Hardware and communication Flashcards
What is cache?
Cache is a small sized type of volatile computer memory that provides high-speed data access to a processor and stores frequently/recently used programs and data.
What is parallelisation?
Parallelisation is technique used to break down large tasks into smaller sub-task to be executed simultaneously on multiple processors or cores
What is the control unit?
coordinates all activities of the CPU
What is clock?
synchronises related components by generates pulses at a constant rate
What is the ALU?
performs arithmetic and logical operations on data (calculations)
What is the program counter?
holds the address of the next instruction to be executed
What is the MAR?
holds the address of the memory location from which data or an instruction is to be fetched or to which data is to be written
What is the MDA?
used to temporarily store the data which is read from or written to memory
What is the CIR?
holds the current instruction being executed
What is the fetch process?
the address of the next instruction is copied from PC to MAR and is then sent through the address bus to RAM. The instruction/data is copied to the MDR and the PC in incremented.
What is the decode process?
the contents of MDR are copied into the CIR and the instruction/data is decoded
What is the execute process?
the instruction is carried out, if it is calculation or logical operation the ALU will process the instruction, the results are stored in the accumulator.
What is magnetic storage?
Magnetic storage devices store data using magnetic fields which include magnetic tapes, floppy disks and hard drives with magnetic storage, it is one of the cheapest forms of storage and the capacity is very large. The limitation is that access times can be slow because they are very delicate.
What is optical storage?
Optical storage devices store data using markers which can be read and written by a laser, it is quite cheap to make and is very lightweight and portable. This makes it the best option for music, films and games, it is also resilient, unlike a magnetic drive. The limitation is that it tends to have slower access times than most modern magnetic and solid-state hard drives.
What is solid state drives?
Solid state drives store data directly onto the silicon microchips electrically rather than magnetically which includes USB, SD cards and portable hard drives. Solid-state storage has no moving parts so it is much more durable than magnetic hard drives which makes it great for mobile devices and tablets, the access times on SSD drives are a lot faster. The limitation is that storage is a lot more expensive than the magnetic and optical alternatives.
