Contributed files from Oliver Schmidt

git-svn-id: svn://svn.cc65.org/cc65/trunk@2920 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/apple2enh/cputc.s

@@ -0,0 +1,100 @@
+;
+; Ullrich von Bassewitz, 06.08.1998
+;
+; void cputcxy (unsigned char x, unsigned char y, char c);
+; void cputc (char c);
+;
+
+	.constructor	initconio
+   	.export		_cputcxy, _cputc
+	.export		_gotoxy, cputdirect
+	.export		newline, putchar
+
+	.import		popa
+
+	.include	"../apple2/apple2.inc"
+
+
+initconio:
+	lda	#$FF		; Normal character display mode
+	sta	INVFLG
+	sta	SETALTCHAR	; Switch in alternate charset
+	rts
+
+; Plot a character - also used as internal function
+
+_cputcxy:
+	pha			; Save C
+	jsr	popa		; Get Y
+	jsr	_gotoxy
+	pla			; Restore C
+
+_cputc:
+	cmp	#$0D		; Test for \r = carrage return
+	bne	L1
+	stz	CH		; Goto left edge of screen
+	rts			; That's all we do
+L1:
+	cmp	#$0A		; Test for \n = line feed
+	beq	newline
+	ora	#$80		; Turn on high bit
+
+cputdirect:
+	jsr	putchar
+	inc	CH		; Bump to next column
+	lda	CH
+	cmp	WNDWDTH
+	bne	return
+	stz	CH
+return:
+	rts
+
+putchar:
+	ldy	INVFLG
+	cpy	#$FF		; Normal character display mode?
+	beq	put
+	cmp	#$E0		; Lowercase?
+	bmi	mask
+	and	#$7F		; Inverse lowercase
+	bra	put
+mask:
+	and	INVFLG		; Apply normal, inverse, flash
+put:
+	ldy	CH
+	bit	RD80VID 	; In 80 column mode?
+	bpl	col40		; No, in 40 cols
+	pha
+	tya
+	lsr			; Div by 2
+	tay
+	pla
+	bcs	col40		; Odd cols go in 40 col memory
+	bit	HISCR
+	sta	(BASL),Y
+	bit	LOWSCR
+	rts
+col40:
+	sta	(BASL),Y
+	rts
+
+newline:
+	lda	CH
+	pha
+	inc	CV
+	lda	CV
+	cmp	WNDBTM
+	bne	L2
+	lda	#$00
+	sta	CV
+L2:
+	jsr	VTABZ
+	pla
+	sta	CH
+	rts
+
+_gotoxy:
+	sta	CV		; Store Y
+	jsr	VTABZ
+	jsr	popa		; Get X
+	sta	CH		; Store X
+	rts