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I am trying to point out that you do not abbreviate a microprocessor as MPU but as CPU. MPU is solely reserved for Memory Protection Unit and it might confuse some people.
Source: https://en.wikipedia.org/wiki/Microprocessor, http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.ddi0337e/BIHJJABA.html

Now I get you. That's what I just learned from my teacher though! anyway, thanks for commenting

I'm sorry. I didn't make it clear enough.