1.1 Systems Architecture Flashcards
What is a CPU, and what does it do?
The Central Processing Unit. It carries out all the commands and processes information.
What is clock speed?
The clock speed is how many FDE (Fetch Decode Execute) cycles the CPU can do in a second. It is measured in Hz (Hertz)
what are some of the characteristics of cache
- faster than RAM
- Stores commonly used instructions
- Volatile and small
- Really expensive
what is the PC and what does it do?
Program counter
Stores the address of the next instruction to be run, it increments by one each time
How does the number of cores affect CPU speed?
The cores act as another CPU.
The more cores means more instructions can be carried out.
However it is only useful when the applications are programmed to handle it.
What is the ACC and what does it do?
Accumulator.
Holds the data (number) that you are currently working on / result from ALU.
What is the MAR and what does it do?
Memory Address Register.
Contents of the PC are copied here.
Stores the address where the next data will be fetched from
What is the MDR and what does it do?
Memory Data Register.
Stores data / instructions being brought back from the RAM.
What is the CIR and what does it do?
Current Instruction Register.
The instructions / data in the MDR are copied here.
Data Bus
Carries data around (can go both ways)
Address Bus
Carries around addresses (can only go one way)
Control bus
Sends signals to the RAM to either re-write or bring the data back
What is the ALU and what does it do?
Arithmetic Logic Unit.
Does the arithmetic (mathematical) and logic calculations within the computer.
What is the CU and what does it do?
Control Unit.
Manages the data:
Controls where data goes and monitors the flow of data.
Executes instructions.
Sends control signals between the different internal components.
What is Von Neumann Architecture?
Data + instructions are stored in the same RAM location. The FDE cycle is then used to decode and execute instructions.
