Internal Hardware Flashcards
What is memory used for:
Storing data and instructions
What is RAM:
Random Access Memory
What is ROM:
Read Only Memory
What is main memory:
Memory that stores data and instructions for use by the processor
Define chip:
A small piece of silicon that contains an electronic component
What does it mean for memory to be accessed randomly:
Specific locations are requested and found rather than searching serially through the data until the matching address is found
What are the differences between ROM and RAM:
RAM is volatile, ROM is not RAM stores current programs, ROM stores set-up related instruction sets (BIOS(basic input/output system)) RAM is (re)writable, ROM is not
Standard RAM size:
4-8GB (originally more like 32MB)
What are buses:
Small groups of dedicated parallel wires that transfer data between components in the computer - three types, data, address and control
What does the data bus do:
Carries data between primary storage, the cpu and I/O devices, usually the same width as the memory and processor word length
What does the address bus do:
Takes data from the processor to memory, carries the address of the next instruction/data item, the width controls how much memory can be accessed by the processor, 32 bit is common
What does the control bus do:
Carries control signals to the registers and the other buses, it makes sure everything is synchronised and controls access of components to the other buses, examples include specifying direction of data bus, transmitting the clock pulses
How does word length and width affect buses/the cpu:
The width is how many wires in a bus, and the word length is the number of bits that can be dealt with at once as a unit, so if the width is shorter than the word length, the data has to be split and sent in multiple trips, which is slower
What are some examples of I/O devices:
Mouse, keyboard, monitor, printer
What is an I/O controller:
A piece of hardware that acts as an interface between the I/O devices and the processor
What does the I/O controller provide:
A way of adding new devices without having to redesign the processor, there’s one for each device, they can work as a buffer as they work slower than the processor
What is needed for Von Neumann architecture:
The data and instructions to be stored in the same area of memory and the same bus used to access them - most modern computers use this architecture
What is needed for Harvard architecture:
The data and instructions to be stored in different areas of memory, with different buses for each
Advantages of Harvard architecture:
It’s faster, it’s more efficient, but is mainly used for embedded systems
Define DSP:
Digital signal processing - continuous data is compressed to enable faster processing - chips optimised in this way use less power, so they’re ideal for apps for phones
