3 Flashcards
1
Q
Computer
A
- Takes some kind of input and processes it to produce and output
- Made up of hardware and software
2
Q
Von Neumann concept
A
- Stored program concept - allowed both program instructions and data to be stored together in a computer’s main memory
3
Q
RAM
A
- Random-access memory
- Consists of a collection of storage locations, each with its own unique memory address
4
Q
Control unit
A
- Decodes instructions received from main memory
- Coordinates the actions of the other parts of the CPU in order to execute them
5
Q
Arithmetic logic unit
A
- Performs arithmetic and logic operations on data
6
Q
Registers
A
- Proved fast temporary storage for instructions, intermediate results, and data
7
Q
Instruction register
A
- Holds the instructions currently being executed
8
Q
Accumulator
A
- Holds the results of calculations from ALU
9
Q
Fetch-decode-execute-cycle
A
- CPU fetches an instruction from memory
- Decodes the instruction
- Executes the instruction
10
Q
Address bus
A
- Carries the address of the memory location that the CPU will read and write to
- Unidirectional
11
Q
Data bus
A
- Holds the value being read from or written to memory
12
Q
Control bus
A
- Carries command signals from the control unit to other components so that they know whether to read or write data
13
Q
Cache
A
- Very fast storage which contains frequently used intructions and data
14
Q
Clock
A
- Sends out electronic signals at regular intervals to all the other hardware components in order to synchronise their actions
15
Q
Fetch
A
- The control unit places the memory address of the next instruction on the address bus
- It sends a read signal to RAM along the control bus
- The RAM receives the signal and copies the content of the memory location indicated by the address bus onto the data bus
16
Q
Decode
A
- The control unit decodes the instruction
17
Q
Execute
A
- The control unit sends signals to the other components of the CPU instructing them what to do
18
Q
Pipelining
A
- The CPU executes programs more quickly by overlappping the stages of the fetch-decode-execute cycle
19
Q
Why is secondary storage needed?
A
- Storage of programs and data when the power is turned off
- Semi-permanent storage that can change
- Backup of data files
- Archive of data files
20
Q
Magnetic storage + 3
A
- Data is stored on the surface of a platter as a series of bits
- An area that is magnetised represents a 1 and an area that is demagnetised represents a 0
- To write the magnetic states is altered, to read te magnetic states are detected
1. Has high storage capacity
2. Quick to access data
3. Has moving parts which eventually fail