changed VECTOR temporary storage address

c64/aliases/,aliases_ram_lowmem.s

@@ -45,6 +45,7 @@
 	.alias FNADDR     $BB ; $BB-$BC, current file name pointer
 
 	.alias STAL       $C1 ; $C1-$C2 LOAD/SAVE start address
+	.alias MEMUS      $C3 ; $C3-$C4 temporary address for tape LOAD/SAVE
 
 	;;
 	;; Other low memory addresses

c64/kernal/vector.s

@@ -20,8 +20,10 @@ vector:
 
 .scope
 
-	;; Temporary storage location
+	;; Temporary storage location - checked on real C64 that this is the
-	.alias _caller_arr_ptr CMP0
+	;; address originally used; after calling VECTOR and checking zero page
+	;; area afterwards, the address could be found there
+	.alias _caller_arr_ptr MEMUS
 
 	;; According to 'Compute's Mapping the Commodore 64' page 237,
 	;; the CBM implementation does not disable IRQs - yet, the
@@ -32,9 +34,10 @@ vector:
 	php
 	cli
 	
-	;; Prepare the user data pointer
+	;; Prepare the user data pointer - strange order to reduce risk
-	stx _caller_arr_ptr + 0
+	;; of potential similarity to the original routine
 	sty _caller_arr_ptr + 1
+	stx _caller_arr_ptr + 0
 	
 	;; Select routine variant - store or restore vectors
 	ldy #$1F