Types of processors in the GPU

Advantages of CISC

Advantages of CISC

• Quicker to code programs

• The complier has very little work to do to translate a high-level language statement into machine code

• Because the code is relatively short, very little RAM is required to store the instruction

Advantages for RISC

• The hardware is simpler to build with fewer circuits needed for carrying out complex instructions

• Because each instruction takes the same amount of time, i.e. one clock cycle, pipelining is possible

  e.g. 4 instructions execute same speed as CISC instruction

• RAM is now cheap, and RISC use of RAM and software allows better performance processors at less cost

Disadvantages of CISC

• Many specialised instructions had to be built into the hardware

• Only 20% of specialised instructions are used in the average program.

What do multicore processors do?

distrubute

Supercomputers have ______ of cores

thousnds

What type of problems are supercomputers used for?

Used on problems such as weather forcasting

What is a coprocessor?

What is a GPU

a specialised electronic circuit which is very efficient at manipulating computer graphics and image processing

What does a GPU consist of

t

What is the function of the GPU

A GPU is a coprocessor..

Components of the CPU

• Control Units

• Buses

• Arithmetic-Logic Unit

• Dedicated Registers

What does the Control Unit do?

The part of the processor that coordinates the activity of all other components.

•Directs the flow of data between CPU and other devices

How are Control signals sent

They’re sent along the control bus between the control unit and the other components of the computer

What is a bus?

•Buses in a computer consist of a series of connectors that transfer signals between two or more internal components

What does a system bus consist of?

Control signal/bus
Data Bus
Address bus

What is a system bus

a shared transmission medium where one device can transmit along the bus at any one time.

What is the Control bus and what is it’s purpose?

Control Bus is bi-directional – signals carried out in  both directions

Purpose of the control bus is to:
•Transmit command
•Timing
•Specific status information between system components

What does the control signal include.

•Memory read: causes data from the addressed location in RAM to be placed on the data bus
•Memory write: causes data on the data bus to be written into the addressed location in RAM
•Bus request: indicates that a device is requesting use of the data bus
•Bus grant: indicates that the CPU has granted access to the data bus
•Clock: used to synchronise operations
•Interrupt: indicates a device is requesting CPU access.

What is a data bus?

• The data bus is bi-directional as data can be sent both ways along the bus

• Moves instructions between system components

What is the width in the data bus defined by?

the number of wires or lines it contains

What is the address bus?

•Address Bus transmits the memory addresses of words used as operands in program instructions

•Memory is divided internally into units – words

•Words is a fixed size group of digits, typically 16, 32 or 64 bits – handled as a unit by processor

•Each word in memory has its own specific address
•Data can be retrieved and sent back to processor
•Instruction has been performed > result is stored at a particular memory location > transmitted via data bus