EoY (chapter 3: VN Architecture, Data Storage, Sensors, Control&Monitoring Systems) Flashcards
What is a CPU
- CPU = central processing unit (AKA microprocesser/processor)
- central to all modern computer systems (including tablets and smartphones)
- executes and processes all the instructions and data in a computer application
What does the CPU consist of
- control unit (CU)
- arithmetic and logic unit (ALU)
- registers and buses
VN Architecture? (4 points)
- John Von Neumann developed the ‘stored program computer’ in mid-1940s
- with VN, programs themselves could be stored in memory, not just data
- in VN architecture, instructions are stored in memory and are retrieved and processed by the CPU one by one.
- VN is based on the principle of fetch-decode-execute (fetch, decode, and execute the instruction)
Main features of VN architecture? (4 points)
- the concept of a central processing unit (CPU)
- CPU being able to access the memory directly
- computer memory storing programs as well as data
- stored programs made of instructions that could be executed in sequential order
fetch-decode-execute?
there is a diagram, check this
registers?
table in the ppt, check this
what are buses?
- buses are used in computers as parallel transmission components
- each wire in the bus transmits one bit of data
what are the 3 types of buses?
address bus
data bus
control bus
address bus?
- carries addresses throughout the computer system between the CPU and memory
- the address bus is unidirectional (bits can travel in ONE DIRECTION ONLY)
- the wider the bus, the more memory locations that can be accessed! width of bus = very important!
data bus?
- data bus is bidirectional (can go both directions, data can be sent both ways)
- data can be carried from CPU to memory, + to-and-from IO devices
- the wider the bus, the more memory locations that can be accessed! width of bus = very important! (like the address bus ^^)
- larger word lengths can improve the computer’s performance
control bus?
- control bus is bidirectional (can go both directions, data can be sent both ways)
- carries signals from the CU (control unit) to all the other computer components
- usually 8 bits wide (since it only carries signals, it doesn’t need to be all that big)
sensors?
see tables in ppt 3.4
Data storage can be split up into?
primary memory
secondary storage
offline storage
primary memory?
- it is the part of the computer memory which can be accessed directly from the CPU
- includes RAM and ROM memory chips
- allows the CPU to access applications and services temporarily stored in memory locations
RAM?
- RAM = random access memory
- can be both written and read
- data can be changed by the user or the computer
- used to store data, files, parts of applications, etc
- it is volatile (volatile = memory is lost when computer is powered off)
ROM?
- ROM = read only memory
- non-volatile (contents/memory aren’t lost when powering off the computer)
- can only be read, (can’t be written)
- they are permanent memory (can’t be changed or re-written)
- usually used to store data that the computer needs to access when first powering up
Secondary + offline storage?
- includes storage devices that aren’t directly accessible by the CPU
- non-volatile (contents/memory aren’t lost when powering off the computer), can be stored
- can store more data than primary memory BUT the data access time is longer than RAM or ROM
- all applications, the operating system, device drivers, general files, photos + music, all stored here
3 categories of secondary (offline) storage?
- magnetic
- solid state
- optical
cloud storage?
- method of data storage where data is stored on remote servers
- the same data is stored on more than one server, allowing clients to access data at any time, very convenient and good in case you lose some files (this is called data redundancy)
- physical environment is owned and hosted by a hosting company
3 systems of cloud storage?
- public cloud (when the customer/client and the storage provider are different companies)
- private cloud (storage provided by a dedicated environment behind a company’s firewall, customer and provider are integrated)
- hybrid cloud (combined of public and private cloud)
input device definition + examples
def: a device that allows data to be exerted into a system
examples:
- 2D scanner
- 3D scanner
- Barcode scanner
- QR codes
- digital cameras
- keyboards
- microphone
- touchscreens
- infra-red
output device definition + examples
def: a device that allows users to see/hear data
examples:
- printers (laser, 3D, inkjet)
- 2D & 3D cutters
- speakers + headphones
- OLED
- Projectors
