Part 1 Block 3 - Hardware & Software Concepts Flashcards
The p_______________ of a computer is the part that actually performs the instructions that we ask the computer to execute.
processor
In the processor, what is the ALU, and what is the FPU
The arithmetic logic unit (ALU)
floating-point unit (FPU)
ALU - Arithmetic Logic unit
The ALU contains the electronic circuits that perform b________ a____________, such as addition, subtraction, multiplication and division on i___________, as well as circuits to perform logical operations, such as c____________ integers with zero, testing two integers for equality, testing if one integer is greater than another, etc.
binary arithmetic
integers
comparing
FPU - Floating Point Unit
Its function is very similar to that of the ALU, but it operates on f________-p_______ numbers using specialised circuitry optimised to be as efficient as possible.
floating point
Main memory is a s_______ a__________ that contains program instructions and data.
storage area
When a program is first loaded, the corresponding instructions and data are put into main memory.
Is main memory inside or outside the processor?
Outside
Main memory is sometimes referred to as
R_____.
RAM
Where is the cache memory?
Inside the processor or outside of the processor?
Inside
‘Registers’ are memory locations.
Registers are very small but very fast areas of memory that are used as a holding area for instructions and data immediately before they are needed by the A___/F____
ALU/FPU
To calculate a percentage increase in time:
= new time - original time
___________________________ x 100%
original time
If the original time was 1.00 x 10^-7
and the new time is 1.09 x 10^-7
What is the percentage increase in time?
A 9% increase in time.
Step 1:
1.09 x 10^-7 - 1.00 x 10^-7
= 0.09 x 10^-7
Step 2:
0.09 x 10^-7
_____________
1.00 x 10^-7
= 0.09
Step 3:
0.09 x 100%
= 9%
Each instruction and piece of data is held in a ‘chunk’ called a w______.
word
A word has a fixed size (usually 32 or 64 bits in a modern computer), and it is handled as a u______ by the hardware of the processor.
unit
As each ‘word’ gets closer to being processed, it is moved into the processor so that it can be accessed more quickly. This movement from main memory into the processor usually happens in two steps:
First, the word is moved to c_______ memory which is inside the processor
then from c________ memory to memory locations called r__________.
cache
cache
registers
Registers are very small but very f______ areas of memory that are used as a h______ a_____ for instructions and data immediately before they are needed by the ALU/FPU.
fast
holding area
The result of the operation is returned via r__________ and the c_________ memory, back to m________ memory.
registers
cache memory
main memory
More about cache memory
Like the registers, cache memory is included on the p___________ microchip.
processor microchip
More about cache memory
Cache memory is used as an i____________ storage area between the registers and the main memory.
intermediary
More about cache memory
If there were no cache memory, a b___________ of data and instructions trying to get into and out of the processor would occur.
This is because the speed of data written to and read from the processor’s registers is much f___________ than the speed of reading from and writing to main memory.
bottleneck of data
faster
More about cache memory
In modern processors, there may be s_________ levels of cache memory.
several levels
More about cache memory
Which level of cache is fastest and smallest?
Level 1 or Level 2
Level 1
the aim is to use this for the data and instructions that will imminently be transferred to the registers.
Organise the areas of memory in terms of speed.
main memory, cache, registers
1 = registers
2 = cache
3 = main memory
In general, the f__________ the memory, the more e______________ the engineering required to make it.
faster
expensive
More about cache memory
Data has to be moved into cache memory from main memory b____________ it is needed by the processor.
before
Therefore the use of the cache to speed up execution depends on how effective the cache management is at predicting future data use.
More about registers
There are a number of different types of register in different parts of the p_________, and each is designed to hold a particular type of information for a specific function.
processor
More about registers
The register within the ALU where an actual calculation takes place is sometimes referred to as the a____________________.
accumulator
The processor contains several general-purpose registers that can be used as accumulators.
More about registers
What is the name of the register, sometimes called the flags register, that holds further information about the last operation executed?
The status register
Each bit in the register represents some description of the result – is the result zero? Is the result negative? Is the result too big to be stored in the accumulator? And so on. The values in the status register act as a report on the result of the recent activity in the processor.
The control unit and other registers
The control unit has the role of c________________ the m____________ of data and instructions within the processor.
It does this by sending out electrical pulses, called c_________ s___________, that activate the necessary connections between main memory, cache, registers, ALU and FPU, as required, to execute the instruction.
coordinating the movement of data
control signals
The a_________ r_____________ holds the location in memory (the memory address) of the next instruction to be executed.
address register
