Add blinking cursor on input

git-svn-id: svn://svn.cc65.org/cc65/trunk@944 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/cbm510/Makefile

@@ -21,6 +21,7 @@ OBJS =	_scrsize.o	\
 	cputc.o		\
        	crt0.o 	 	\
        	kbhit.o	 	\
+	kblncur.o	\
        	kirq.o 	 	\
        	kplot.o	 	\
 	kscnkey.o	\

libsrc/cbm510/cgetc.s

@@ -1,11 +1,10 @@
 ;
-; Ullrich von Bassewitz, 06.08.1998
+; Ullrich von Bassewitz, 16.09.2001
 ;
 ; char cgetc (void);
 ;
 
 	.export	   	_cgetc
-	.import	   	plot, write_crtc
 	.import	   	cursor
 
 	.include   	"zeropage.inc"
@@ -16,23 +15,81 @@
 
 .proc	_cgetc
 
-L1:    	lda	KeyIndex
+    	lda	KeyIndex		; Characters waiting?
-       	beq	L1
+       	bne    	L3			; Jump if so
 
-L2:    	ldx    	#$00		; Get index
+; Switch on the cursor if needed
-       	ldy	KeyBuf		; Get first character in the buffer
+
-       	sei
+  	lda	CURS_FLAG
-L3:    	lda	KeyBuf+1,x	; Move up the remaining chars
+  	pha
-       	sta	KeyBuf,x
+  	lda	cursor
+  	jsr	setcursor
+L1:	lda	KeyIndex
+  	beq	L1
+  	ldx	#0
+    	pla
+ 	bne	L2
        	inx
-       	cpx	KeyIndex
+L2:    	txa
-       	bne	L3
+       	jsr	setcursor
-       	dec	KeyIndex
+
+; Read the character from the keyboard buffer
+
+L3:    	ldx    	#$00		; Get index
+       	ldy    	KeyBuf		; Get first character in the buffer
+       	sei
+L4:    	lda    	KeyBuf+1,x	; Move up the remaining chars
+       	sta    	KeyBuf,x
+       	inx
+       	cpx    	KeyIndex
+       	bne    	L4
+       	dec    	KeyIndex
        	cli
 
-       	ldx	#$00		; High byte
+       	ldx    	#$00		; High byte
-       	tya			; First char from buffer
+       	tya    			; First char from buffer
        	rts
 
 .endproc
 
+; ------------------------------------------------------------------------
+;
+
+.proc	setcursor
+
+	ldy	#$00		       	;
+       	tax			       	; On or off?
+       	bne    	@L9		       	; Go set it on
+    	lda	CURS_FLAG	       	; Is the cursor currently off?
+       	bne    	@L8			; Jump if yes
+    	lda	#1
+    	sta	CURS_FLAG		; Mark it as off
+    	lda	CURS_STATE		; Cursor currently displayed?
+	sty	CURS_STATE		; Cursor will be cleared later
+       	beq    	@L8			; Jump if no
+
+; Switch to the system bank, load Y with the cursor X coordinate
+
+	lda	#$0F
+	sta	IndReg	   	       	; Access system bank
+	ldy	CURS_X
+
+; Reset the current cursor
+
+     	lda    	CURS_COLOR
+	sta	(CRAM_PTR),y	       	; Store cursor color
+      	lda	ExecReg
+      	sta	IndReg 		       	; Switch to our segment
+      	lda	(SCREEN_PTR),y
+      	eor	#$80	      	       	; Toggle reverse flag
+      	sta	(SCREEN_PTR),y
+
+; Done
+
+@L8:  	rts
+
+@L9: 	sty	CURS_FLAG	       	; Cursor on (Y = 0)
+	rts
+
+.endproc
+

libsrc/cbm510/kblncur.s

@@ -0,0 +1,56 @@
+;
+; Ullrich von Bassewitz, 16.09.2001
+;
+
+	.export		k_blncur
+
+	.include   	"zeropage.inc"
+
+
+; ------------------------------------------------------------------------
+; Blink the cursor in the interrupt
+
+.proc   k_blncur
+
+        lda     CURS_FLAG		; Is the cursor on?
+        bne     curend			; Jump if not
+        dec     CURS_BLINK
+        bne     curend
+
+; Re-initialize the blink counter
+
+        lda     #20	  	 	; Initial value
+        sta     CURS_BLINK
+
+; Switch to the system bank, load Y with the cursor X coordinate
+
+      	lda	#$0F
+      	sta	IndReg	   	       	; Access system bank
+      	ldy	CURS_X
+
+; Check if the cursor state was on or off before
+
+      	lda	CURS_COLOR	       	; Load color behind cursor
+      	lsr	CURS_STATE	       	; Cursor currently displayed?
+      	bcs    	curset		       	; Jump if yes
+
+; Cursor was off before, switch it on
+
+      	inc	CURS_STATE	       	; Mark as displayed
+      	lda	(CRAM_PTR),y	       	; Get color behind cursor...
+      	sta	CURS_COLOR	       	; ...and remember it
+      	lda	CHARCOLOR	       	; Use character color
+
+; Set the cursor with color in A
+
+curset:	sta	(CRAM_PTR),y	       	; Store cursor color
+      	lda	ExecReg
+      	sta	IndReg 		       	; Switch to our segment
+      	lda	(SCREEN_PTR),y
+      	eor	#$80	      	       	; Toggle reverse flag
+      	sta	(SCREEN_PTR),y
+curend:	rts
+
+.endproc
+
+

libsrc/cbm510/kirq.s

@@ -5,7 +5,7 @@
 ;
 
  	.export	  	irq, nmi, k_irq, k_nmi
- 	.import		k_scnkey, k_udtim, k_rs232
+ 	.import		k_blncur, k_scnkey, k_udtim, k_rs232
  	.importzp     	tpi1
 
  	.include      	"zeropage.inc"
@@ -72,6 +72,7 @@ k_irq:
 
 	cmp	#%00000001		; ticker irq?
 	bne	irq1
+	jsr	k_blncur		; Blink the cursor
 	jsr     k_scnkey		; Poll the keyboard
         jsr	k_udtim			; Bump the time
 

libsrc/cbm510/zeropage.inc

@@ -93,13 +93,13 @@ ScreenRight    	= $DF
 ModKey 	       	= $E0
 NorKey 	       	= $E1
 BitTable       	= $E2
-BlinkOn		= $E6
+CURS_FLAG	= $E6		; 1 = no cursor
-BlinkCounter	= $E7
+CURS_BLINK	= $E7		; cursor blink counter
 CRAM_PTR	= $E8
 TempColor	= $EA
-BlinkSwitch	= $EB
+CURS_STATE	= $EB		; Cursor blink state
 CHARCOLOR	= $EC
-CursBackColor	= $ED		; Color behind cursor
+CURS_COLOR	= $ED		; Color behind cursor
 OutCharTmp	= $EE
 ScreenSeq	= $EF		; Segment of video RAM