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assemblycpu-architecture

What exactly this line means?

The location is the address of the memory word where the instruction is stored. It is important to differentiate it from the address part of the instruction itself

I am reading Morris Mano's book on computer system architecture and I am getting more and more confused whenever the word MEMORY comes up and now here I don't exactly understand the difference being talked about here in statement 2.

Solution

  • Let's suppose our hypothetical CPU has an instruction to load a register from an address in memory:

    LOAD R<n>,<address>

    Now let's suppose that your program contains an example of such an instruction, at address 0x1000, that loads register R3 from address 0x5678:

    00001000   LOAD R3,0x5678

    Then according to your quote, the location is 0x1000, and the address part of the instruction is 0x5678.