C/C++ Interactive Reference Guide

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Text File | 1987-12-17 | 29.1 KB | 983 lines

;------------------------------------------------------------------ ; gedio.a -- Screen and keyboard interface routines for the PC ; Specific to DeSmet C ; ; last modified - 08/02/87 ;------------------------------------------------------------------ ;------------------------------------------------------------------ ; !!! PLEASE NOTE !!! ; This is not quite the same as pcio.a from DeSmet - ; I've made some changes here and there for use with ged. ; ; Renamed for ged 1.10 ; ; Have changed all Desmet functions that use x,y co-ords ; to work as col, row. ; Mel Tearle ;------------------------------------------------------------------ ;------------------------------------------------------------------ ; data starts here ;------------------------------------------------------------------ dseg ; In this implementation, all special and function keys are translated ; to the following values. ; control key translations - mapped into cursor-pad. up_char equ 5 ;arrow up down_char equ 24 ;arrow down left_char equ 19 ;arrow left right_char equ 4 ;arrow right bol_char equ 15 ;Home eol_char equ 16 ;End pageup_char equ 18 ;PgUp pagedown_char equ 3 ;PgDn Del_char equ 7 ;Del ; function key definitions M1 equ 128 M2 equ 129 M3 equ 130 M4 equ 145 M5 equ 132 M6 equ 133 M7 equ 134 M8 equ 135 M9 equ 136 M10 equ 137 ; special keys - toggles and keypress Insert_key equ 138 Caps_Lock_on equ 139 Caps_Lock_off equ 140 Alt_key equ 146 grey_minus equ 142 grey_plus equ 143 ; the table that is used to make the translation ; note - not all used convert: db 72, up_char db 80, down_char db 75, left_char db 77, right_char db 71, bol_char db 79, eol_char db 73, pageup_char db 81, pagedown_char db 78, grey_plus db 74, grey_minus db 82, Insert_key db 83, Del_char db 59, M1 db 60, M2 db 61, M3 db 62, M4 db 63, M5 db 64, M6 db 65, M7 db 66, M8 db 67, M9 db 68, M10 db 0, 255 ;illegal character ; equates for bios interface. ; the interrupt and codes for the screen interface interrupt. video equ 10h ;interrupt for dealing with screen mode equ 0 ;code for setting new screen mode curtype equ 1 ;code for setting new cursor type setcur equ 2 ;code for addressing cursor readcur equ 3 ;code for reading cursor location readlp equ 4 ;code for reading light pen position setpage equ 5 ;code to select active page scrollup equ 6 ;code to scroll screen up scrolldn equ 7 ;code to scroll screen nown readch equ 8 ;code to read a character from screen writeach equ 9 ;code to write char and attributes writech equ 10 ;code to write character only setpal equ 11 ;code to set new setpal or border wdot equ 12 ;code to write a dot rdot equ 13 ;code to read a dot wtty equ 14 ;code to write as if teletype state equ 15 ;code to find current screen status ; used in set_video mono_adr equ 0b000h ;mono adapter graph_adr equ 0b800h ;graphics adapter* vadrs: dw 0 ; the interrupt and codes for the keyboard interface. keyboard equ 16h ;interrupt 16 to deal with keyboard cicode equ 0 ;code for reading a character cstscode equ 1 ;reports if character is ready kbstatus equ 2 ;get keyboard status - shifts, caplocks kbset: db 0 ; caution: must change column number if 40 column mode crt_cols equ 80 ; variables available to a C88 program public scr_cols_, scr_rows_, scr_scrollup_, scr_scrolldown_ public scr_mode_, scr_page_, scr_attr_, scr_window_top_ scr_cols_: dw crt_cols ;current number of columns ; note- make 25 for ms-dos and 24 for cp/m as cp/m steals the bottom ; line. scr_rows_: dw 24 ;current number of rows, for ged, was 25 scr_mode_ db 0 ;current screen mode scr_page_ db 0 ;current page scr_attr_ db 7 ;current attributes for screen ;7 is white letters on black scr_window_top_ db 1 ;first line to scroll, was 0 ;------------------------------------------------------------------ ; code starts here ;------------------------------------------------------------------ cseg ;------------------------------------------------------------------------- ; SCR_SETUP_ scr_setup must be called before any use of any ; other routine unless the starting mode is 80X25 ; character mode (3,4 or 7). Must be called for monochrome ; (mode 7) for scr_curson to set a proper cursor. ; ; Usage: mode = scr_setup(); ;------------------------------------------------------------------------- public scr_setup_ scr_setup_: push bp mov bp, sp mov ah,state ;get current state int video mov scr_mode_, al ;current mode mov cl, ah ;make cols a word mov ch,0 mov scr_cols_,cx ;40 or 80 columns mov scr_page_,bh mov scr_attr_,7 ;set to white chars on black cmp al, 4 ;see if a character mode jc got_attr cmp al, 7 ;7 is for graphics mode jz got_attr mov scr_attr_,0 ;attribute is zero in graphics got_attr: mov ah,0 ;return int containing mode push ax ;slight detour call set_video_ ;get display address pop ax pop bp ret ;------------------------------------------------------- ; SCR_TERM_ do any required termination. ; ; Usage: scr_term(); ;------------------------------------------------------- public scr_term_ scr_term_: ret ;------------------------------------------------------- ; SCR_SETMODE_ set a new screen mode ; ; Usage: scr_setmode(new mode); ;------------------------------------------------------- public scr_setmode_ scr_setmode_: push bp mov bp,sp mov al,[bp+4] ;new mode value mov ah,mode int video ;set new mode call scr_setup_ ;remember new values pop bp ret ;------------------------------------------------------- ; SCR_XY_ sets cursor at any location. ; ; Usage: scr_xy(column,row); ;------------------------------------------------------- public scr_xy_ scr_xy_: push bp ;save from bios mov bp, sp mov dx,[bp+4] ;col mov ax,[bp+6] ;row mov dh, al mov bh,scr_page_ ;force page zero mov ah,setcur ;set cursor location int video ;call bios pop bp ret ;------------------------------------------------------- ; SCR_CLR_ clear entire screen ; ; Usage: scr_clr(); ;------------------------------------------------------- public scr_clr_ scr_clr_: push bp mov bp, sp mov al,0 ;ask for a clear window xor cx,cx ;start at 0,0 mov dh,byte scr_rows_ ;last line dec dh mov dl,byte scr_cols_ ;clear entire width dec dl ;last column is width-1 mov bh,scr_attr_ ;attributes for new blanks mov ah,scrollup ;ask for a scrollup to clear int video ;do the clear pop bp ret ;------------------------------------------------------- ; SCR_CLRL_ clear rest of line. ; ; Usage: scr_clrl(); ;------------------------------------------------------- public scr_clrl_ scr_clrl_: push bp mov bp, sp mov bh,scr_page_ mov ah,readcur ;see where we are int video mov cl,byte scr_cols_ ;calc how many chars left in line sub cl,dl ;number left mov ch,0 ;number of blanks needed mov al,' ' ;write blanks mov bl,scr_attr_ ;normal attributes mov bh,scr_page_ ;page number mov ah,writeach ;write the blanks int video pop bp ret ;------------------------------------------------------- ; SCR_CLS_ clear rest of screen starting at y ; set line pointer, clear screen, reset line pointer ; ; Usage: scr_cls(y); ;------------------------------------------------------- public scr_cls_ scr_cls_: push bp mov bp,sp mov dx,0 ;hard-code column at 0 mov ax,[bp+4] ;get row mov dh,al mov bh,scr_page_ ;force page zero mov ah,setcur ;set cursor location int video ;call bios call scr_clrl_ ;clear rest of line mov al,0 ;ask for a clear window mov ch,[bp+4] ;re-use row inc ch ;bump row cmp ch,byte scr_rows_ ;see if in last line jz cleared ;all done mov cl,0 ;first column mov dh,byte scr_rows_ ;24 is the last line dec dh mov dl,byte scr_cols_ ;clear entire width dec dl ;last column is width-1 mov bh,scr_attr_ ;attributes for new blanks mov ah,scrollup ;ask for a scrollup to clear int video ;do the clear cleared: mov dx,0 ;set column again mov ax,[bp+4] ;get row mov dh,al mov bh,scr_page_ ;force page zero mov ah,setcur ;set cursor location int video ;call bios pop bp ret ;-------------------------------------------------------- ; scr_delete_ clear rest of line starting at column, row. ; ; Usage: scr_delete(x,y); ;-------------------------------------------------------- public scr_delete_ scr_delete_: push bp mov bp, sp mov dx, [bp+4] ;col mov ax, [bp+6] ;row mov dh, al mov bh, scr_page_ ;force page zero mov ah, setcur ;set cursor location int video ;call bios mov cl, byte scr_cols_ ;calc how many chars left in line sub cl, dl ;number left mov ch, 0 ;number of blanks needed mov al, ' ' ;write blanks mov bl, scr_attr_ ;normal attributes mov bh, scr_page_ ;page number mov ah, writeach ;write the blanks int video pop bp ret ;-------------------------------------------------------- ; SCR_SCUP_ scroll text up leaving top lines alone. ; ; Usage: scr_scup(); ;-------------------------------------------------------- public scr_scup_ scr_scup_: ;scroll last line, screen from line ;scr_windor_top to end mov ax,scr_cols_ ;need last column of screen dec ax push ax mov ax,scr_rows_ ;scroll through last line dec ax push ax xor ax,ax ;from column 0 push ax mov al,scr_window_top_ ;leave top line alone push ax mov al,1 push ax ;scroll by 1 call scr_scrup_ ;do the scroll add sp,10 ;clear arge ret ;--------------------------------------------------------------- ; SCR_SCRUP_ Scroll the screen up. The window is scrolled ; up nline lines. A zero nline will clear the ; window. Top left of the screen in 0,0. ; ; Usage: scr_scrup(nline,fromrow,fromcol,torow,tocol); ;--------------------------------------------------------------- public scr_scrup_ scr_scrup_: push bp mov bp,sp mov al,[bp+4] ;number of lines mov ch,[bp+6] ;starting row mov cl,[bp+8] ;starting column mov dh,[bp+10] ;ending row mov dl,[bp+12] ;ending column mov bh,scr_attr_ ;current attribute mov ah,scrollup int video ;do the scroll pop bp ret ;------------------------------------------------------------- ; SCR_SCDN_ scroll all but the top lines down one. ; ; Usage: scr_scdn(); ;------------------------------------------------------------- public scr_scdn_ scr_scdn_: mov ax,scr_cols_ ;need last column of screen dec ax push ax mov ax,scr_rows_ ;scroll through last line dec ax push ax xor ax,ax ;from column 0 push ax mov al,scr_window_top_ ;leave top lines alone push ax mov al,1 push ax ;scroll by 1 call scr_scrdn_ ;do the scroll add sp,10 ;clear arge ret ;--------------------------------------------------------------- ; SCR_SCRDN_ scroll the screen down. the window is scrolled ; down nline lines. A zero nline will clear the ; window. Top left of the screen in 0,0. ; ; Usage: scr_scrdn(nline,fromrow,fromcol,torow,tocol); ;--------------------------------------------------------------- public scr_scrdn_ scr_scrdn_: push bp mov bp,sp mov al,[bp+4] ;number of lines mov ch,[bp+6] ;starting row mov cl,[bp+8] ;starting column mov dh,[bp+10] ;ending row mov dl,[bp+12] ;ending column mov bh,scr_attr_ ;current attribute mov ah,scrolldn int video ;do the scroll pop bp ret ;--------------------------------------------------------------- ; SCR_CO_ write a character to the screen. this ; routine increments the cursor position ; after writing. normal C88 puts and printf ; statements can also be used to write to the ; screen. ; ; Usage: scr_co(character); ;--------------------------------------------------------------- public scr_co_ scr_co_: push bp mov bp, sp mov al, [bp+4] ;character to write mov bh,scr_page_ mov ah, wtty ;use tty write routine int video pop bp ret ;--------------------------------------------------------------- ; SCR_CI_ keyboard input. function and soft keys are ; translated. see equates for values. ; ; Usage: character = scr_ci(); ;--------------------------------------------------------------- public scr_ci_ scr_ci_: push bp mov ah, cicode ;ask for a keyboard character int keyboard ;do interrupt cmp ax, 4a2dh ;test for grey keys je minus_grey cmp ax, 4e2bh ;grep plus by default jne continue mov al, grey_plus jmp not_special minus_grey: mov al, grey_minus jmp not_special continue: cmp al, 0 ;is low byte equal to zero? jne not_special ;it's not - must be ascii so return it mov bx, offset convert ;else convert to special key ci_loop: cmp byte[bx], 0 ;are we done? jz got_it ;it's zero - so end routine cmp ah, byte[bx] ;else does it equal the high byte? je got_it ;got a hit - finish up add bx, 2 ;else bump bx jmp ci_loop got_it: inc bx ;get return value from convert mov al, [bx] ;put it in low byte not_special: mov ah, 0 ;normal return pop bp ret ;--------------------------------------------------------------- ; SCR_CSTS_ return character if any available. otherwise ; return zero. ; ; Usage: character = scr_csts(); ;--------------------------------------------------------------- public scr_csts_ scr_csts_: push bp mov ah, cstscode ;anything there? int keyboard mov ax, 0 jz kbstat call scr_ci_ ;else get the character jmp fin kbstat: call get_kbstat_ fin: pop bp ret ;--------------------------------------------------------------- ; get_kbstat_ check status of insert key, capslock and alt key ; return special value or zero. ; ; Usage: internal routine used by scr_csts(); ;--------------------------------------------------------------- public get_kbstat_ get_kbstat_: push bp mov ah, kbstatus ;get keyboard status int keyboard cmp al, kbset ;set if keyboard status is changed je return_0 ;if same - return 0 mov kbset, al ;new keyboard toggle - save it test al, 08h ;test for alt press jnz alt_pressed test al, 40h ;test for caps lock on jnz caps_on and al, 40h ;reverse bits test al, 40h ;test if caps lock off jz caps_off ;if zero then toggled off return_0: mov al, 0 ;return 0 - no hits jmp fin3 alt_pressed: mov al, Alt_key jmp fin3 caps_on: mov al, Caps_Lock_on jmp fin3 caps_off: mov al, Caps_Lock_off fin3: mov ah, 0 pop bp ret ;--------------------------------------------------------------- ; caps_on_ check status of capslock only ; if on then return CAPSLKON ; ; Usage: if ( caps_on() ) do something ;--------------------------------------------------------------- public caps_on_ caps_on_: push bp mov ah, kbstatus ;get keyboard status int keyboard test al, 40h ;test for caps lock on jnz caps_on1 mov al, 0 ;return 0 - no hits jmp fin4 caps_on1: mov al, Caps_Lock_on fin4: mov ah, 0 pop bp ret ;--------------------------------------------------------------- ; GET_GRAPHIC_ return the next char in buffer - unfiltered ; ; Usage: character = get_graphic(); ;--------------------------------------------------------------- public get_graphic_ get_graphic_: push bp mov ah, cicode ;ask for a keyboard character int keyboard ;do interrupt mov ah, 0 ;normal return pop bp ret ;--------------------------------------------------------------- ; SCR_CURSOFF_ turn cursor off. ; ; Usage: scr_cursoff(); ;--------------------------------------------------------------- public scr_cursoff_ scr_cursoff_: push bp ;save registers cmp scr_mode_,4 ;see if graphics jc text_coff cmp scr_mode_,7 jnz no_cur text_coff: mov cx,0f00h ;should turn cursor off new_cur: mov ah,curtype ;set a new cursor type int video no_cur: pop bp ret ;--------------------------------------------------------------- ; SCR_CURSON_ turn cursor back on. ; ; Usage: scr_curson(); ;--------------------------------------------------------------- public scr_curson_ scr_curson_: push bp mov cx,0c0dh ;assume monocrome cmp scr_mode_,7 ;true is mono jz new_cur ;set it mov cx,0607h ;assume color card in text mode cmp scr_mode_,4 ;color text is 0 to 3 jc new_cur pop bp ;do nothing if in graphics mode ret ;--------------------------------------------------------------- ; SCR_APUTS_ write a string and attributes to the screen. ; goto col, row first. the cursor is moved normally ; ; Usage: scr_aputs(x,y,"Print This",attribute); ;--------------------------------------------------------------- public scr_aputs_ scr_aputs_: push bp mov bp, sp mov dx, [bp+4] ; col mov ax, [bp+6] ; row mov dh, al mov bh, scr_page_ ; force page mov ah, setcur ; set cursor location int video ; dx is cursor location, bh is page mov si, [bp+8] ; string pointer mov cx, 1 ; number of characters to write mov bl, [bp+10] ; attribute naputs: cld lodsb ; next character to write or al, al ; zero at end jz eaputs cmp al, 10 ; look for LF jnz normal_ap ap_scroll: mov bp, sp ; reset pointer to next char mov [bp+4], si mov al, 13 ; use tty output to scroll screen mov ah, wtty int video ; write cr,lf mov ah, wtty mov al, 10 int video pop bp jmp scr_aputs_ ; start over normal_ap: mov bh, scr_page_ ; do a scroll up mov ah, writeach ; write char and attr int video ; write character and attributes inc dl ; next column cmp dl, crt_cols ; see if wrapping around jc set_loc mov dl, 0 ; at start of column inc dh ; at next row cmp dh, byte scr_rows_ ;see if need a scroll jc set_loc jmp ap_scroll ; do a scroll up set_loc: mov ah, setcur ; move the cursor int video jmp naputs eaputs: pop bp ret ;------------------------------------------------------------------- ; SCR_PUTCH_ write a character to the screen with attribute set. ; see scr_aputs and scr_co ; ; Usage: scr_putch( character, attribute ); ;------------------------------------------------------------------- public scr_putch_ scr_putch_: push bp mov bp,sp mov ah,readcur ;see where we are mov bh,scr_page_ int video ;dx is cursor location, bh is page mov al,[bp+4] ;character to write mov bl,[bp+6] ;attribute of char mov bh,scr_page_ ;set page number mov cx,1 ;write just one char mov ah,writeach ;write char and attr int video inc dl ;move to next column mov ah,setcur ;move the cursor int video pop bp ret ;---------------------------------------------------------- ; The following routines get_mode_, calc_video_, ; set_video_ and scr_putstr were adapted from ; Computer Language Magazine - January 1986 ; "Assembly Video Routines for your P.C.", Thomas Webb ;---------------------------------------------------------- ;---------------------------------------------------------- ; GET_MODE_ get video mode ; ; Usage: internal subroutine used in scr_putstr ;---------------------------------------------------------- public get_mode_ get_mode_: push bp mov ax, 0 mov ah, 15 int 10h pop bp ret ;---------------------------------------------------------- ; CALC_VIDEO_ calculate offset into video buffer ; set begining location and attribute ; ; Usage: internal subroutine used in scr_putstr ;---------------------------------------------------------- public calc_video_ calc_video_: mov ax,crt_cols mul dx add ax,cx shl ax,1 ret ;------------------------------------------------------- ; SET_VIDEO_ set video address ; ; Usage: internal subroutine used in scr_setup ;------------------------------------------------------- public set_video_ set_video_: call get_mode_ cmp al, 7h jne adp_graphics mov ax, mono_adr jmp return adp_graphics: mov ax, graph_adr return: mov vadrs, ax ret ;---------------------------------------------------------- ; SCR_PUTSTR_ write a string directly to video buffer ; at col, row location with attribute. ; Doesn't change cursor position. ; ; Usage: scr_putstr( x, y, string, attribute ); ;---------------------------------------------------------- public scr_putstr_ scr_putstr_: push es ;save es push bp ;save bp mov bp,sp ;move stack pointer to bp mov dx,[bp+8] ;get col mov cx,[bp+6] ;get row ;locate position in video buffer - calc video routine moved here ;to save call mov ax,crt_cols ;get screen width mul dx ; add ax,cx ; shl ax,1 ; mov di,ax ;return position mov si,[bp+10] ;get start of string mov dh,[bp+12] ;get attribute mov es,vadrs ;move absolute display address to es str_loop: mov dl,byte [si] ;get the next byte from the string cmp dl,0 ;test for end of string je str_exit ;if equal to '\0' then goto exit mov es:word [di],dx ;move a word into screen display add di,2h ;bump display index inc si ;bump index to string jmp str_loop ;goto loop-top str_exit: pop bp ;restore bp pop es ;restore es ret ;--------------------------------------------------------------- ; SCR_APUTCH_ write a character to the screen with ; attribute set. see scr_aputs and scr_co ; ; Usage: scr_aputch(x,y,char,attribute); ; ; After getting this to work found that it isn't that fast. ; However, it's a good replacement for gotoxy() scr_putch() ; if you're only writing one char to a specific location. ;--------------------------------------------------------------- public scr_aputch_ scr_aputch_: push es push bp mov bp, sp mov dx, [bp+8] ; get col mov cx, [bp+6] ; get row call calc_video_ ; locate position in video buffer mov di, ax ; return position mov dl, [bp+10] ; get char mov dh, [bp+12] ; get attribute mov ax, vadrs ; get video address mov es, ax ; move buffer address to es mov es:word [di], dx pop bp pop es ret ;--------------------------------------------------------------- ; SCR_SINP_ screen input (read character from the screen). ; ; Usage: character = scr_sinp(); ;--------------------------------------------------------------- public scr_sinp_ scr_sinp_: push bp ;save the registers mov bh,scr_page_ mov ah,readch ;code to read a character int video ;al is letter, ah=attributes or al,al ;zero returned instead of blank in ;graphics mode jnz ret_ch mov al,' ' ret_ch: mov ah,0 ;kill the attributes pop bp ret ;--------------------------------------------------------------- ; SCR_MARK mark the current character on the screen. ; Used to delimit block areas in SEE. Just write ; an X or something if reverse video is not available. ; ; Usage: scr_mark(current character); ;--------------------------------------------------------------- public scr_mark_ scr_mark_: ;mark the passed char, cursor does not advance push bp mov al,219 ;just write a block character mov bl,scr_attr_ ;normal attributes mov cx,1 ;one character mov bh,scr_page_ ;page number mov ah,writeach ;write char and attr int video ;write character and attributes pop bp ret ; that's all