Added condes IRQ routines and a README file.

Made k_blncur a condes IRQ routine and moved it to cgetc.s.
Added mouse and joystick routines.


git-svn-id: svn://svn.cc65.org/cc65/trunk@951 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/cbm510/cgetc.s

@@ -5,6 +5,7 @@
 ;
 
 	.export	   	_cgetc
+	.condes		k_blncur, 2
 	.import	   	cursor
 
 	.include   	"zeropage.inc"
@@ -90,6 +91,61 @@ L4:    	lda    	KeyBuf+1,x	; Move up the remaining chars
 
 @L9: 	sty	CURS_FLAG	       	; Cursor on (Y = 0)
 	rts
+				   
+.endproc
+
+
+; ------------------------------------------------------------------------
+; Blink the cursor in the interrupt. A blinking cursor is only available if
+; we use the cgetc() function, so we will export this IRQ handler only in
+; case the module is included into a program.
+
+
+.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
+
+; Load Y with the cursor X coordinate
+
+      	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
+
+; Switch back to the system bank
+
+      	lda	#$0F
+      	sta	IndReg
+
+curend:	rts
 
 .endproc
 
+