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Functions of CPU components
Three major components of a Central Processing Unit (CPU) are:
- control unit
- clock
- cache.
Describe the function of each of the three components.
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Marking points
- 1 For full credit, includes credited functions from all three named CPU components.
- 2 Decoding instructions is a credited control-unit function.
- 3 Coordinating instruction execution is a credited control-unit function.
- 4 Sending control signals/controlling flow is a credited control-unit function.
- 5 Coordinating I/O devices is a credited control-unit function.
- 6 Sending a regular pulse is a credited clock function.
- 7 Synchronising operations is a credited clock function.
- 8 Influencing instructions per second is a credited clock function.
- 9 More efficient memory retrieval is a credited cache function.
- 10 Storing data/instructions for faster access is a credited cache function.
- 11 Storing frequently/soon-used data or instructions is a credited cache function.
Full-mark answer
Control unit: it decodes instructions and sends control signals to coordinate their execution. Clock: it sends regular electrical pulses that synchronise CPU operations. Cache: it stores frequently used data and instructions close to the processor so they can be accessed more quickly.
Why this answer loses marks
The control unit controls things, the clock tells the time, and cache stores files.
Each component needs its CPU function: instruction control, synchronising pulses, or fast access to likely data and instructions.