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Fetch-Decode-Execute Cycle (FDE) is the basic operational process of a computer. it is the process where the computer receives a program instruction from its memory, determines what actions to take, and carries out those actions.

Von Neuman vs Harvard architecture:

Von Neuman has a single storage system(memory) for storing data as well as programs to be executed. it has a single set of address/data buses between CPU and memory. the processor needs clock cycles to complete an instruction. this is an outdated method and is replaced by Harvard.

Harvard has 2 separate memories for storing data and programs. two sets of address/data buses for CPU and memory. the processor only takes 1 clock cycle to complete an instruction. pipelining is implemented.

Interrupts work by, if an interrupt has a higher priority over what is happening in the CPU, then the current FDE cycle will finish and it will carry out that instruction instead but if it is a lower priority then it will be placed at the back of the queue for the CPU to execute later.

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