Make screensize() fetch the values dynamically instead of using variables

that are set on startup. This is needed to support the C128, which can switch
the screen size at runtime.


git-svn-id: svn://svn.cc65.org/cc65/trunk@2042 b7a2c559-68d2-44c3-8de9-860c34a00d81

libsrc/conio/scrsize.s

@@ -6,24 +6,29 @@
 
     	.export	 	_screensize
 
-	.import	 	popax
-	.import		xsize, ysize
-	.importzp	ptr1, ptr2
+	.import	       	popsreg
+	.import	       	screensize
+	.importzp      	ptr1, sreg
 
 .proc	_screensize
 
-	sta	ptr1		; Store the y pointer
+	sta	ptr1   	       	; Store the y pointer
 	stx	ptr1+1
+        jsr     popsreg         ; Get the x pointer into sreg
+        jsr     screensize      ; Get screensize into X/Y
+        tya                     ; Get Y size into A
 
-	jsr	popax		; get the x pointer
-	sta	ptr2
-	stx	ptr2+1
+.IFP02
+      	ldy	#0
+        sta     (ptr1),y
+        txa
+        sta     (sreg),y
+.ELSE
+        sta     (ptr1)
+        txa
+        sta     (sreg)
+.ENDIF
 
-	ldy	#0
-	lda	xsize
-	sta	(ptr2),y
-	lda	ysize
-	sta	(ptr1),y
    	rts
 
 .endproc