The cycle required to fetch and execute an instruction in an 8085 microprocessor is known as a __________.

The correct answer is: Instruction cycle

Explanation:

In the context of an 8085 microprocessor (or any microprocessor), the process required to fetch and execute an instruction is known as the "Instruction Cycle". This cycle consists of the following steps:

• Fetch the instruction: The instruction to be executed is retrieved from memory.
• Decode the instruction: The CPU interprets the instruction and determines what actions to perform.
• Execute the instruction: The CPU performs the required operations.
• An instruction cycle can be composed of multiple machine cycles (like fetching from memory and executing the instruction), and each machine cycle can be composed of multiple T-states or clock cycles.

1) Machine cycle: This refers to the basic operation performed by the microprocessor, such as reading data from memory, writing data to memory, or interacting with an external device. Fetching and executing an instruction can involve multiple machine cycles.

2) Memory cycle: This term is less commonly used, but if used, it could potentially represent the cycle time for operations involving the memory, such as read or write operations.

3) Clock cycle: This is the time interval during which one full operation of the system clock occurs. It is the smallest unit of time recognized by the microprocessor. Many clock cycles may be required to perform a single machine cycle, which in turn may require multiple machine cycles to perform an instruction cycle.