4.7 - Fundamentals of computer organisation and architecture Flashcards
What does the Accumulator do?
Stores result of calculations processed by ALU.
What does the Memory Buffer Register do?
Stores data read from memory.
What does the Memory Address Register do?
Stores address of memory location processor needs to access.
What does the Status Register do?
Used to store information about the state of the CPU or a particular operation, such as whether a previous calculation resulted in a zero or a negative number. Each bit within this register checks for errors or exceptions, or disables interrupts.
What does an Input/Output controller do?
act as an interface between peripheral devices and the core computer
Why does an Input/Output controller need to be used?
Because the CPU won’t be able to interpret the signals received from the peripheral device without it
What does the Current Instruction Register do?
Stores current instruction being executed.
What do General Purpose Registers do?
They act as fast memory used to temporarily store and access results of operations. Connected to ALU.
What does the Program Counter do?
Stores address of the next instruction to be executed
What are the uses of RFID tags?
Labels concealed within products.
ID cards used to open doors
Library cards
Track movements of farm animals
What does an RFID tag do?
Made of antenna for transmitting and receiving radio signals. Also contains a chip which processes these signals. Each tag has a unique identifier. Can be read only or read and write.
What does an RFID reader do?
It transmits an encoded radio signal to query the tag. The tag receives the message and responds with an identifier/stored data.
How does the Input/Output controller work?
It manages data communications to and from peripheral devices. This saves the processing power of the CPU which would otherwise be wasted.
What is RFID for?
RFID (radio frequency identification) allows data to be transmitted over radio waves. Uses a tag and a reader, doesn’t require line of sight for the reader.
What is the difference between passive and active RFID tags
Passive RFID tag - No power supply, uses radio signals transmitted by the reader. Uses the energy from the transmitter to active the chip. Range of 1m.
Active RFID tag - Small battery within the tag, transmits its identifier regularly. Range up to 200m.
What is an Interrupt Service Routine (ISR)?
ISR is a software routine that is called when an interrupt occurs. The ISR determines how to handle the interrupt. For example when a key is pressed on a keyboard the ISR will determine which key was pressed.
What does a device driver do?
Allow the operating system to communicate with a peripheral device, which allows the device to be made for any operating system.
What are Interrupts?
In computing, an interrupt is a signal that temporarily stops the CPU from executing its current program or task and redirects it to handle a higher-priority task. An interrupt can be triggered by either hardware or software.
What is a bus?
A communication system that is used to transfer data between components
Examples of hardware interrupts?
Keyboard interrupt: Generated when a key is pressed or released on the keyboard.
Mouse interrupt: Generated when a mouse button is pressed or released, or when the mouse is moved.
Network interrupt: Generated by a network interface card to indicate that a packet has been received or sent.
What is a system bus?
A bus which uses parallel connections to allow internal components to communicate with each other and exchange data.
Examples of software interrupts?
Open: Used to open a file for reading or writing.
Close: Used to close an open file.
Read: Used to read data from an open file.
Write: Used to write data to an open file.
What is an external bus?
buses which are used to connect peripherals to the processor. They can be either serial or parallel connections