In class we covered buffers sppoling and storage devices.
Buffering – a buffer is an area of the computers memory that is allocated to allow the transfer of data betweeen the computer and its peripherals. The buffer is mainly used if the fast part of a computer is comunicating with the slower devies that the computer uses, the buffer does this by storing the data temporarily untill it can be dealt with.
peripheral buffer – A printer operates at a much slower rate that what the cpmuter acts, so a buffer is used so taht the program can still run, instead of waiting for every character to be printed out, the data is sent to the printer by the operating system the usually deals with the buffers.
interface buffers – these are usually called Universal Asynchronous Reciever/Transmitter or UART, this is used to relieve the CPU of continuisly stopping what its doing.
Spooling – If large amounts of data are to be sent to one peripheral device, or if that device is shared between a network of computers tehn the preffered method is to spool, this compensates for the different speed of the proccesors and the peripheral. this allows output files to be queued from many programs and then sent to the printer one by one when the printer is ready.
Storage devices – one type of storage is magnetic storage, these can be found on hard disk drives, floppy disks, sip disks and magnetic tape.they are called magnetic storage because their surfaces are coated in a material that responds to a magnetic feild, these storage devices can be fixed or removable.
hard disks can be slit in to multiple levels with in the hard drive, but the disk its self is also split into different areas called tracks, sectors and cylinders.
