The CPU controls data transfer and operations, directing data to the ALU for calculations and ensuring correct data paths. It works with the system clock for synchronization. The ALU performs calculations and logic functions and determines relationships between values. Registers like the accumulator and address register store instruction and results. Buses transport signals between components, and the fetch-execute cycle fetches instructions from memory, decodes and executes them, then stores results.

3. Controls all the operations in the CPU Transfers data to registers Directs data to ALU for calculation Ensures correct paths for data transfer Synchronisation with the system clock Click on image to go to the Fetch-Execute Cycle

4. Performs calculations Tests logic functions Determines relative relationships between values Click on image to go to the Fetch-Execute Cycle

5. Storage register Stores the next instruction to be executed Accumulator Stores the latest results from a calculation Address register Stores memory address locations Instruction register Stores instructions to be processed Click on image to go to the Fetch-Execute Cycle

6. The system clock is an accurate, very fast electronic timer. The faster the system clock the more instructions per second are executed.

7. Buses are pathways – separate wires / metallic strips which transport signals (data). http://www.webopedia.com/TERM/b/bus.html

8. Fetch: The instruction is fetched from memory. Instructions are stored in registers . Decode the opcode is decoded by the CU so the instruction can be executed. Execute The instruction is executed, usually using the ALU . Store The result of the instruction is stored. Note: this is a simplified explanation (what is required knowledge for the Preliminary course – see link for further detail). http://en.wikipedia.org/wiki/Instruction_cycle

9. Decode: The typical instruction is divided into two parts: the Opcode and the Operand The opcode is the instruction. The operand is the data on which the instruction needs to be performed. In the simplified example below: Add 10 Add would be the instruction (opcode). 10 would be the data (operand).

10. More input / output devices Increased processing speed Larger memory (both primary and secondary) which is better for working with sound and graphics