Concept
Memory management unit
Related concepts (49)
Motorola 68020
The Motorola 68020 ("sixty-eight-oh-twenty", "sixty-eight-oh-two-oh" or "six-eight-oh-two-oh") is a 32-bit microprocessor from Motorola, released in 1984. A lower-cost version was also made available, known as the 68EC020. In keeping with naming practices common to Motorola designs, the 68020 is usually referred to as the "020", pronounced "oh-two-oh" or "oh-twenty". The 020 was in the market for a relatively short time. The Motorola 68030 was announced in September 1986 and began deliveries in the summer of 1987.
Memory segmentation
Memory segmentation is an operating system memory management technique of dividing a computer's primary memory into segments or sections. In a computer system using segmentation, a reference to a memory location includes a value that identifies a segment and an offset (memory location) within that segment. Segments or sections are also used in s of compiled programs when they are linked together into a and when the image is loaded into memory.
Translation lookaside buffer
A translation lookaside buffer (TLB) is a memory cache that stores the recent translations of virtual memory to physical memory. It is used to reduce the time taken to access a user memory location. It can be called an address-translation cache. It is a part of the chip's memory-management unit (MMU). A TLB may reside between the CPU and the CPU cache, between CPU cache and the main memory or between the different levels of the multi-level cache.
Motorola 68000
The Motorola 68000 (sometimes shortened to Motorola 68k or m68k and usually pronounced "sixty-eight-thousand") is a 16/32-bit complex instruction set computer (CISC) microprocessor, introduced in 1979 by Motorola Semiconductor Products Sector. The design implements a 32-bit instruction set, with 32-bit registers and a 16-bit internal data bus. The address bus is 24 bits and does not use memory segmentation, which made it easier to program for.
Workstation
A workstation is a special computer designed for technical or scientific applications. Intended primarily to be used by a single user, they are commonly connected to a local area network and run multi-user operating systems. The term workstation has been used loosely to refer to everything from a mainframe computer terminal to a PC connected to a network, but the most common form refers to the class of hardware offered by several current and defunct companies such as Sun Microsystems, Silicon Graphics, Apollo Computer, DEC, HP, NeXT, and IBM which powered the 3D computer graphics revolution of the late 1990s.
VAX
VAX (an acronym for Virtual Address eXtension) is a series of computers featuring a 32-bit instruction set architecture (ISA) and virtual memory that was developed and sold by Digital Equipment Corporation (DEC) in the late 20th century. The VAX-11/780, introduced October 25, 1977, was the first of a range of popular and influential computers implementing the VAX ISA. The VAX family was a huge success for DEC–over 100 models were introduced over the lifetime of the design, with the last members arriving in the early 1990s.
Motorola 88000
The 88000 (m88k for short) is a RISC instruction set architecture developed by Motorola during the 1980s. The MC88100 arrived on the market in 1988, some two years after the competing SPARC and MIPS. Due to the late start and extensive delays releasing the second-generation MC88110, the m88k achieved very limited success outside of the MVME platform and embedded controller environments. When Motorola joined the AIM alliance in 1991 to develop the PowerPC, further development of the 88000 ended.
Cache (computing)
In computing, a cache (kæʃ ) is a hardware or software component that stores data so that future requests for that data can be served faster; the data stored in a cache might be the result of an earlier computation or a copy of data stored elsewhere. A cache hit occurs when the requested data can be found in a cache, while a cache miss occurs when it cannot. Cache hits are served by reading data from the cache, which is faster than recomputing a result or reading from a slower data store; thus, the more requests that can be served from the cache, the faster the system performs.
Motorola 68030
The Motorola 68030 ("sixty-eight-oh-thirty") is a 32-bit microprocessor in the Motorola 68000 family. It was released in 1987. The 68030 was the successor to the Motorola 68020, and was followed by the Motorola 68040. In keeping with general Motorola naming, this CPU is often referred to as the 030 (pronounced oh-three-oh or oh-thirty). The 68030 is essentially a 68020 with a memory management unit (MMU) and instruction and data caches of 256 bytes each.
Memory protection
Memory protection is a way to control memory access rights on a computer, and is a part of most modern instruction set architectures and operating systems. The main purpose of memory protection is to prevent a process from accessing memory that has not been allocated to it. This prevents a bug or malware within a process from affecting other processes, or the operating system itself. Protection may encompass all accesses to a specified area of memory, write accesses, or attempts to execute the contents of the area.