James Bowes - Post 16 Computer Science

A multi-purpose machine is a machine that can only carry out one task at once. A program can must be loaded into the machine, decoded, processed and executed before the next one can be fetched. It is called multipurpose because it can do lots of different tasks, just only one task can be carried out at a time. An example of this is the John Von Neumann Architecture .  It was designed in the 1940s and follows the idea that programs and data are stored on memory and then accessed by the processor when required. This is then passed between the processor and memory unit via one bus. Instructions and data are stored together in memory. The  Harvard Architecture is an adaption of the Von Neumann Architecture . It works in the same way but stores the data and programs separately (each connected by a separate bus) so the two can be accessed simultaneously. Von Neumann Architecture Vs Harvard Architecture: Modern day ( Contemporary Processor Architec

Memory management involves calculating and assigning certain amounts of memory to each task in a certain way to gain optimal performance from the computer. There are three ways computers can manage memory: Paging Paging is where the RAM is split into equal pieces. Pages are the equal segments that make up the RAM. They are used to identify and locate data (they are what data is stored on and labelled as).   For example: each page makes up 10kb of the RAM. A 15kb piece of data would take up 2 pages (so 5kb of RAM would be wasted) and then that data would be labelled as being on pages 1 & 2. Segmentation Segmentation allows each of the segments to be fluid (so they can adjust to the size of the file). So a 15kb bit of data could use one segment of 10kb and another segment of 5kb. No RAM would be wasted however this does make monitoring how much storage is left in the RAM more difficult to predict for the computer. Virtual Memory Virt