XREF	MYRAM
	XREF  CNTVAL
	XREF  CNTVAL1
	XREF	COUNTREG
	XDEF	CAL_CHKSUM
CAL_CHKSUM
	LDAA	 #CNTVAL		
	STAA	 COUNTREG	
	LDX	 #MYRAM	
	CLRA			
B2	ADDA	 1,X+ 	
	DEC	 COUNTREG	
	BNE 	 B2		
	NEGA			
	STAA	0,X		
	RTS			
	END