; This program calculates the sum of signed numbers

	AREA	PROG5_1,CODE,READONLY
	ENTRY
	
	LDR	R0,=SIGN_DAT
	MOV	R3,#9
	MOV	R2,#0
LOOP	LDRSB 	R1, [R0]  
	;Load into R1 and sign extend it.			
	ADD	R2,R2,R1	;R2 = R2 + R1
	ADD	R0,R0,#1	;point to next
	SUBS	R3,R3,#1	;decrement counter
	BNE	LOOP
	LDR 	R0,=SUM
	STR	R2,[R0]		;Store R2 in location SUM
HERE	B	HERE	

SIGN_DAT DCB 	+13,-10,+19,+14,-18,-9,+12,-19,+16

	AREA	VARIABLES,DATA,READWRITE
SUM	DCD	0
	END