1.1 Characteristics of Contemporary Processors Flashcards
(27 cards)
Name and describe three buses used to convey information between the special registers.
- Control bus - transmits control signals from the control units to other parts of the processor.
- Data bus - carries the data from one place to another.
- Address bus - carries the location address where the data is going to or from.
Explain the need for the program counter (PC).
It is needed to store the address of the next instruction to be processed, the value is sent to the MAR and afterward the value of the PC is incremented.
Explain the need for the memory address register (MAR).
Contains the address of the instruction to be accessed in memory sent from the PC.
Explain the need for the memory data register (MDR).
Contains the data which has been accessed from memory and that is to be referenced by the MAR.
Describe two ways in which the accumulator is used.
- Temporary storage during calculations.
2. I/O in processor and is used as a buffer.
Describe the role of the control unit in the processor.
It decodes instructions and controls the buses.
Describe how fast clock speed improves a processor’s performance.
More instructions can be exexcuted per second so the program takes less time to run.
Describe how a large cache memory improves a processor’s performance.
There would more space for instructions/data and accessing cache is quicker than accessing the RAM.
Give a Little Man Computer instruction that will copy the contents of the accumulator into memory when executed.
STA
Compare a Complex Instruction Set Computer (CISC) architecture with a Reduced Instruction Set Computer (RISC) architecture.
For CISC there is a complicated processor design which makes the intergrated circuit expensive, whereas RISC has a simple processor design making it less expensive. CISC has many instructions available whereas for RISC there is a limited number of instructions available.
Explain one advantage, other than cost, of RISC compared with CISC.
Programs run faster due to simpler instructions.
Explain the effect of using a co-processor system for complex calculations for scientific research.
Calculations are done by the maths co-processor so processing is faster when using floating point arithmetic.
Explain the effect of using a co-processor system for priniting personalised letters to customers for an advertising campaign.
There is no increase in speed as there are no calculations so the co-processor isn’t suited to the task.
One feature of Von Neumann architecture is that instructions are executed in a linear sequence.
Give three other features.
- Single control unit.
- One instruction at a time.
- Uses fetch execute cycle.
Describe the differences between RISC and CISC architectures.
CISC is more complicated and RISC is simpler.
RISC takes one machine cycle whereas CISC takes many cycle to complete one instruction.
RISC requires more RAM.
CISC has many addressing modes.
Describe the fetch-decode-execute cycle.
Fetch- The next instruction is fetched from main memory/address.
Decode - The instruction is split into opcode and operand in the CIR.
Execute - Opcode is carried out the operand.
An architect firm specialises in designing skyscrapers. Give one use the firm might have for GPUs.
To render models of propesed buildings.
Describe what is meant by the term ‘RAM’.
Random Access Memory. Type of primary, volatile memory.
State one characteristic a high performance CPU might have.
Multiple cores.
A gaming company decides to release a new video games console. As well as a CPU the console contains a GPU for 3D graphics. Explain why a GPU is more suitable than a CPU for this task.
CPUs are general purpose processors whereas GPUs are designed specifically for graphics. Therefore they are likely to have built in instructions for common graphics instructions making onscreen graphics quicker than a CPU.
The office workers of a large company each use a stand-alone computer.
The finance manager needs to work on some files at home and also to assess new software for use in the finance department.
State three different storage devices that the finance manager would use and describe what each device would be used for.
- Hard drive to store files and software.
- Memory stick to allow transport of materials between office and home.
- Cloud storage to make files available to others in the department.
Explain two advantages of the monitoring system of ICU patients having its operating system stored in ROM.
ROM is quick to start up so the system can be started up quickly in an emergency.
ROM cannot be altered so there is no chance of the OS being accidentally or maliciously changed.
Describe what happens to the contents of RAM and ROM when power to the system is removed.
The contents of RAM are wiped whereas the contents of ROM remain the same.
State two differences between RAM and ROM in a typical PC computer system.
RAM is volatile whereas ROM isn’t.
RAM is editable whereas ROM cannot be altered.
