Memory packed Sieve of Atkin WIP

Instead of saving every number in Sieve of Atkin in single memory cell
(16bit) saving 16 numbers in very number. Missing modification to print
function.

memory/risc8.asm

@@ -587,23 +587,55 @@ sieveOfAtkinInvN
 	PUSH r0
 	PUSH r1
 	PUSH r3
+	PUSH r2
+	
+	CPY3 16
+	DIV r2,r3; n/=16
+
 	CPY0 MEMEND@0
 	CPY1 MEMEND@1
-	ADD r0,r2
+	ADD r0,r2 ; add n to pointer
 	ADDC r1
+
+	CI0 r0
+	CI1 r1
+	LWHI r2,NULL
 	CI0 r0
 	CI1 r1
 	LWLO r3,NULL
-	XORI r3,1
+	PUSH r0
+	PUSH r1
+	; check if high or low byte
+	; n is saved from MSB to LSB e.g.:
+	; data in memory address:
+	;    0 0 0 0  0 0 0 0    0 0 0 0  0 0 0 0
+	; n= 0 1 2 3  4 5 6 7    8 9 A B  C D E F
+	; At this point r3=memLO, r2=memHI
+	CPY0 1
+	AH r1; n%16
+	BGE r1,8,.lo
+	JUMP .hi
+.lo
+	SUBI r1,8
+	CI2 r1
+	SLL r0,0  ; 1 << (n-8)
+	XOR r3,r0
+	JUMP .fi
+.hi
+	CI2 r1
+	SLL r0,0  ; 1 << n
+	XOR r2,r0
+.fi
+	; Everything's been flipped, time to upload to ram
+	POP r1
+	POP r0
+
+	SWHI r2
 	CI0 r0
 	CI1 r1
 	SWLO r3,NULL
-
-	MOVE r0,r2
-	CALL printU8
-	CPY0 0x20
-	CALL print_char
-
+	
+	POP r2
 	POP r3
 	POP r1
 	POP r0