure DI mov [bx+10],si ;set structure SI push es ;push returned ES pop [bx+14] ;pop it into structure ES pushf ;push returned flags pop [bx+16] ;pop into structure flags pop es ;restore pop ds ; all pop si ; regs pop di ; pop dx ; pop cx ; pop bx ; pop ax ; pop bp ; ret 2 msdos endp ;;;;;;;;;;;;; ;returns active drive and directory in string ;drive code 0 = A, 1 = B, etc. ;procedure getdir(var dirname : string); getdir proc near push bp mov bp,sp ;BP points to stack push si ;must preserve SI mov si,[bp+4] ;SI points to dirname mov ah,19h ;set up to get drive desig int 21h ;call DOS add al,65 ;make it a char mov byte ptr[si],al ;put in string inc si ;point to next char mov al,58 ;58 = ':' mov byte ptr[si],al ;put in string inc si ;point to next char mov byte ptr[si],'\' ;put in backslash inc si ;point to next char mov ah,47h ;set up to get default dir int 21h ;call DOS pop si pop bp ret 2 getdir endp ;;;;;;;;;;;;;; ;set program memory to only what is required by code, data, and stack ;function set_mem : integer; set_mem proc near push bp ;save BP mov bp,sp ;BP points to stack push es ;save ES push bx ;save BX mov ax,ds ;AX = DS mov bx,cs ;BX = CS sub ax,bx ;ds-cs = data seg paragraphs inc ax ;round up one mov bx,ax ;store in BX mov ax,bp ;AX = stack pointer mov cl,4 ;for shifting shr ax,cl ;convert to paragraphs add ax,bx ;add BX add ax,32 ;bump by 32 paragraph overhead mov bx,ax ;store in BX mov cx,ax ;save in CX mov ax,cs ;AX = code segment sub ax,16 ;AX set to mem control block seg mov es,ax ;ES = mem control block seg mov ah,4Ah ;DOS mod alloc mem function int 21h ;DOS will do it jnc no_mem_err ;error will set carry flag mov cx,-1 ;if error return -1 no_mem_err: mov [bp+4],cx ;function result pop bx ;restore BX pop es ;restore ES pop bp ;restore BP ret set_mem endp ;;;;;;;;;;;;;;; ;converts an integer into a Pascal string ;procedure strng(num : integer; var numstr : string) strng proc near push bp mov bp,sp ;BP points to stack push bx ;preserve BX push di ;preserve DI push es ;preserve ES push ds ;preserve DS mov ax,ds ;get DS mov es,ax ;make ES = DS mov di,[bp+4] ;DI points to string mov dx,[bp+6] ;AX = integer to convert xor bx,bx ;zero BX new_char: mov ax,dx xor dx,dx ;zero DX mov cx,10 ;for decimal conversion div cx ;AX gets result xchg ax,dx ;swap AX and DX add al,30h ;convert to ascii push ax ;save AX inc bx ;bump count cmp dx,0 ;are we done? jnz new_char ;no, get another digit str_loop: pop ax ;restore AX stosb ;put in string dec bx ;dec count cmp bx,0 ;are we done? jne str_loop ;no, do again mov al,0 ;AL = 0 stosb ;end of string byte pop ds ;restore pop es ; regs pop di ; pop bx ; pop bp ; ret 4 strng endp ;;;;;;;;;;; ;clears the entire screen using the specified attribute ;procedure cls(attr : integer); cls proc near push bp mov bp,sp ;BP points to stack push bx ;preserve BX mov ah,7 ;code to scroll mov al,0 ;AL = 0 so all will be blanked mov bh,byte ptr[bp+4] ;attribute for scroll mov cx,0 ;CL = 0, CH = 0 mov dx,184Fh ;DL = 79, DH = 24 int 10h ;call BIOS pop bx ;restore BX pop bp ret 2 cls endp ;;;;;;;;;;;;;;;;; ;returns current video mode ;function vide_mode : integer video_mode proc near push bp mov bp,sp ;BP points to stack mov ah,0Fh ;set up to get mode int 10h ;call BIOS mov ah,0 ;clear upper half mov 4[bp],ax ;return function result pop bp ret video_mode endp ;;;;;;;;;;;;;;;;;; ;if file is found, returns a 0 - returns non-zero otherwise ;function findfirst(var pathname : string; attr : integer) : integer findfirst proc near push bp mov bp,sp ;BP points to stack mov dx,[bp+6] ;DX points to ASCIIZ string mov cx,[bp+4] ;CX = file attribute mov ah,4Eh ;set up to find first int 21h ;call DOS jc ff_err ;carry flag set if not found mov ax,0 ;was found, so AX = 0 ff_err: mov [bp+8],ax ;return function result pop bp ret 4 findfirst endp ;;;;;;;;;;;;;;;;;; ;returns 0 if next find is successful, non-zero if not ;function findnext : integer findnext proc near push bp mov bp,sp ;BP points to stack mov ah,4Fh ;set up for find next int 21h ;call DOS jc fn_err ;carry flag set if not found mov ax,0 ;was found, so AX = 0 fn_err: mov [bp+4],ax ;return function result pop bp ret findnext endp ;;;;;;;;;;;;;;;;;;;;;;; ;changes to specified drive/directory ;returns 0 if successful, non-zero if not ;function chdir(var dirname : string) : integer; chdir proc near push bp mov bp,sp ;BP points to stack push si ;must preserve SI mov si,[bp+4] ;SI points to dirname cmp byte ptr [si+1],':' ;is drive spec present jne no_drive ;if not, skip drive stuff mov dl,[si] ;yes, get drive letter cmp dl,65 ;is it below 'A' jb no_drive ;yes, skip cmp dl,90 ;is it above 'Z' ja lo_case_desig ;yes, check lower case sub dl,65 ;convert letter to byte jmp drv_ok ;continue lo_case_desig: cmp dl,97 ;is it below 'a' jb no_drive ;yes, skip cmp dl,122 ;is it above 'z' ja no_drive ;yes, skip sub dl,97 ;convert letter to byte drv_ok: mov ah,0Eh ;change drive int 21h ;call DOS cmp byte ptr [si+2],0 ;are we done? je are_done ;yes no_drive: mov dx,si ;dx points to directory mov ah,3Bh ;set up to change int 21h ;call DOS jc ch_err ;if err don't zero AX are_done: mov ax,0 ;AX = 0 ch_err: mov [bp+6],ax ;return function result pop si ;restore SI pop bp ret 2 chdir endp ;;;;;;;;;;;;;;; ;returns most significant byte of num ;function hi(num : integer) : integer; hi proc near push bp mov bp,sp ;BP points to stack mov ax,[bp+4] ;AX = num xchg ah,al ;swap mov ah,0 ;clear upper half mov [bp+6],ax ;return function result pop bp ret 2 hi endp ;;;;;;;;;;;;;;;;; ;returns least significant byte of num ;functio lo(num : integer) : integer; lo proc near push bp mov bp,sp ;BP points to stack mov ax,[bp+4] ;AX = num mov ah,0 ;clear upper half mov [bp+6],ax ;return function result pop bp ret 2 lo endp ;;;;;;;;;;;;;;;;; ;shifts target to the left by quantity bits ;function shiftl(target,bits : integer) : integer; shiftl proc near push bp mov bp,sp ;BP points to stack mov cl,byte ptr [bp+4] ;CL = bits mov ax,[bp+6] ;AX = target shl ax,cl ;shift left mov [bp+8],ax ;return function result pop bp ret 4 shiftl endp ;;;;;;;;;;;;;;;;; ;shifts target to the right by quantity bits ;function shiftr(target,bits : integer) : integer; shiftr proc near push bp mov bp,sp ;BP points to stack mov cl,byte ptr [bp+4] ;CL = bits mov ax,[bp+6] ;AX = target shr ax,cl ;shift right mov [bp+8],ax ;return function result pop bp ret 4 shiftr endp ;;;;;;;;;;;;;;;;;; ;initializes video ram address and video type variables ;procedure init_screen; init_screen proc near push bp jmp short past_data vid_addr dw 0B000h mono_box db 1 past_data: push ds ;save DS push bx ;save BX mov ah,0Fh ;set up to get mode int 10h ;call BIOS cmp al,7 ;is it mono? je mc ;yes mov ax,0B800h ;no, set up for CGA mov cl,0 ;for mono_box jmp short continue ;and continue mc: mov ax,0B000h ;set up for mono mov cl,1 ;for mono_box continue: mov cs:vid_addr,ax ;save video address mov cs:mono_box,cl ;save the flag pop bx ;restore BX pop ds ;restore DS pop bp ret init_screen endp ;;;;;;;;;;;;;;;;;;; ;waits for horiz and vertical retrace before writing to video ram cga_retrace proc near retrace: in al,dx ;get status test al,8 ;check retrace jnz horiz ;ok - chech horiz rcr al,1 ;check retrace jc retrace ;check again horiz: in al,dx ;get status rcr al,1 ;check retrace jnc horiz ;test again store_it: ret cga_retrace endp ;;;;;;;;;;;;;;;;;; ;saves the video area defined by row,col, width and depth to buff ;procedure savebox(col,row,width,depth,buff); savebox proc near push bp mov bp,sp ;BP points to stack push ds ;save push es ; important push bx ; regs push di ; on push si ; stack push ss pop es ;ES = SS jmp short mc2 ;jump over data and proc s_width dw 0 s_offset dw 0 mc2: mov ax,cs:vid_addr ;get video address continue2: mov ds,ax ;put in DS mov di,[bp+4] ;DI points to buffer mov ax,[bp+10] ;AX = row dec ax ;normalize mov bx,160 ;160 bytes per row mul bx ;times number of rows mov si,ax ;SI points to video start mov bx,[bp+12] ;BX = col dec bx ;normalize shl bx,1 ;times 2 mov dx,[bp+8] ;DX = width shl dx,1 ;times 2 mov cs:s_width,dx ;save width mov cs:s_offset,160 ;save offset sub cs:s_offset,dx ;subtract width add si,bx ;add to SI mov cx,[bp+6] ;CX = depth cmp cs:vid_addr,0B000h ;mono screen? mov ax,8[bp] ;AX = width je mono9 ;yes, go to mono routine again9: push cx ;save CX = depth mov cx,[bp+8] ;CX = width mov dx,03DAh ;CGA port loop9: cli ;halt interrupts call cga_retrace ;wait for CGA retrace store9: movsw ;store the char and attribute sti ;restore interrupts loop loop9 ;do again pop cx ;restore CX = depth add si,cs:s_offset ;add the offset loop again9 ;and continue jmp y_done ;until done mono9: push cx ;save CX = depth mov cx,ax ;CX = AX = width rep movsw ;do it add si,cs:s_offset ;add the offset pop cx ;restore CX = depth loop mono9 ;do again y_done: pop si ;restore pop di ; regs pop bx ; from pop es ; the pop ds ; stack pop bp ret 10 savebox endp ;;;;;;;;;;;;;;;;;;;; ;restores buffer to video area defined by col, row, width, and depth ;procedure restbox(col,row,width,depth,buff : integer) restbox proc near push bp mov bp,sp ;BP points to stack push ds ;save push es ; important push bx ; regs push di ; on push si ; stack mov ax,cs:vid_addr ;AX = video address mov es,ax ;ES = video address mov si,[bp+4] ;SI points to buff mov ax,[bp+10] ;AX = row dec ax ;normalize mov bx,160 ;160 bytes per row mul bx ;times number of rows mov di,ax ;DI points to area mov bx,[bp+12] ;BX = col dec bx ;normalize shl bx,1 ;times 2 mov dx,[bp+8] ;DX = width shl dx,1 ;times 2 mov cs:s_width,dx ;store width mov cs:s_offset,160 ;store offset sub cs:s_offset,dx ;DX = offset add di,bx ;DI points to area mov cx,[bp+6] ;CX = depth cmp cs:mono_box,1 ;mono screen? mov ax,[bp+8] ;AX = video segment je mono6 ;go to mono routine again6: push cx ;save CX = depth mov cx,[bp+8] ;CX = width mov dx,03DAh ;CGA port address loop6: cli ;turn off interrupts call cga_retrace ;wait for retrace store6: movsw ;store char and attribute sti ;interrupts enabled loop loop6 ;do again pop cx ;CX = depth add di,cs:s_offset ;add offset to DI loop again6 ;and do another row jmp x_done ;done with CGA mono6: push cx ;save CX = depth mov cx,ax ;CX = width rep movsw ;move all at once add di,cs:s_offset ;add offset to DI pop cx ;CX = depth loop mono6 ;do another row x_done: pop si ;restore pop di ; regs pop bx ; from pop es ; the pop ds ; stack pop bp ret 10 restbox endp ;;;;;;;;;;;;;;;;;;;;;;; ;writes a string directly to video ram ; procedure screenwrite(col,row,attr:integer; var str : string); screenwrite proc near push bp mov bp,sp ;BP points to stack push es ;save push bx ; regs push di ; on push si ; stack mov ax,[bp+8] ;AX = row dec ax ;normalize mov bx,160 ;160 bytes per row mul bx ;AX = AX * 160 mov di,ax ;DI points to video area mov bx,[bp+10] ;BX = col dec bx ;normalize shl bx,1 ;adjust for attr byte add di,bx ;DI = DI + col mov si,[bp+4] ;SI points to string mov ah,[bp+6] ;AH = attribute mov dx,cs:vid_addr ;DX = video segment cmp byte ptr cs:mono_box,1 ;mono screen? mov es,dx ;ES = video segment je sw_mono ;yes, go to mono routine mov dx,03dah ;CGA port address sw_getnext: lodsb ;AL = char cmp al,0 ;end of string? je sw_exit ;yes, exit mov cx,ax ;no, save AX in CX cli ;disable interrupts call cga_retrace ;wait for retrace sw_store: mov ax,cx ;restore AX stosw ;store word in video ram sti ;enable interrupts jmp sw_getnext ;get next character sw_mono: lodsb ;AL = next char cmp al,0 ;end of string? je sw_exit ;yes, exit stosw ;no, store in video ram jmp sw_mono ;get next character sw_exit: pop si ;restore pop di ; regs pop bx ; from pop es ; stack pop bp ret 8 screenwrite endp ;;;;;;;;;;;;;;;;;;;;; ;moves bytes from v1addr to v2addr ;procedure move(v1addr,v2addr,bytes : integer); move proc near push bp mov bp,sp ;BP points to stack push es ;save push di ; regs push si ; on stack mov ax,ds ;AX = DS mov es,ax ;ES = AX = DS mov si,[bp+8] ;SI points to v1addr mov di,[bp+6] ;DI points to v2addr mov cx,[bp+4] ;CX number of bytes to move rep movsb ;mass move pop si ;restore pop di ; regs pop es ; from stack pop bp ret 6 move endp ;;;;;;;;;;;;;;;;;;;;; ;positions cursor to col, row values ;procedure setxy(col,row : integer) setxy proc near push bp mov bp,sp ;BP points to stack push bx ;preserve BX mov bh,0 ;page is 0 mov ah,2 ;for BIOS call to move cursor mov dh,[bp+4] ;DH = row dec dh ;normalize mov dl,[bp+6] ;DL = col dec dl ;normalize int 10h ;BIOS will move it pop bx ;restore BX pop bp ret 4 setxy endp ;;;;;;;;;;;;;;;;;;;;; ;fills designated string with specified character ;procedure fillstr(var target : string; num,ch : integer); fillstr proc near push bp mov bp,sp ;BP points to stack push es ;save ES mov ax,ds ;AX = DS mov es,ax ;ES = AX = DS mov di,8[bp] ;DI points to target string mov cx,6[bp] ;CX = num cmp cx,80 ;longer than 80 char? jg poof ;yes, depart mov al,byte ptr 4[bp] ;AL = ch cld ;for forward move rep stosb ;store ch in string mov al,0 ;AL = 0 stosb ;for end of string byte poof: pop es ;restore ES pop bp ret 6 fillstr endp ;;;;;;;;;;;;;;;;;;;;; ;adds two long integers - return result in total ;procedure addlong(var total,n1,n2 : longint) addlong proc near push bp mov bp,sp push bx ;save push di ; regs push si ; on stack mov si,[bp+6] ;SI points to n1 low word mov di,[bp+4] ;DI points to n2 low word mov bx,[bp+8] ;BX points to total low word mov cx,2 ;CX = 2 clc ;clear carry add_em: mov ax,[si] ;AX = n1 inc si ;bump SI inc si ;SI now points to n1 hi word adc ax,[di] ;add n1 to n2 inc di ;bump di inc di ;DI now points to n2 hi word mov [bx],ax ;store in total lo word inc bx ;bump bx inc bx ;BX now points total hi word loop add_em ;do again for hi word pop si ;restore pop di ; regs pop bx ; from stack pop bp ret 6 addlong endp ;;;;;;;;;;;;;;;;;;;; ;converts a long integer into a string; ;procedure longstr( var long : longint; var str : longstr) longstr proc near push bp mov bp,sp ;BP points to stack push ds ;save push es ; regs push bx ; on push si ; the push di ; stack jmp over_dat ;skip over data temp_buff db 5 dup(0) lstr db 12 dup(0) over_dat: cld ;set direction to forward mov ax,ds ;AX = DS push ax ;save AX, we need DS later mov bx,[bp+6] ;BX points to long low word mov dx,[bx+2] ;DX points to long hi word mov bx,[bx] ;BX = long low word mov ax,cs ;AX = CS mov ds,ax ;DS = AX = CS mov es,ax ;ES = AX = CS lea di,temp_buff ;DI points to buffer mov cx,5 ;CX = 5 (for 10 digits) mov al,0 ;AL = 0 clear: stosb ;store a 0 loop clear ;fill buffer with zeros mov cx,32 ; test dx,8000h ;is low word negative? jz no_neg ;no, skip code not dx ;DX = -DX not bx ;BX = -BX add bx,1 ;BX = BX + 1 adc dx,0 ;adjust for carry no_neg: std ;set direction to back l_loop: push cx ;save counter mov cx,5 ;five bytes=10 digits lea si,temp_buff ;SI points to buffer add si,4 ;SI points to buffer end mov di,si ;DI = SI shl bx,1 ;grab a bit rcl dx,1 ;and then rotate adjust: lodsb ;load AL with byte adc al,al ;add carry daa ;decimal adjust stosb ;store in temp_buff loop adjust ;keep going pop cx ;restore counter loop l_loop ;and do again cld ;set flag to forward lea di,lstr ;DI points to lstr xor dx,dx ;DX = 0 lea si,temp_buff ;SI points to buffer mov cx,10 ;CX = 10 characters xor bx,bx ;BX = 0 x_str: test cx,1 ;high or low? jnz y_str ;low lodsb ;AL = char mov ah,al ;AH = AL push cx ;save CX mov cl,4 ;CL = 4 shr al,cl ;shift AL right 4 pop cx ;restore CX jmp z_str ;do a character y_str: mov al,ah ;low part and al,0Fh ;and it z_str: test al,0Fh ;is it zero? jnz w_str ;no or bx,bx ;a leading zero jz l_next ;no w_str: inc bx ;BX has length or al,'0' ;AL = ASCII char stosb ;store in string l_next: loop x_str ;continue add bx,dx ;add 0 jnz l_done ;are we done? inc bx ;bump length mov al,'0' ;make 0 stosb ;store it l_done: cld ;back to forward mov byte ptr [di],0 ;end of string byte pop ax ;restore AX mov es,ax ;ES = DS lea si,lstr ;SI points to lstr mov di,[bp+4] ;DI points to str mov cx,12 ;we'll move all rep movsb ;move them pop di ;restore pop si ; regs pop bx ; from pop es ; the pop ds ; stack pop bp ret 4 longstr endp ;;;;;;;;;;;;;;; ;hides the cursor hide_cursor proc near mov ah,1 ;cursor size function mov ch,20h ;set it to 20h int 10h ;BIOS does it ret hide_cursor endp ;;;;;;;;;;;;;;; ;saves the DOS cursor for later restoration save_cursor proc near jmp get_it ;jump past data save_curs dw 0 get_it: mov ah,3 ;get cursor size function mov bh,0 ;page is 0 int 10h ;BIOS does it mov cs:save_curs,cx ;CX has size - save it ret save_cursor endp ;;;;;;;;;;;;;;; ;restores the saved DOS cursor rest_cursor proc near mov cx,cs:save_curs ;retrieve cursor size mov ah,1 ;set cursor size function int 10h ;BIOS does it ret rest_cursor endp toolcode ends end