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Setting up a 'global variable' using DCD

Question asked by o.l.001 on Mar 26, 2014
Latest reply on Mar 26, 2014 by o.l.001
I have a jump table currently set-up like this
ProcTable
 DCD Proc1
 DCD Proc2
 DCD Proc3
EndTable

Another part of my program that is acting as a processes manager which needs to keep track of the number of the process so it can calculate a stack pointer (PSP) for it so that each program has it's only section of the stack. I'm trying to use some sort of 'global variable' like this 
"ProcCount DCD 0" 
I then want to increment the value stored in ProcCount although I'm having trouble getting this to work, most examples I can find involve reading the value of ProcCount but never writing/updating the other way. I was trying to do something like this:

 LDR r2,=ProcCount
 ADD r4,r4,#1
 STR r4, [r2]
 NOP
 LDR r5,ProcCount
 NOP

I'm trying to add #1 to ProcCount then reading it back into r5 to check that it has changed (Nothing changes r5 stays at 0x0)


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