5.6 (a) Flashcards
(24 cards)
List the main components of a basic computer system?
- Input Section
- Output Section
- CPU (Central Processing Unit)
- Memory Section
- Interconnecting Buses
List the types of inputs and outputs of a computer?
Inputs:
- Analog - Smooth changing voltage
- Digital -Series of high low level voltages (1 or 0)
- Discrete - on/off condition (closure of relay)
Outputs:
- DA converter (Digital to Analogue)
- Digital Transmitter (conversion then transmit digital bus)
- binary (requires dimultiplexer)
Which data format does a computer use?
Binary
How is analogue data converted for use in a computer?
an A/D converter
Analogue to Digital Converter
How is serial data converted for use in a computer?
A multiplexer converts it into a ‘Word’
In a computer what do the following terms mean:
a) Word
b) Byte
c) Bit
d) BITE
a) A complete unit of binary information or data is called a word
b) A Byte may be a word or only part of a word. 8 bits = 1 Byte
c) A bit is a numerical value either 1 or 0
d) BITE = Built in Test Equipment
A memory capacity of 64k = _________
65,536 bits
comma
Describe an Address Bus?
16 mono-directional lines. The lines originate from CPU and are connected to the memory and I/O ports.
Address is where to deliver it, content is data to be delivered
Series of high lows on these 16 mono-directional lines tells where address is
Where does an Address Bus originate from?
The CPU
16 mono-directional lines
Describe a Data Bus?
8 bi-directional lines and facilitates transmission of data between CPU ,memory and I/O ports
What does a Data Bus interconnect?
CPU memory and I/O
transfer of data on 8 bi-directional lines
Describe a Control Bus?
10 - 12 mono and bi directional lines
4 functions:
- Memory
- Input - Output
- MPU
- Utilities such as clock
List the four functions of a Control Bus?
- Memory Synchronisation
- Input - Output
- MPU (Memory Protectional Unit)
- Utilities such as a clock
What is meant by mono-directional?
One direction
Address bus identifies addresses using 16 mono-directional lines
Control bus uses 10 - 12 mono and Bi directional lines
Describe the role of a CPU, identifying its main parts?
CPU = Central Processing Unit
Main part of computer
Register Section
ALU (Arithmetic/logic unit)
Control Unit
What is:
a) Software
b) Hardware
c) Firmware
d) Machine Code
a) Software - program which is a list of instructions
b) Hardware - pile of electronical and mechanical components
c) Firmware = Un-alterable software
d) Machine Code = ?
What would be stored in firmware?
Firmware = Un-alterable software
example = Operating program
What is meant by non-volatile memory?
Non-volatile memory is used to store programs
I.E if computer turned off, non-volatile memory data is not lost upon start up again
What is meant by volatile memory?
Volatile memory is temporary data
I.E When computer is turned off, data is lost upon start up
Identify the types of memory that are non-volatile?
Which requires most power, SRAM or DRAM?
DRAM = Dynamic Random Access Memory - low power require with high memory capacity
SRAM = Static Random Access Memory - high power but twice as fast as DRAM
SRAM requires the most power
Compare EPROM and EAROM?
EPROM = Erasable Programmable Read Only Memory
Whole software usually erased and new written in - Usually by UV light 5 - 20 mins
EAROM = Electrically Alterable Read Only Memory
can be re programmed without sun light in situ etc
individual cells erased and reprogramed
Why are disks and tapes ‘‘Secondary Memory Systems?’’
They contain magnetic surface recording media and are generally slower mediums of memory but large storage capacity
Differentiate between primary and secondary memory?
Primary memory = fastest memories made of semiconductor IC’s eg ferrite cores
Seconadary memories = Mass storage devices + magnetic surface recording media
