2. I/O

The memory locations accessible by a computer system's processor are determined by their address within the processor's address space. Some processors, such as the Intel 8085, have a memory address space and an I/O address space. Other processors, such as the 68000 processor, have only one common address space for memory and I/O. In this case, a specific memory-mapped input-output space is associated with the memory address space.

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