reduce byte-wise similarity with KERNAL through use of X instead of A

c64/kernal/chrout.s

@@ -68,14 +68,22 @@ no_need_to_extend:
 	jsr get_current_line_logical_length
 	tay
 *
-	dey
+	;; Note: While the following routine is obvious to any skilled
-	lda (current_screen_line_ptr),y
+	;; in the art as the most obvious simple and efficient solution,
-	iny
+	;; if the screen writes are before the colour writes, it results
-	sta (current_screen_line_ptr),y
+	;; in a relatively long verbatim stretch of bytes when compared to
+	;; the C64 KERNAL.  Thus we have swapped the order, just to reduce
+	;; the potential for any argument of copyright infringement, even
+	;; though we really don't believe that the routine can be copyrighted
+	;; due to the lack of creativity.
 	dey
 	lda (current_screen_line_colour_ptr),y
 	iny
 	sta (current_screen_line_colour_ptr),y
+	dey
+	lda (current_screen_line_ptr),y
+	iny
+	sta (current_screen_line_ptr),y
 
 	dey
 	cpy current_screen_x

c64/kernal/ramtas.s

@@ -40,17 +40,20 @@ ramtas_l2:
 	STA $DD00
 
 	;; Set screen address pointer ("Compute's Mapping the 64" p238)
-	LDA #>$0400
+	;; This is obvious boiler plate containing no creative input, but to avoid
-	STA HIBASE
+	;; unnecessarily similarity to the C64 KERNAL, we use X instead of A to do this,
+	;; and several following
+	LDX #>$0400
+	STX HIBASE
 	
 	;;  Work out RAM size and put in MEMSTR and MEMSIZ
 	;; "Compute's Mapping the 64", p54
 	;;  http://unusedino.de/ec64/technical/project64/mapping_c64.html
-	lda #>$0800
+	ldx #>$0800
-	sta MEMSTR+1
+	stx MEMSTR+1
-	lda #$00
+	ldx #$00
-	sta MEMSTR+0
+	stx MEMSTR+0
-	sta MEMSIZ+0
+	stx MEMSIZ+0
 	;; Try to modify $8000, if it fails then RAM ends at $7FFF, else $9FFF
 	lda $8000
 	eor #$FF
@@ -60,13 +63,13 @@ ramtas_l2:
 	cmp $8000
 	beq ramtas_32K_RAM
 	sta $8000
-	lda #$A0
+	ldx #$A0
-	sta MEMSIZ+1
+	stx MEMSIZ+1
 	jmp ramtas_RAM_sized
 ramtas_32K_RAM:	
 	sta $8000 		; in case RAM is hiding beneath a ROM
-	lda #$80
+	ldx #$80
-	sta MEMSIZ+1
+	stx MEMSIZ+1
 	;; Fall through
 ramtas_RAM_sized: