| What does the ALU do? | Performs arithmetic and logic operations |
| What is the role of the control unit? | Controls all the differnt parts of the processor |
| Why are registers really effective for the CPU? | The CPU needs very fast accessible memory and registers are vert fast memory |
| What are the 5 special purpose registers? | PC (Program counter)
CIR (Current instruction register)
MAR (Memory address register)
MBR (Memory buffer register)
SR (Status register) |
| What does the special register PC do? | Used to hold the memory address of the next or the current instruction to be executed in the fetch-execute cycle
Must say both current and next ^ |
| What does the CIR register do? | Holds the instruction that is currently being executed
by the processor |
| What does the memory address register do? | Stores the memory address of a memory location that is to be read from or written to |
| What does the special MBR register do? | Holds the contents of a memory location that has been read from or data that is to be stored. |
| What does the status register register do? | Contains a number of bits, the values of which can change to indicate the occurrence of an interrupt. |
| What does the SR special purpose register stand for? | Status register |
| What do the special purpose registers MBR, MAR and CIR stand for? | Memory buffer register
Memory address register
Current instruction register |
| What does the system clock do? | Synchronises the components |
| What is a register? | A memory/storage location inside the processor |
| By how much would adding just one wire to the address bus increase the memory size | no. wires X 2^1 |
| What mathematically effectively is logic shifting | Doubling or halving |
| Describe what a word is to the processor | The group of bits that is treated as a single unit by the processor |
| What is a core responsible for in a processor? | Completing the Fetch-Execute cycle |
| What 4 ways can the processor execute data? | Reading operand data in to the accumulator from the RAM
Performing arithmetic on operand data
Performing logical functions (conditionals / loops)
Writing data from the accumulator to the RAM |
| What is the role of the processor? | To execute program instructions in order
to run applications |
| Name two types of main memory | 1. Random access memory (RAM)
2. Read only memory (ROM) |
