Mrs Roberts Comp Sci Flashcards
(63 cards)
What is a Computer
A combination of hardware, software, user and data
Why was the Von Neumann computer architecture made?
To allow not only data to be stored in the memory but also the program processing the data
What are the 3 main parts of the Von Neumann computer architecture
1) The ALU (Arithmetic Logic Unit)
2) The Registers
3) The CU (Control Unit)
What is the CPU in a computer / what does it do
The CPU (Central Processing Unit) is the brain of the computer which executes programs, manages the hardware of the computer and gets data & instructions from memory
What is the fetch-decode-execute cycle
The fetch-decode-execute cycle describes the process of getting data from memory, decoding the data and executing whatever process is in the data
What are the components of a Modern Computer
1) The CU (Control Unit)
2) The ALU (Arithmetic Logic Unit)
3) The Registers
4) The Buses
5) The Cache Memory
What is one issue with the Von Neumann computer architecture
Only one instruction can be processed at once
What are the factors that affect CPU (Central Processing Unit) performance
1) Material
2) Clock Speed (Faster clock = More cycles/s)
3) Cores (Each core is its own processor)
4) Cache Size
5) Word Size
Define Word Size
The maximum amount of bits a CPU can manipulate as one unit
What are the 3 bus types
1) Address bus (links CPU and RAM)
2) Data bus(The CPU puts ‘Fetch’ signals on this bus)
3) Control bus(sends signals to all the hardware)
What are the 3 types of memory
1) RAM (Random Access Memory)
2) ROM (Read Only Memory)
3) Cache
What are the characteristics of RAM
1) fast read & write access
2) Volatile (Contents destroyed when machine is powered down)
3) Used to store currently running programs
What are the characteristics of ROM
1) Larger than RAM
2) Non - Volatile
3) Stores important programs e.g. Boot strap loader or BIOS
What are the characteristics of Cache
1) Closer to the CPU than RAM
2) Faster than RAM
3) Volatile
4) Low capacity
5) Stores frequently used data
What is Virtual Memory
If there isn’t enough RAM available, hard drive space can be used as ‘pretend’ RAM which is much slower
What is Multi-tasking
The CPU manages several programs by swapping between them very quickly because it performs billions of instructions a second
What are all the Registers
1) Program Counter
2) Memory Address Register (MAR)
3) Memory Buffer Register (MBR)
4) Current Instruction Register (CIR)
5) Accumulator
6) Memory Data Register (MDR)
What are Embedded systems
A computer system with a dedicated function within a larger system
What is Parallel Processing
When a task is split into 2 or more processes to reduce processing/loading time
What are the types of Secondary Storage Devices
1) Magnetic
2) Optical
3) Solid State
4) Cloud-based
What are the characteristics of Magnetic Storage Devices
1) Reliable
2) High capacity at low cost
3) can be internal or external
4) Stores the OS, user data and programs
What are the positives of magnetic storage devices
1) Supports how computers work
2) High capacity
3) Fast read & write speeds
4) Non-Volatile
5) Cheap cost per megabyte
What are the negatives of Magnetic Storage devices
1) Slower than ROM
2) HDDs (Hard Disk Drives) can crash
3) Regular crashes damage the surface of the disk
4) Not easily transferred
What are the characteristics of Optical storage devices
1)Lasers are used to read and write to the disks
2) The laser is reflected back, then the light reflected can be read as a 1 or 0
