ch4 Flashcards
(31 cards)
what’s a system clock
produces timing signals on the control bus to ensure synchronisation takes place
what’s IAS
immediate access store
holds all data and programs needed to be accessed by the control unit
what’s a core
a unit made up of ALU, control unit and registers which is part of a CPU. A CPU may contain a number of cores
ehats dual core and quad core
a cpu that contains two cores
and a cpu that contains 4 cores
what’s SR
status register
used when a i structure requires some form of arithmetic of logical processing
what’s Flag
indicates the status of a bit in the SR
what’s HDCP
High bandwidth digital copy protection
part of HDMI tech which reduces risk of piracy of software and multimedia
what’s RTN
short hand notation to show movement of data and instructions in a processor, can be used to represent the operation of the fetch decode execute cycle
what’s clock cycle
clock speeds are measured in terms of GHz
this freq of the clock which sends out pulses along the control bus
3.5GHz means 3.5 billions clock cycles per second
what’s overclocking
chaning the clock speed of a system clock to a value higher than the factory/recommended setting
what’s BIOS
basic input output system
what’s index register
used when carrying out index addressing operations (assembly code)
what’s MAR
Stores address of the memory location currently being read from or written to
what’s MDR
stored data which has been read from memory or data which is about to be written to memory
explain what each of the CPU thingys do
- the PC contains the address of the next instruction to be fetched
- the address contained in the PC is copied to the MAR via address bus
- the instruction is then copied to the MDR
- the entire instruction is then copied from the MDR and placed in the CIR
- the value in the PC is then incrmemebwnted so that it points to next instruction to be fetched
- the address part of the instruction is placed in the MAR
- the instruction is finally decoded and then executed
what’s the function of address bus and data and control bus
address — transmits address between the processor and memory
it’s UNIDIRECTIONAL
data — sends data between the processor, memory and input devices
BI DIRECTIONAL
control — signals sent by processor to control the memory and peripheral devices
BIDIRECTIONAL
how can a computers performance be made better
by altering bus width by making them longer and increasing clock speed and using multi core CPUs
what’s pros and cons of USB
pros
device plugged is automatically detected due to voltage change
the connectors can only fit one way so prevents incorrect connections
industry standard so found easily
newer usb are still compatible with older usb
CONS
the present transmission rate is limited to less than 500mb per second
the max cable length is presently about five metres
the older USB standard may not be supported in the near future
what’s HDMI
It allows an output of both audio and visual from computer to HDMI enabled devices replacement to VGA
uses widescreen format
the screen use a greater number of pixels
screen has faster refresh rate
the range of colours is extremely large
what’s VGA
Supports 640x480 pixel resolution on tv. it handles refresh rate of up to 60Hz provided there are only 16 diff colours being used soooo it supports up to 256 colours
pros and cons of HDMI
PROS
the current standard model
allows for very fast transfer rate
improved security
supports modern digital systems
CONS
not very robust connection
limited cable length to retain good signal
there are 5 cable standards
what’s pros and cons of VGA
PROS
- simpler tech
- only one standard available
- connection is very secure
- it’s easy to split the signal and connect a number of devices
CONS
- old out dated
- it’s easy to bend the pins when making a connection
- cable must be very high grade to ensure good undistorted signal
what’s an assembler
it translate each assembly language instruction into a machine code instruction
it also checks syntax and ensures only OPCODES from the appropriate machine code instruction set are used
what are the two assemblers and how are they used
Single pass assembler — it puts the machine code instructions straight into the computer memory to be executed
two pass assembler — produces an object program in machine code that can be stored, loaded then executed at a later stage using a loader
it needs to scan the source program twice so that they can replace labels in the assembly program with memory addresses in the machine code program
