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In-depth descriptions of microprocessors and microcontrollers are given, including hardware and software characteristics and support, and a diagram of the design. The microprocessor has migrated from being the central factor in an OEM design to being just another component that must serve as part of a greater whole. The key factor in low end chips is as much small silicon area as it is performance. The key to the high end is the ability to run application software well. The microprocessor's role in Unix systems is to be a good Unix engine, including good synergy with an accompanying C compiler. Mid-range chips revolve around overlapping concerns that optimize low hardware cost and maximize software efficiency. Some microprocessors have exciting technical features, but their allure must be tempered by the knowledge that moving away from standard architectures such as the Z80 and 8086 families means taking risks that available software will dwindle and the chip will become obsolete.

In a complete directory of major vendors of microprocessors aimed at the microcomputer market, design specifications are provided along with limits and design features for each microP.

Designers enjoy freedom of choice with support chips. They aren't tied to popular operating systems as much as they are with microprocessors. It was at first thought that support chips, such as number crunchers, special graphics generators, cache controllers, coprocessors, and many more, would be used primarily in high priced work stations, but they've found application in smaller systems as well. There are now so many that a complete listing would fill an issue, so this directory is condensed.

A directory of 'microprocessor-like' digital signal processors (DSP) is given, including manufacturers, products, availability, cost, description, hardware and software specifications, chip diagrams, and hardware and software support. To be microprocessor-like means the chips access and execute instructions like a microprocessor but with DSP's high-speed sum-of-products algorithm; Number-crunching capacity can even match some superminicomputers. Speed is achieved with: single-cycle hardware multipliers, Harvard architectures, in which instructions are fetched in parallel with data, simultaneous data feed to both sides of the multiplier; bit-reversal addressing, in some cases; and other features indicated in the directory. Products include: 16-, 24-, 22-, 16-10-, and 24-12-bit, NMOS and CMOS, and fixed-point and floating-point DSP designs. Certain programmable chips are excluded as too specialized.

The 68000 and the 8086 microprocessors are the top all-purpose semiconductor components, according to the rankings of micro-controllers and microprocessors made by EDN in its 1987 chip directory. The directory is also highlighted by the recent popularity of ASIC cell library microprocessors. The 16-bit 8086 components, which includes 80286 and 80186 components, accounted for 60 percent of total 16-bit semiconductor shipments during 1985. Roughly 25 percent of the total shipments for 16-bit semiconductors in the 68000 family during 1985 were accounted for by 68010 and 68000 components.

Replacement technologies have enhanced the appeal of classical TTL. Some technologies, however, will reduce its appeal. There is definitely a place for high-speed CMOS TTL.

After 10 years the microprocessor revolution has reached maturity with very large and foreign corporations beginning to dominate. The microprocessor has won a position as the foundation of almost all electronic applications. Opportunities for OEM designers lie in the design of such products as sophisticated controllers, 16- and 32-bit machine applications, and micromainframe implementation.

The increasing use of digital-signal-processing (DSP) microprocessors is making the design of filters for DSP systems a more important - and time-consuming - part of the designer's job, and for designers unfamiliar with the mathematics of DSP filter design, several software packages are available that facilitate the process. For developing systems of filters for high-speed modems, speech recognition systems, or adaptive noise cancellers, for example, a high level of expertise is required; but lowpass, highpass, bandpass, or bandstop digital filters can be designed in an hour when one of the software programs described is used. The programs reviewed are the Digital Filter Design Package (DFDP), version 2.0, from Atlanta Signal Processors Inc. ($1,195); a set of digital-processing programs from IEEE Inc., furnished as a nonprofit service ($36.60 in book form, $62.95 on half-inch tape); the Interactive Laboratory System (ILS) from Signal Technology Inc. ($995 for PC-1 basic module and $1,495 for PC-2 add-on module); Digital Signal Processing Software (DISPRO), version 1.5, from Signix Corp. ($1,450); and Modular-Access Design, Computer-Aided Processing (MADCAP) from Whitman Engineering Inc. ($1,595).

The use of CMOS chips is spreading to the entire 4-bit and 8-bit microprocessor market and even to the 16- and 32-bit-device market. CMOS chips are used as replacements for NMOS devices and in place of TTL microprocessor parts. Chipmakers are incorporating CMOS in their designs in the classical CMOS form where p-n ratio remains 50:50, in commercial CMOS form where 40:60 or 20:80 p-n ratios may serve, and in specialized CMOS form where a small number of p devices are needed.

Digital signal processing chips are seen as a major advance in chip technology. The complex nature of DSP devices has slowed down development. The advantages of DSP are expected to be low-cost general programmability and bus compatibility.

The digital-signal-processing chip from Texas Instruments may mark the start of general-purpose use of these DSP devices. The TI TM320 chip is the first DSP device which is also a 1-chip microcomputer incorporating a powerful arithmetic-logic unit and multiplier. The wide use expected of this chip will probably allow a reduction in price to the $10 level considered the threshhold for general market penetration.

Support chips are in transition from discretes to ASICs Today's support chip is tomorrow's ASIC cell. If you're a devotee of EDN's Annual μP Support-Chip Directory, you know this statement [...]

New software tools run IBM PC software on a variety of 32-bit μPs Most industry observers agree that the vast wealth of MS-DOS-based software is what gives the 8086 μP [...]

Intel Corp will use a new trace scheduling and compacting compiler incorporating fine-grain parallelism in its upcoming 80860 reduced instruction set computing (RISC) processor. The technology, developed by Multiflow Computer Inc, overlaps instruction execution in very long instruction word (VLIW) compilation and schedules data precedence at compile time. It will allow four to seven parallel units in the new RISC chip. Critics say the new design will result in slower compilation because the ever-growing number of decisions in a microprogram will force it to work harder. The new chip will use an architecture similar to that of current Intel superscalar chips., VLIW compiler to take i860 'hyperscalar' BRANFORD CT--A trace scheduling and compacting compiler that exploits inherent fine-grain parallelism, developed by Multiflow Computer Inc, will be employed by a forthcoming version [...]

Microchip Technology Inc enhances its PIC microcontroller with a faster, 1.9-micron (L effective) CMOS process and a fine-tuned RISC-like two-stage pipeline, which provide a 5-MHz instruction cycle and a peak performance of 5 MIPS in a single-chip, 8-bit microcontroller. The lopsided Harvard architecture of the PIC widens instructions to 12 bits, which allows most of the PIC's instructions to execute in one cycle; the Motorola 6805 and Intel 8051 microcontrollers have multicycle instruction rates. The PIC has only 512 words of instruction memory at present, however, compared to 8 and up to 16 kwords on chip for its competitors. The PIC is also able to execute algorithms directly, whereas most other microcontrollers have to look them up in a table. Use of pipelining means that branches or anything else that disrupts the pipeline cause the pipeline to halt momentarily., PIC takes RISC-like pipeline to 5 MIPS A faster, 1.9-[micrometer] (L effective) CMOS process and a fine-tuned RISC-like 2-stage pipeline have brought new life to the 14-year-old PIC microcontroller. The [...]