Gerry, 11 Aug you wrote to me:
[volatile]
 GD> I don't understand why all screen output would be removed
 GD> due to optimization.  Can you explain, please?
Jeery and Anthony already explained it.
Since you don't tell the compiler another process will be influenced by 
writing to that memory. Your program isn't reading that memory, and unless 
you tell the compiler some other process uses the memory, it _may_ assume it 
is unnecessary to perform the writes, if it is a good optimizer it will of 
course do that, reducing code size _and_ increasing speed.
Bye,
 Erik 
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