MC68030

MC68030
Name	MC68030
Designer	Motorola
Bits	32-bit
Introduced	1987
Data-width	32
Address-width	32
Design	CISC
Transistors	~300,000
Frequency	16 MHz to 50 MHz
Socket	PGA
Predecessor	Motorola 68020
Successor	Motorola 68040

MC68030. The MC68030 is a 32-bit microprocessor introduced by Motorola in 1987 as an enhanced successor to the Motorola 68020. It integrated key peripheral functions, such as a memory management unit, directly onto the main CPU die, improving performance for multitasking operating systems. The chip saw widespread adoption in high-performance workstations, personal computers, and embedded systems throughout the late 1980s and early 1990s.

Overview

The MC68030 emerged during a period of intense competition in the microprocessor market, with rivals like Intel advancing its 80386 architecture. Engineers at Motorola aimed to create a highly integrated and efficient processor for the burgeoning Unix workstation and advanced personal computer markets. Its release was strategically important for companies such as Apple Computer, which utilized it in models like the Macintosh IIci and Macintosh IIfx. The processor's balance of performance and integration made it a cornerstone for many systems developed by Sun Microsystems, NeXT, and Commodore International.

Architecture

Architecturally, the MC68030 built upon the foundation of the Motorola 68020 but incorporated significant enhancements. Its most notable improvement was the inclusion of an on-chip, demand-paged Memory management unit with a 256-byte translation lookaside buffer. The processor featured a highly parallel execution unit and separate instruction and data caches, each 256 bytes. It maintained full compatibility with the extensive Motorola 68000 family instruction set while adding new capabilities for improved performance in complex applications and operating systems like Unix System V.

Technical specifications

The MC68030 was fabricated using HCMOS technology and contained approximately 300,000 transistors. It operated at clock speeds ranging from 16 MHz to 50 MHz, with a typical performance rating around 18 MIPS at 50 MHz. The processor supported a 32-bit external data bus and a 32-bit address bus, enabling direct access to 4 GB of physical memory. It included a flexible coprocessor interface, most commonly used to attach a Motorola 68881 or Motorola 68882 floating-point unit. The chip was packaged in a 128-pin Pin grid array or Ceramic leaded chip carrier.

Variants

Several variants of the MC68030 were produced to cater to different market segments and power requirements. The 68EC030 was a cost-reduced version that omitted the on-chip Memory management unit, targeting embedded control applications. Motorola also produced low-power versions for portable and battery-operated systems. Some variants featured static core design, allowing the clock to be stopped entirely for minimal power consumption, which was valuable in aerospace and military applications from contractors like Lockheed Martin.

Applications and usage

The MC68030 found extensive use in a diverse array of computing platforms. It was the CPU for several influential Apple Macintosh models, the NeXT Computer, and later models of the Commodore Amiga such as the Amiga 3000. In the workstation arena, it powered systems from Sun Microsystems (like the Sun-3 series) and Silicon Graphics. Its reliability and performance also made it a popular choice in telecommunications equipment, laser printers from Hewlett-Packard, and avionics systems. Many real-time operating systems, including VxWorks, were ported to the platform.

Legacy and successors

The MC68030 cemented the reputation of the Motorola 68000 family as a premier architecture for technical and professional computing throughout the late 1980s. It was directly succeeded by the more powerful Motorola 68040, which integrated a floating-point unit and larger caches. While the entire lineage was eventually overshadowed by the rise of RISC processors from IBM, MIPS Technologies, and Advanced Micro Devices, the 68030's design philosophy influenced later embedded processors. Its architecture lived on for decades in niche markets and within the enduring community of Amiga and Classic Mac OS enthusiasts.

Category:Motorola microprocessors Category:32-bit microprocessors Category:1987 introductions