Operating system and computer architecture Flashcards
What is an Operating System?
Software running in the background of a computer. It manages many of basic functions. It also makes it possible to communicate between HW and SW
Give examples (5) of what basic functions OSs control
HCL (Human computer interface), Multitasking, Multiprogramming, Interrupt handling, Real-time processing
What type of OS is Windows?
Single-user multitasking operating system
What does ROM stand for?
Read only memory (can’t be changed)
What does ROM run?
BIOS (basic input-output system), processor, hardware, processor, internal memory
What is an interrupt?
A signal sent from a device or from software to the processor
Give 4 examples of interrupts
- A disk drive is ready to receive more data
- An error has occurred, such as a paper jam in a printer
- The user has pressed a key to interrupt the current process - ALT F4
- A software error has occurred - an exe file couldn’t be found
What does the proccessor do with the interrupt?
The procesor either carries on with what it was doing or stops to service the device/program that generated the interrupt
Why are interrupts useful?
They allow computers to carry out many tasks or to have several windows open at the same time
Give an example of how an interupt could be useful?
An example would be downloading a file from the internet at the same time as listening to music at the same time.
How is a status of the current task saved as an interrupt is serviced?
It is done using an interrupt handler, once the interrupt is serviced the paused task continues.
What are Buffers?
They are used in computers as a temporary memory area
Why are Buffers essential?
They are essential since hardware devices operate at much slower speed than the processor. If it wasn’t for buffers prcessors would spend the majority of their time idle, waiting for hardware to comple its operation
Give an example of Buffers being used.
For example, when streaming a video from the internet. It ensures that the video play back doesn’t keep on stopping to wait for fata from the internet.
When did John von Neurmann develop the idea of a sotred program computer?
1945
What was the concept called that John von Neumann came up with?
Von Neumann Architecture
What was the ideas within the Von Neumann Architecture concept?
To hold programs and data in a memory. Data would then move between the memory unit and the processor.
What links the processor and memory units?
Buses
What is an adress bus?
Carries signals relating to addresses between the processor and the memory