AppleIIAsm-Collection/disks/disk1__stdio/T.STDIO.TVLIN

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*
*``````````````````````````````*
* TVLIN :: TEXT VERTICAL LINE *
*- -*
* CREATES A VERTICAL LINE OF *
* TEXT COMPOSED OF THE FILL *
* CHARACTER SPECIFIED AT X. *
*- -*
* CLOBBERS: *
* *
* FLAGS: ????---- REG: AXYM *
*- -*
* CYCLES: ??? *
* SIZE: *
*- -*
* USAGE: *
* LDA (Y-START) *
* PHA *
* LDA (Y-END) *
* PHA *
* LDA (X-POS) *
* PHA *
* LDA (FILL CHAR) *
* PHA *
* JSR TVLIN *
*- -*
* ENTRY *
* *
* TOP OF STACK *
* *
* LOW BYTE OF RETURN ADDRESS *
* HI BYTE OF RETURN ADDRESS *
* XPOS START OF LINE (:Y1) *
* XPOS END OF LINE (:Y2) *
* YPOS OF LINE (:X) *
* FILL CHARACTER (:F) *
*- -*
* EXIT *
* *
* TOP OF STACK *
* *
* LOW BYTE OF RETURN ADDRESS *
* HI BYTE OF RETURN ADDRESS *
* *
* Y = END OF LINE *
* X = HORIZONTAL POSITION *
* A = LOW BYTE OF RET ADDR *
*,,,,,,,,,,,,,,,,,,,,,,,,,,,,,,*
*
TVLIN
*
** SAVE RETURN ADDRESS
*
PLA
STA :RETADR
PLA
STA :RETADR+1
*
** GET PARAMETERS
*
PLA
STA :F ; FILL CHAR
PLA
STA :X ; X POS
PLA
STA :Y2 ; END
PLA
STA :Y1 ; START
*
LDX :X
LDY :Y1
STY CURSV
STX CURSH
JSR VTAB ; SET CURSOR POS
:LOOP
JSR COUT1 ; PRINT CHAR
LDX :X
STX CURSH
STY CURSV
JSR VTAB ; SET NEW CURSOR POS
LDA :F ; RELOAD FILL CHAR
INY ; INCREASE COUNTER
CPY :Y2 ; IF Y1 < Y2
BNE :LOOP ; LOOP; ELSE, CONTINUE
:EXIT
*
** RESTORE RETURN ADDRESS
*
LDA :RETADR+1
PHA
LDA :RETADR
PHA
*
RTS
*
** DATA
*
:RETADR DS 2
:X DS 1
:Y1 DS 1
:Y2 DS 1
:F DS 1