7.6.2. Instruction Phases

Try these first

1. 1.

   What are the four phases of the instruction cycle?

   Hint

   Remember the acronym F-D-E-S.

2. 2.

   Define a macro instruction.

   Hint

   Think about how macro instructions differ from micro instructions.

3. 3.

   What are the four phases of the instruction cycle?

   • Fetch
   • Decode
   • Execute
   • Store
   • Read
   • Process
   • Store
   • Output
   • Fetch
   • Execute
   • Decode
   • Run

   Hint

   Remember the order of executing an instruction.

4. 4.

   True or False: Micro instructions require multiple clock cycles to execute.

   • True
   • False

   Hint

   Think about how micro instructions are defined.

5. 5.

   Describe a scenario where a macro instruction would require optimization using clock grouping. Provide details on the instructions involved.

   Hint

   Think of how two separate data movements can happen at the same time without conflict.

6. 6.

   Explain how complex macro instructions can impact CPU performance and how micro instructions can alleviate these issues.

   Hint

   Consider the time savings from separating complex tasks into smaller, manageable parts.