Computer Select (Limited Edition)

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Assembly Source File | 1992-03-09 | 24.4 KB | 747 lines

page 64,132 ;======================================================================== ; SPRINTER ; Cursor Speedup Program ; Written 1992 by Douglas Boling ;======================================================================== ;======================================================================== ; BIOS_DATA segment ;======================================================================== bios_data segment at 40h org 17h bios_shift_stat db ? ;Shift status of keyboard org 1ah keybuff_head dw ? ;Pointer to first entry in org 1ch ; BIOS keyboard buffer. keybuff_tail dw ? ;Pointer to last entry in org 80h ; BIOS keyboard buffer. keybuff_start dw ? ;Pointer to beginning of org 82h ; BIOS keyboard buffer. keybuff_end dw ? ;Pointer to end of BIOS org 96h ; keyboard buffer. kb_status db ? ;Status of keyboard bios_data ends ;======================================================================== ; Code segment (code and data) ;======================================================================== code segment para public'code' assume cs:code org 2ch env_seg dw ? ;Pointer to environment seg org 80h command_tail db ? org 100h begin: jmp initialize program db 13,10,"Sprinter 1.0 " copyright db "Copyright (c) 1992 Douglas Boling",13,10 db "First published in PC Magazine, May 26, 1992",13,10 db "For help type: sprinter /?",13,10 db 13,10,"$",1Ah ;------------------------------------------------------------------------ ; Memory locations required for program. ;------------------------------------------------------------------------ enable_flag db 1 ;1 = enabled, 0 = disabled shift_status db 0 ;bits represent shift status last_code db 0 ;Previous scan code cursor_code dw 0 ;Cursor code currently active shift_mask db 11h ;Activate using Alt keys make_kept db 0 ;key not passed to BIOS key_count db 2 ;Number of keys pushed/int scanlist_ptr label dword ;Pointer to list of scan codes dw offset scanlist ;Offset dw ? ;Segment scanlist db 48h,4bh,4dh,50h,49h,51h ;Cursor key scancodes shiftlist db 38h,1dh,2ah,36h ;Alt, Ctl, and L/R shift codes scanlist_end = $ environment_flg db 1 ;1 = environment still owned int8h dd ? ;int 8h vector (Timer) int9h dd ? ;int 9h vector (Keyboard) ;======================================================================== ; TIMERINT receives control when an interrupt 8 is generated. ;======================================================================== timerint proc far assume cs:code,ds:nothing,es:nothing pushf call cs:[int8h] ;Go to BIOS routine cmp cs:enable_flag,0 ;See if program enabled je timer_exit1 ;No, exit push ax mov al,cs:shift_status ;See if shift combination mov ah,cs:shift_mask test al,ah je timer_exit ;No, exit not ah ;See if any other shift key and al,ah ; is active. mov ax,cs:cursor_code ;Get saved cursor key code or ax,ax ;See if cursor key active je timer_exit ;No, exit ;------------------------------------------------------------------------ ;If shift combination set and cursor key pressed, put scancode into buffer. ;------------------------------------------------------------------------ push ds ;Yes, Save registers needed push bx ; for keyboard buffer work. push cx push di mov bx,40h ;DS = BIOS data segment mov ds,bx assume ds:bios_data cli ;No ints when loading buffer mov bx,keybuff_tail ;Get pointer to end of buffer mov di,bx ;Copy to see if buffer full xor ch,ch mov cl,cs:key_count ;Get num of keys to push timer0: call advance_keyptr ;Check ahead in buffer. jc timer1 ;If full, goto end mov [bx],ax ;Put character in queue mov bx,di ;Update pointer loop timer0 timer1: mov keybuff_tail,bx ;Save updated keyboard ptr sti ;Allow interrupts pop di ;Restore registers pop cx pop bx pop ds timer_exit: pop ax timer_exit1: iret ;Return timerint endp ;======================================================================== ; KEYBINT receives control when an interrupt 9 is generated. ;======================================================================== keybint proc far assume cs:code,ds:nothing,es:nothing push ax cmp cs:enable_flag,0 ;See if enabled. If not jump je go_kb_int1 ; directly to BIOS. in al,64h ;Read keyboard status port. test al,1 ;See if output buffer full. je go_kb_int1 ;No, must be some other I/O. push cx push di push ds mov ax,cs mov ds,ax ;DS = CS assume ds:code in al,60h ;Read keyboard data port. sti ;Enable interrupts ;------------------------------------------------------------------------ ;Compare scan code with list of keys. ;------------------------------------------------------------------------ push es les di,scanlist_ptr ;Point to list of scan codes. mov cx,offset scanlist_end - offset scanlist mov ah,al ;Copy scan code and al,7fh ;Remove break bit from code cld repne scasb ;Scan list pop es jne go_kb_int ;Scancode not in list go BIOS sub cx,offset scanlist_end - offset scanlist neg cx ;Make positive sub cl,offset shiftlist - offset scanlist + 1 jb cursorkey_found ;If first 6 codes, cursor code ;------------------------------------------------------------------------ ;Shift key scancode. Set or clear bit in shift status. ;------------------------------------------------------------------------ cmp last_code,0e0h ;See if extended code jne shiftkey1 ;If extended, increase shift add cl,4 ; for right alt or ctl keys. shiftkey1: mov al,1 ;Use al as a bit set register shl al,cl ;Shift bit by index into list test ah,80h ;See if make or break code jne shiftkey_break ;Break, jump. or shift_status,al ;Make, set bit in shift status jmp short go_kb_chk ;Goto BIOS shiftkey_break: push ax not al ;Invert mask to clear bit and shift_status,al ;Clear bit pop ax ;------------------------------------------------------------------------ ;If proper accelerator shift key, don't pass key to BIOS ;------------------------------------------------------------------------ go_kb_chk: test al,shift_mask ;If this is the proper je go_kb_int ; shift and a cursor key cmp cursor_code,0 ; is down, don't pass scan je go_kb_int ; code to BIOS. test ah,80h ;See if make or break jne go_kb_chk1 mov make_kept,1 ;Indicate make code kept jmp short go_kb_int jmp short keyb_iret go_kb_chk1: mov make_kept,0 ;Clear flag. ;------------------------------------------------------------------------ ;Exit to BIOS keyboard interrupt routine. ;------------------------------------------------------------------------ go_kb_int: mov last_code,ah ;Save current code pop ds ;Restore registers pop di pop cx go_kb_int1: pop ax jmp cs:[int9h] ;Go to BIOS routine ;------------------------------------------------------------------------ ;Discard key. Reset the keyboard and signal end-of-interrupt to the 8259 ;------------------------------------------------------------------------ keyb_iret: call reset_keyboard ;Reset keyboard mov last_code,ah ;Save current code pop ds ;Restore registers pop di pop cx pop ax iret ;Return to program ;------------------------------------------------------------------------ ;Cursor key scancode, check for extended key or number key and numlock on. ;------------------------------------------------------------------------ cursorkey_found: xor al,al ;Assume 0 extended scancode cmp last_code,0e0h ;See if extended key jne cursorkey_numpad mov al,0e0h ;Load extended keycode. jmp short cursorkey1 cursorkey_numpad: push es push ax mov ax,40h ;ES = BIOS data segment mov es,ax assume es:bios_data pop ax test es:bios_shift_stat,20h ;See if numlock active pop es assume es:nothing jne go_kb_int ;If so, not a cursor key. ;------------------------------------------------------------------------ ;Check for break code. If break, clear stored scan code. ;------------------------------------------------------------------------ cursorkey1: test ah,80h ;See if break je cursorkey_make ;No, continue xor ax,ax ;Yes, clear last code cursorkey_make: mov cursor_code,ax ;Save cursor code mov al,shift_status ;See if shift combination test shift_mask,al jne keyb_iret jmp go_kb_int ;Yes, goto BIOS keybint endp ;======================================================================== ; ADVANCE KEYPTR moves the keyboard buffer pointer to the next free ; location in the BIOS keyboard buffer. ; Entry: DI - keyboard head pointer ; Exit: CF - Set if keyboard buffer full ;======================================================================== advance_keyptr proc near assume cs:code,ds:bios_data inc di ;Point to next entry inc di cmp di,keybuff_end ;See if at the end of the jne advance1 ; buffer. If so, reset the mov di,keybuff_start ; pointer to the start. advance1: cmp di,keybuff_head ;See if the buffer is full je advance_full clc jmp short advance_exit advance_full: stc advance_exit: ret advance_keyptr endp ;======================================================================== ; RESET KEYBOARD resets the interrupts controller. Used when discarding ; scan codes. ;======================================================================== reset_keyboard proc near push ax cli ;Disable interrupts in al,61h ;Reset the keyboard mov ah,al ; controller or al,80h out 61h,al mov al,ah out 61h,al mov al,20h ;Signal end-of-interrupt to out 20h,al ; the interrupt controller sti ;Enable interrupts pop ax ret reset_keyboard endp end_of_code = $ ;======================================================================== ; End of nonresident code. ;======================================================================== infomsg1 db "The available commands are:" db 13,10,"/e Enable acceleration" db 13,10,"/d Disable acceleration" db 13,10,"/u Uninstall program" db 13,10,"/s x Set acceleration speed where x" db " is between 1 and 9" db 13,10,"/k xx Set shift key where xx is one of" db " the following:" db 13,10," a Alt key" db 13,10," c Ctl key" db 13,10," s Shift key" db 13,10," lx to specify only the left key" db 13,10," rx to specify only the right key" db 13,10,"/? Print this message$" infomsg2 db "Sprinter removed$" infomsg3 db "Sprinter installed",13,10,"$" infomsg4 db "Acceleration key is " keytag db 15 dup (" "),13,10 db "Acceleration speed is " speedtag db 2 dup (" "),13,10,10,"$" errmsg1 db "Bad commmand$" errmsg2 db "Can't remove$" errmsg3 db "Bad shift key$" errmsg4 db "Not installed$" errmsg5 db "Bad key speed$" end_msg db 13,10,"$" left_tag db "<Left>",0 right_tag db "<Right>",0 alt_tag db "<Alt>",0 ctrl_tag db "<Ctrl>",0 shift_tag db "<Shift>",0 commands db 'edksu?' ;Letters corrsponding to the commands_end = $ ; command line switches. jumptable: dw offset enable ;Command routine jump table dw offset disable dw offset keyset dw offset speedset dw offset uninstall dw offset display_help shiftkeys db 'lracs' ;Letters corrsponding to the shiftkeys_end = $ ; shift keys allowed. other_seg dw 0 ;Segment of installed code alrdy_installed db 0 ;bcopy already installed flag remove_flag db 0 ;1 = uninstall ;======================================================================== ; INITIALIZE ;======================================================================== initialize proc near assume cs:code, ds:code cld ;clear DF mov ah,9 ;display copyright message mov dx,offset program int 21h ;------------------------------------------------------------------------ ;See if a copy is already resident in memory. ;------------------------------------------------------------------------ mov word ptr [begin],0 ;initialize fingerprint mov bx,0a000h ;Start at UMBs mov ax,cs ;keep CS value in AX find_copy: inc bx ;increment search segment value mov es,bx cmp ax,bx ;not installed if current je find_copy1 ; segment is looped back to mov si,offset begin ;search this segment for ASCII mov di,si ; fingerprint mov cx,16 repe cmpsb jne find_copy ;loop back if not found inc alrdy_installed ;Clear installed flag find_copy1: mov other_seg,es ;save installed code segment push cs ;ES = CS pop es assume es:code ;------------------------------------------------------------------------ ;Parse the command line for switches. ;------------------------------------------------------------------------ mov si,offset command_tail ;point SI to command line text xor cx,cx ;Clear high byte of CX add cl,[si] ;Get length of command line. jz parse_line_end ;If zero, skip parse routine inc si parse_line_loop: lodsb ;Get byte cmp al,'/' ;Look for command switch je parse_line_skip ;If found, process command loop parse_line_loop ;If not, keep looking jmp short parse_line_end parse_line_skip: lodsb ;Get command or al,20h ;Convert to lower case push cx mov di,offset commands ;Point to command letters mov cx,offset commands_end - offset commands mov bx,cx ;Save number of routines repne scasb ;Find command letter je command_found add sp,2 ;Clean up stack mov dx,offset errmsg1 ;Command not found msg jmp short disp_error command_found: sub bx,cx ;Compute offset into table pop cx ;Get back character count dec bx shl bx,1 ;Convert to word push es call [bx+offset jumptable] pop es jc disp_error ;Error if carry set. loop parse_line_loop parse_line_end: ;------------------------------------------------------------------------ ;Construct and print Accel key message ;------------------------------------------------------------------------ mov di,offset keytag mov es,other_seg mov al,es:shift_mask ;Get shift key mov ah,es:key_count ;Get key speed push ax ;Save key speed value push cs pop es mov bl,al ;See if specific to left mov cl,4 ; or right keys. shr bl,cl test al,8 je accel_0 or bl,4 accel_0: and al,07h cmp al,bl ;Compare left and right je accel_2 ; masks. mov si,offset left_tag ja accel_1 mov si,offset right_tag accel_1: call copy_str ;Copy Left/Right tag accel_2: or al,bl mov si,offset alt_tag test al,1 jne accel_3 mov si,offset ctrl_tag test al,2 jne accel_3 mov si,offset shift_tag accel_3: call copy_str pop ax ;Insert key speed value in add ah,30h ; message mov speedtag,ah mov ah,9 ;Print message mov dx,offset infomsg4 int 21h ;------------------------------------------------------------------------ ;See if installed. If not, install. ;------------------------------------------------------------------------ cmp alrdy_installed,0 ;If not installed, install je install mov ax,4c00h ;Else, terminate with RC = 0. int 21h ;------------------------------------------------------------------------ ;Display error message and exit with Return Code = 1. ;------------------------------------------------------------------------ disp_error: mov ah,9 ;Print string int 21h mov dx,offset end_msg mov ah,9 ;Print CR,LF int 21h mov ax,4c01h ;Exit RC = 1 int 21h ;------------------------------------------------------------------------ ;Install. Revector interrupts, Terminate and Stay Resident. ;------------------------------------------------------------------------ install: mov ax,cs ;Copy code segment mov word ptr [scanlist_ptr+2],ax ;Load segment into ptr mov ax,3508h ;Set interrupt 8 (timer) int 21h ; to the internal handler. mov word ptr [int8h],bx mov word ptr [int8h+2],es mov ax,2508h mov dx,offset timerint int 21h mov ax,3509h ;Set interrupt 9 (keyboard) int 21h ; to the internal handler. mov word ptr [int9h],bx mov word ptr [int9h+2],es mov ax,2509h mov dx,offset keybint int 21h mov dx,offset infomsg3 ;Say program installed. mov ah,9h int 21h mov dx,offset end_of_code ;Get pointer to the end of add dx,15 ; code. mov cl,4 shr dx,cl ;Convert to paragraphs mov ax,3100h ;terminate with ERRORLEVEL = 0 int 21h ;Return to DOS. initialize endp ;------------------------------------------------------------------------ ; ENABLE activates the cursor speedup feature. ;------------------------------------------------------------------------ enable proc near assume cs:code,ds:code mov es,other_seg ;point to installed segment mov es:enable_flag,1 ;Set enable flag clc ret enable endp ;------------------------------------------------------------------------ ; DISABLE deactivates the cursor speedup feature. ;------------------------------------------------------------------------ disable proc near assume cs:code,ds:code mov es,other_seg ;point to installed segment mov es:enable_flag,0 ;Clear enable flag clc ret disable endp ;------------------------------------------------------------------------ ; SPEEDSET sets the number of keys pushed into the buffer per timer int ;------------------------------------------------------------------------ speedset proc near assume cs:code,ds:code speedset_loop: jcxz speedset_err ;If EOL, error. lodsb dec cx cmp al," " jbe speedset_loop sub al,30h ;Convert to hex jbe speedset_err cmp al,9 ja speedset_err mov es,other_seg ;Get seg of installed code mov es:key_count,al ;Set count clc speedset_exit: ret speedset_err: mov dx,offset errmsg5 ;Bad key speed message stc jmp short speedset_exit speedset endp ;------------------------------------------------------------------------ ; KEYSET sets the shift key for acceleration of the cursor. ;------------------------------------------------------------------------ keyset proc near assume cs:code,ds:code mov dx,003fh ;Use DX as shift bit mask keyset_loop: mov al,[si] ;Get byte cmp al,'/' ;If next switch, end. je keyset_end inc si cmp al,' ' ;Check for a space. jb keyset_end ;If non character, exit ja keyset0 ;If not a space, process. loop keyset_loop ;If at the end of the command jmp short keyset5 ; line, end. keyset0: or al,20h ;Convert to lower case mov di,offset shiftkeys ;Point to command letters push cx ;Save command line count mov cx,offset shiftkeys_end - offset shiftkeys mov bx,cx ;Save number of keys repne scasb ;Find shift key letter je shiftkey_found ;If found, continue. add sp,2 ;If not, Clean up stack. mov dx,offset errmsg3 ;Not a proper shift key msg stc ;Set carry and exit. jmp short keyset_exit shiftkey_found: sub bx,cx ;Create index into keylist dec bx ;Check for left and right cmp bl,1 ;qualifiers, if so fix mask. ja keyset2 ;Not left or right, continue jb keyset1 ;Check for left qualifier and dl,38h ;Right qualifier, Clear off jmp short keyset4 ; left shift bits. keyset1: and dl,07h ;Left qualifier, Clear off jmp short keyset4 ; right shift bits. keyset2: mov cl,bl ;Shift bits by the index into sub cl,2 ; list of keys. This creates mov bl,11h ; a mask compatible with the shl bl,cl ; shift mask used in the int cmp bl,44h ; routine. jne keyset3 ;Fix mask if shift key mov bl,0ch keyset3: and bl,dl ;Clear off bits for L/R or dh,bl ;Add to shift mask mov dl,3fh ;Reset left/right mask keyset4: pop cx ;Restore command line counter loop keyset_loop ;Loop if not EOL keyset5: inc cx ;Fool loop instruction on ret keyset_end: or dh,dh ;Check for nul shift mask jne keyset6 ;If zero, set unshiftable bit mov dh,80h ; to disable. keyset6: mov es,other_seg ;point to installed segment mov es:shift_mask,dh ;Set new shift mask clc keyset_exit: ret keyset endp ;------------------------------------------------------------------------ ; DISPLAY HELP prints help message without installing. ;------------------------------------------------------------------------ display_help proc near mov dx,offset infomsg1 ;point to help text. stc ;Set flag to print message. ret display_help endp ;------------------------------------------------------------------------ ; UNINSTALL deallocates the memory block ownded by the program and ; restores the interrupt vectors displaced on installation. ;------------------------------------------------------------------------ uninstall proc near assume cs:code,ds:code push cx ;Save command line count cmp alrdy_installed,0 ;If not installed, don't jne uninstall0 ; remove. mov dx,offset errmsg4 ;Not installed msg jmp short uninstall_exit uninstall0: mov cx,other_seg ;Get segment of installed prog ; ;Make sure the timer and keyboard vectors has not been altered. ; mov ax,3508h ;check interrupt 8h vector int 21h mov ax,es cmp cx,ax ;transfer segment to AX jne uninstall_error mov ax,3509h ;check interrupt 9h vector int 21h mov ax,es cmp cx,ax ;transfer segment to AX jne uninstall_error ; ;Restore interrupt 8 and 9 vectors. ; mov es,cx ;Copy installed segment push ds ;save DS assume ds:nothing lds dx,es:[int8h] mov ax,2508h ;restore interrupt 8h vector int 21h lds dx,es:[int9h] mov ax,2509h ;restore interrupt 9h vector int 21h pop ds ;restore DS assume ds:code ; ;Release the memory occupied by the program. ; mov ah,49h ;Free memory given to int 21h ; original program block jc uninstall_error ;jmp if error cmp es:environment_flg,0 ;See if environment still je uninstall1 ; owned by resident code. push es mov es,es:env_seg ;Get segment of environment mov ah,49h ;Deallocate environment seg int 21h pop es jc uninstall_error ;Jmp if error uninstall1: ; ;Destroy the ASCII fingerprint that identifies the code and exit. ; not word ptr es:[begin] ;destroy fingerprint mov dx,offset infomsg2 ;Say program removed. uninstall_exit: stc ;Set flag to end program pop cx ret ;exit ; ;The program can't be uninstalled. Point to error message and exit. ; uninstall_error: mov dx,offset errmsg2 ;Remove error message jmp short uninstall_exit uninstall endp ;------------------------------------------------------------------------ ; CHECKVECTOR is called by REMOVE to compare the segment pointed to by an ; interrupt vector against a segment value supplied by the caller. ; Entry: AL - interrupt number ; Exit: ZF clear - segments do not match ; ZF set - segments match ;------------------------------------------------------------------------ checkvector proc near push es pop cx mov ah,35h ;get vector int 21h mov ax,es ;transfer segment to AX cmp ax,cx ;compare ret checkvector endp ;------------------------------------------------------------------------ ; COPYSTR Copies an ASCIIZ string ; Entry: SI - Ptr to source ASCIIZ string ; DI - Ptr to destination buffer ;------------------------------------------------------------------------ copy_str proc near push ax copy_str_1: lodsb or al,al je copy_str_2 stosb jmp short copy_str_1 copy_str_2: pop ax ret copy_str endp code ends end begin