1. Then we examine the instruction cycle, the sequence of operations that occurs within the computer as it fetches, decodes , and executes an instruction.

2. At the beginning of each instruction cycle, the CPU fetches an instruction from memory.

3. The instruction cycle can be divided into ( fetch ) cycle and ( execution ) cycle.

4. In an SISD architecture there is a single instruction cycle; operands are fetched serially into a single processing unit before execution.

5. In those days, working with computers meant writing code to save a byte here and an instruction cycle there.

6. The use the single - chip reduced instruction set, instruction cycle clock are the number of CPU units.