Category : Dbase (Clipper, FoxBase, etc) Languages Source Code
Archive   : ASMFILE.ZIP
Filename : CURSOR.ASM

;
;****************************************************************
; *
; CLIPPER ROUTINE - CURSOR ON / OFF ( IBM PC ONLY ) *
; By Kelly Mc Tiernan *
; *
;****************************************************************
;
;
; This routine is called to turn the cursor on and off.
; It is a toggle i.e. - call to turn off, upon next call,
; cursor is turned on.
;
; CALL CURSW
; * Do video i/o
; CALL CURSW
; * Get input
;
; Also provides for manual over - ride via WITH ->
;
; CALL CURSW WITH "ON"
; CALL CURSW WITH "OFF"
;
; *** NOTE: COMMAND MUST BE CAPS ! ***
;
PUBLIC cursw
;
video EQU 10h ; ROM BIOS video interupt
curlin EQU 01h ; Set cursor lines function
offlin EQU 0FF00h ; Works with MOST PC compatables !
colcur EQU 0A0Bh ; " " " " " " " !
eqpchk EQU 11h ; equipment check interupt
off EQU 0FFh ; Flag test value, cursor off ?
on EQU 00h ; Flag for cursor on.
bw EQU 30h ; bits indicate B/W card.
;

_PROG SEGMENT BYTE
ASSUME CS:_PROG
;
cursw PROC FAR
push bp ; standard setup, param's
mov bp,sp ;
push ds ; save, need for string compare
push es ; " , " " " " "
cld ; assure proper direction for cmpsb
cmp byte ptr cs:[fstpas],0 ; check display type on first pass
jnz docurs ; set start/stop line on first
mov byte ptr cs:[fstpas],1 ; to skip this after first time
int eqpchk ; check if color / mono board
and ax,bw ; black and white ?
cmp ax,bw ;
jnz docurs ; color, leave as 0707h
mov word ptr cs:[onlin],colcur
docurs:
mov ah,curlin ; set up for cursor on/off function
lds si,dword ptr [bp + 6] ; address of command param. if inc.
mov bx,si ; save for "OFF" command check
push cs ; get segment
pop es ; for compare
mov di,offset cs:oncmd ; get offset for compare
mov cx,3 ; length of on command
rep cmpsb ; compare string - WITH "ON" ?
jnz offtst ; not "ON" command, check for "OFF"
mov byte ptr cs:[curflg],off ; set flag accordingly
mov cx,cs:[onlin] ; turn it on
jmp short curon ; ( save a byte )
offtst:
mov si,bx ; get back param. ptr.
mov di,offset cs:offcmd ; and table ptr.
mov cx,4 ; length of "OFF" string
rep cmpsb ; compare string - WITH "OFF"
jnz switch ; no over - ride, do toggle
mov byte ptr cs:[curflg],on ; set flag
mov cx,offlin ; turn it off
jmp short curon ;
switch:
mov cx,cs:[onlin] ; default is turn off, is it off ?
cmp byte ptr cs:[curflg],off
jz curon ; yes, turn it on
mov cx,offlin ; change up
curon:
int video ; set cursor lines
not byte ptr cs:[curflg] ; flip switch flag
pop es ; restore state, normalize stack
pop ds ;
pop bp ;
ret
cursw ENDP
;
curflg DB 00h ; ON / OFF FLAG - INIT. SET TO ON
fstpas DB 00h ; for equip check on first pass
oncmd DB 'ON',0 ; WITH PARAM - ON COMMAND
offcmd DB 'OFF',0 ; " " - OFF COMMAND
onlin DW 0707h ; default cursor ( COLOR / MONO )
;
_PROG ENDS
END