I am totally panicking - I just realised that I don't even know what the fetch execute cycle is. I would appreciate it so much if someone just went through it for me, like mentioning all the important buses? sorry. you know what us girls are like - don't know anything about computers. JOKING!
Sorry I hated the Fetch Execute Cycle so really in the exam I just remembered all the steps! It's also been a year since I done it.
From Scholar: -
1. The contents of the PC are copied into the MAR; 2. The contents of memory at the location designated by the MAR are copied into the MDR; 3. The PC is incremented; 4. The contents of the MDR are copied into the IR. 5. Decode the instruction in the IR; 6. Execute the instruction in the IR.
The First Part is the Fetch the Second the Execute.
I really can't go into much detail but I can't remember if you need to remember the lines and stuff but I have a funny feeling you do. It would be good to atleast just even learn the steps because your going to be asked about it.
Also a Key to the Quote
PC - Program Counter MAR - Memory Address Register MDR - Memory Data Register IR - Instruction Register
Fetch: This part of the cycle reads the next instruction from main memory into the processor; 1. The memory address of the next instruction is placed on the address bus. 2. A read signal is activated on the control line. 3. The data stored at the addressed memory location is placed on the data bus and transferred to a register which holds it until it is executed.
Execute: 4. The processor interprets the instruction. 5. The processor carries out the instruction.