RAM & ROM & Cache

Question 1

what is the primary memory

Answer 1

the only storage that is accessible by the CPU

Question 2

what does the primary memory hold

Answer 2

data and instructions that are currently running on the computer system

Question 3

how are the data and instructions stored in the primary memory

Answer 3

as binary machine code (0s and 1s)

Question 4

what is RAM

Answer 4

it is sometimes referred to as the primary memory when it really is only a branch of the primary memory

Question 5

what does the RAM store

Answer 5

executing program instructions
any data that is needed

Question 6

where are the data and instructions stored in the RAM

Answer 6

in unique memory locations

Question 7

what do each location have

Answer 7

address and content

Question 8

what is the content of the location

Answer 8

where the instructions and data reside

Question 9

what is the address of the location

Answer 9

used by the CPU to find, retrieve, access the data to send it to the ALU for processing

Question 10

is RAM volatile or non-volatile

Answer 10

volatile - whenever power is lost, the contents of the RAM are wiped

Question 11

what is ROM

Answer 11

branch of the primary memory

Question 12

what does ROM hold

Answer 12

data and instructions in unique memory locations

Question 13

what does ROM store (different to RAM)

Answer 13

stores permanent instructions and data that cannot be changed
BIOS (basic input output system)
start-up instructions

Question 14

what is cache

Answer 14

small, high-speed memory inside the CPU used to hold frequently used data from the RAM

Question 15

what does cache allow the CPU to do

Answer 15

it allows the CPU to access the slower RAM less frequently - computer system can run faster

Question 16

what is the difference between SRAM vs DRAM

Answer 16

SRAM: faster, expensive, doesn’t need to be constantly refreshed
DRAM: slower, cheaper, preferred for the main RAM of a computer system, needs to be constantly refreshed

Question 17

where is SRAM placed

Answer 17

small amount of SRAM is placed between the main RAM and the processor (cache)

Question 18

link definition of cache to SRAM, DRAM, knowing that SRAM is a small cache

Answer 18

cache is a smaller, faster RAM (SRAM) that temporarily stores instructions and data so that the processor doesn’t need to access the slower RAM (DRAM)

Question 19

what does the processor do when it needs to read from the main memory

Answer 19

first checks if a copy of the data exists in the cache
if it doesn’t exist, the data is first copied into the cache and then used

Question 20

why is the cache faster than RAM

Answer 20

closer to CPU than RAM with faster read/write speed

Question 21

where is L1 cache placed

Answer 21

on the microprocessor

Question 22

where is L2 cache placed

Answer 22

between primary memory and the processor