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A family of [CPU]s made by [Motorola], sometimes also referred to as "68k".

The design has 16 32-bit registers, split into 8 data and 8 address registers. The instruction set is quite orthogonal and instructions are always multiples of 16 bits in length. Accesses to anything larger than a byte have to be 16-bit aligned. Overall, the architecture has a strong [RISC] feel to it, though it is not. It has always been fully 32-bit, as opposed to the [x86] design, which started out as a 16-bit design that was painfully evolved to 32-bit.

The 68000, the first in the series, was introduced in September 1979, and only had a 24-bit address bus. The 68010, introduced in 1982, allowed the use of VirtualMemory, but most customers decided the [MMU] alone offered insufficient advantage to justify the expense over its predecessor, so they waited for the 68020 instead. The 68020, which debuted in 1984, was fully 32-bit, and software could immediately take advantage of this because the architecture had always been designed for the fact. The 68k family enjoyed wide deployment, and is nowadays still used in embedded devices. Some architectures built around this [CPU] family include:

* The AppleLisa and the AppleMacintosh.
* The Commodore [Amiga].
* The [Atari] ST.
* The Sega Genesis and ~MegaDrive.
* The [HP] 9000/300 series.
* The Q40 and Q60 (Sinclair QL successors).
* The [NeXT] workstation.
* The original SunMicrosystems [UNIX] machines.
* The Apollo/Domain workstations.
* VMEbus single-board computers from BVM, Motorola and Tadpole.
* Until recently, the PalmPilot [PDA]s.
* In any number of lasers printers, such as [HP], Printronix, [Adobe], [IBM], Lexmark and others more.
* In countless architectures, as peripheral controllers and signal processors.

The original 68000 design was in production by Motorola up until 2000, and is still in production under license by others, along with its successors and many licensed derivatives of all the designs of the family. Innumerable devices employ these [CPU]s even today.

You can run [Linux] on a range of [680x0]-based systems thanks to the effort of the [Linux/m68k project | http://www.linux-m68k.org/]. Ports exist to a variety of systems; f.ex., on later AppleMacintosh~es that use the 68030 and upwards (such as the SE30), its [Linux/mac68k subproject | http://www.mac.linux-m68k.org/] allows running [Debian]. See the [Linux/m68k project | http://www.linux-m68k.org/] for more architectures.
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Last edited on Thursday, July 7, 2005 9:54:26 am by AristotlePagaltzis
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