;
; UFRGS - INF - M Johann - 2023 - johann@inf.ufrgs.br
; Writes first 14 numbers of the Fibonacci sequence:
; 0,1,1,2,3,5,8,13,21,34,55,89,144,233


; ----- DATA 

		org	h80
screen:		dab	0,1,0,0,0,0,0,0,0,0,0,0,0,0

		
; ----- BEGIN MAIN CODE 

		org	0
startup:	LDR	X,#screen+#1	; index at second position
		LDR	A,screen+1	; first = sum in RA
		LDR	B,#12		; RB controls iterations

loop:		ADD	A,-1,X		; adds previous position
		STR	A,1,X		; stores at next position
		ADD	X,#1		; advance position
		SUB	B,#1		; decrement loop
		JZ 	finish	
		JMP 	loop

finish:		HLT
		
; END OF FILE