Features of flash memory

Question 1

Features of flash memory

Answer 1

• Solid state storage
• Data is non-volatile
• Fast access memory
• Stored as series of logic gates

Question 2

Description of ROM

Answer 2

• Read only memory
• Memory that stores data that cannot be altered, such as boot up instructions. In an embedded system it can store all program instructions.
• ROM is non-volatile(data is not lost when device has no power)

Question 3

Description of flash memory

Answer 3

Limited number of read/writes

Question 4

Examples of primary memory

Answer 4

• RAM
• ROM
• Cache

Question 5

Benefits of flash memory

Answer 5

• No moving parts; therefore durable(not easily damaged)
• Fast access speed(lets devices access and store data more quickly)
• Reliable (data loss is unlikely)
• Small physical size (can fit inside other small devices)

Question 6

Purpose and features of cache

Answer 6

• Primary memory
• Stores frequently used instructions so they are faster to access next time
• The larger the cache, the faster the CPU can access frequently used data

Question 7

Execute stage of FDE

Answer 7

*Execute / carry out the instructions

Question 8

Description of primary memory

Answer 8

• Memory directly accessed bu the processor

* Also known as main memory

Question 9

Description of RAM

Answer 9

• Random-access memory
• Memory that stores currently running data, programs, and currently used parts of the operating system
• RAM is volatile (data is lost when device has no power)

Question 10

Use of flash memory

Answer 10

• Small, portable devices (e.g. mobile phones, satnavs devices that need fast read/write speed)
• Transfer data from one place another, e.g. memory stick/card, SSD
• Can also be used in ROM

Question 11

RAM vs ROM

Answer 11

*RAM is volatile (data is lost when turned off);ROM is non-volatile (data is not lost when turned off)

*RAM can be changed;
ROM cannot be changed

Question 12

Drawbacks of an embedded system

Answer 12

Cannot be updated / very difficult to update and to fix errors

Question 13

Purpose of range check

Answer 13

Make sure the data entered is in the correct format, e.g. dd/mm/yyyy

Question 14

Methods of defensive design

Answer 14

• Validation
• Planning for contingencies
• Anticipating misuse
• Authentication

Question 15

Purpose of formation check

Answer 15

Make sure the data is within the set bounds