GCSE J277 - 1.1.1 - Systems Architecture

Manages basic operations of the computer. To be the ‘brains’ of the computer

• CPU
• RAM
• ROM
• Motherboard

A register which keeps the address of the next instruction to be processed

• MAR
• MDR
• ACC
• PC

Used to tell the CPU where to locate data in Main Memory

• MAR
• MDR
• ACC
• PC

Stores the results of logic operations and calculations

• MAR
• MDR
• ACC
• PC

Used to store data fetched from memory

• MAR
• MDR
• ACC
• PC

Performance of a CPU: Allows multiple programs to run at the same time

• Multiple Cores
• Clock Speed
• Cache Size

Performance of a CPU: Stores frequently used instructions and data

• Multiple Cores
• Clock Speed
• Cache Size

Performance of a CPU: Measures the amount of FDE cycles a CPU can deal with in a second

• Multiple Cores
• Clock Speed
• Cache Size

The final stage of the CPU cycle

• Fetch
• Decode
• Execute

The stage of the CPU cycle where the Control Unit works out what needs to be done

• Fetch
• Decode
• Execute