I'm a really beginner with ARM. I write a very simple program to find the sum of three values Q,R,S and store it in the memory. However it doesn't works. Someone can show me what is my mistake. Thanks for your help.
AREA Example3, CODE, READONLY
EXPORT SystemInit
EXPORT __main
ENTRY
SystemInit
__main
LDR R1,Q ;load r1 with Q
LDR r2,R ;load r2 with R
LDR r3,S ;load r3 with S
ADD r0,r1,r2;add Q to R
ADD r0,r3;add in S
LDR r4,=Q
STR r0,[R4] ;store result in Q
;Stop B Stop
P SPACE 4 ;save one word of storage
Q DCD 2 ;create variable Q with initial value 2
R DCD 4
S DCD 5
END