Fetch Decode Execute Cycle

Fetch Decode Execute Cycle

Fetch Transfer Notation

[PC] -> MAR

[Memory] -> MBR

[PC] + 1 -> PC

[MBR] -> CIR

Explanation

The address of the next instruction to be executed is copied from the Program Counter to the Memory Address Register.

The instruction at that address is then copied to the Memory Buffer Register.

Simultaneously, the contents of the Program Counter are incremented by 1.

The contents of the Memory Buffer Register are copied to the Current Instruction Register.

Decode Transfer Notation

[CIRop-code] → CU

Explanation

The op code from the CIR is passed to the Control Unit