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Analogy:
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(The other device that can perform read/write operations is the DMA (Direct Memory Access) - you will learn about this in CS355.
In CS255, the only device that performs read/write operation will be the CPU.)
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Questions:
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The address will specify which memory cells the requested operation will be performed !!!
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Each (electrical) wire in the buses can carry a electrical signal that can be:
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The CPU will use high/low voltage signals conveyed through the wires to specify what operation that the CPU wants to perform !!!
(Each wire in the control bus is associated with a specific operation (= command))
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I will give a little more detail on how the CPU reads/writes data from/to memory to help you understand the operation of the computer.
For a full discussion, you will need to take CS355....
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These steps (= events) must proceed in the above order and it is called a read protocol
For a detail discussion of the memory read protocol, you must take CS355
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The CPU transfer data from itself (= CPU) to the memory as follows:
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These steps (= events) must also proceed in the above order and it is called a write protocol
Also, for a detail discussion of the memory write protocol, you must take CS355
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In CS170 and CS171, you have learned that variables can be organized into (different kinds of) data structures:
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