Motorola 68000

The Motorola 68000 ("'sixty-eight-thousand'"; also called the m68k or Motorola 68k, "sixty-eight-kay") is a 16/32-bit<ref "16/32">Motorola Literature Distribution, Phonenix, AZ (1992). Motorola M68000 Family Programmer's Reference Manual (PDF). [motorola]. pp. 1–1. ISBN 0-13-723289-6. </ref> CISC microprocessor core designed and marketed by Motorola Semiconductor Products Sector (Freescale Semiconductor until December 2015, now NXP). Introduced in 1979 with HMOS technology as the first member of the successful 32-bit m68k family of microprocessors, it is generally software forward compatible with the rest of the line despite being limited to a 16-bit wide external bus. After 35 years in production, the 68000 architecture is still in use.

History

The 68000 grew out of the MACSS (Motorola Advanced Computer System on Silicon) project, begun in 1976 to develop an entirely new architecture without backward compatibility. It would be a higher-power sibling complementing the existing 8-bit 6800 line rather than a compatible successor. In the end, the 68000 did retain a bus protocol compatibility mode for existing 6800 peripheral devices, and a version with an 8-bit data bus was produced. However, the designers mainly focused on the future, or forward compatibility, which gave the 68000 platform a head start against later 32-bit instruction set architectures. For instance, the CPU registers are 32 bits wide, though few self-contained structures in the processor itself operate on 32 bits at a time. The MACSS team drew heavily on the influence of minicomputer processor design, such as the PDP-11 and VAX systems, which were similarly microcoded.

Motorola

Motorola, Inc. (/ˌmoʊtəˈroʊlə/) was a multinational telecommunications company based in Schaumburg, Illinois, United States. After having lost $4.3 billion from 2007 to 2009, the company was divided into two independent public companies, Motorola Mobility and Motorola Solutions on January 4, 2011. Motorola Solutions is generally considered to be the direct successor to Motorola, Inc., as the reorganization was structured with Motorola Mobility being spun off.

Motorola designed and sold wireless network equipment such as cellular transmission base stations and signal amplifiers. Motorola's home and broadcast network products included set-top boxes, digital video recorders, and network equipment used to enable video broadcasting, computer telephony, and high-definition television. Its business and government customers consisted mainly of wireless voice and broadband systems (used to build private networks), and, public safety communications systems like Astro and Dimetra. These businesses (except for set-top boxes and cable modems) are now part of Motorola Solutions. Google sold Motorola Home (the former General Instrument cable businesses) to the Arris Group in December 2012 for US$2.35 billion.