Microprocessor Design/Memory Unit
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Microprocessors rely on memory for storing the instructions and the data used by software programs. The memory unit is responsible for communicating with the system memory.
[edit] Memory Unit
[edit] Actions of the Memory Unit
In a harvard architecture, the data memory unit and the instruction memory unit are the same. However, in a non-Harvard architecture the two memory units are combined into a single module. Most modern PC computer systems are not Harvard, so the memory unit must handle all instruction and data transactions. This can serve as a bottleneck in the design.
[edit] Timing Issues
The memory unit is typically one of the slowest components of a microcontroller, because the external interface with RAM is typically much slower then the speed of the processor.