Editing Flat memory model (section)

{{More citations needed|date=December 2009}}

'''Flat memory model''' or '''linear memory model''' refers to a [[memory address]]ing paradigm in which "[[computer memory|memory]] appears to the program as a single contiguous [[address space]]."<ref>{{cite book|last1=Gonzalez|first1=Antonio|last2=Latorre|first2=Fernando|last3=Magklis|first3=Grigorios|title=Processor Microarchitecture: An Implementation Perspective|year=2011|publisher=Morgan & Claypool Publishers|isbn=9781608454525|page=72|url=https://books.google.com/books?id=3fW4HiTiUo4C&dq=Processor+Microarchitecture%3A+An+Implementation+Perspective&pg=PP1}}</ref> The [[CPU]] can directly (and [[addressing mode#Sequential addressing modes|linearly]]) [[memory address|address]] all of the available [[computer memory|memory]] locations without having to resort to any sort of [[bank switching]], [[memory segmentation]] or [[paging]] schemes.

Memory management and [[CPU cache#Address translation|address translation]] can still be implemented ''on top of'' a flat memory model in order to facilitate the [[operating system]]'s functionality, resource protection, [[computer multitasking|multitasking]] or to increase the memory capacity beyond the limits imposed by the processor's physical address space, but the key feature of a flat memory model is that the entire memory space is linear, sequential and contiguous.

In a simple controller, or in a ''single tasking'' embedded application, where memory management is not needed nor desirable, the flat memory model is the most appropriate, because it provides the simplest interface from the programmer's point of view, with direct access to all memory locations and minimum design complexity.

In a general purpose computer system, which requires multitasking, resource allocation, and protection, the flat memory system must be augmented by some memory management scheme, which is typically implemented through a combination of dedicated hardware (inside or outside the CPU) and software built into the operating system. The flat memory model (at the physical addressing level) still provides the greatest flexibility for implementing this type of memory management.