Cromemco

Cromemco, Inc.
Company type	Private
Industry	Computer hardware
Founded	1974
Founder	Harry Garland, Roger Melen
Defunct	1987
Fate	Acquired by Dynatech Corporation
Successor	Dynatech Computer Systems
Headquarters	Mountain View, California, United States
Area served	International (including United States, Europe, Greece)
Key people	Harry Garland (President), Roger Melen (VP of R&D)
Products	Microcomputers, computer peripherals, digital cameras, graphics adapters, operating systems (CDOS, CROMIX)
Owner	Harry Garland and Roger Melen (until acquisition)
Number of employees	Over 500 (by 1983) (1983)
Parent	None until acquisition; then Dynatech Corporation

Cromemco, Inc. was a microcomputer manufacturer based in Mountain View, California, known for producing advanced Z80-powered S-100 bus systems and accessories during the formative years of the personal computing era.

Established in 1974 by Stanford doctoral candidates Harry Garland (serving as President) and Roger Melen (Vice President of R&D), the company derived its name from their Stanford residence, Crothers Memorial Hall. Incorporated two years later in 1976, Cromemco initially introduced pioneering devices such as the Cromemco Cyclops digital camera and the Cromemco Dazzler color graphics adapter before progressing to full computer system production.

By December 1981, Inc. magazine recognized Cromemco as one of the ten fastest-growing privately owned companies in the United States. The firm was acquired in 1987 by Boston-based Dynatech Corporation, subsequently operating under the name Dynatech Computer Systems.

Early history

The roots of Cromemco date back to 1970 when Garland and Melen, then graduate students at Stanford, collaborated on electronic projects aimed at hobbyists, which were published in Popular Electronics. To support their initiatives, they licensed components from external suppliers; notably, a 1973 “Op Amp Tester” kit was retailed by MITS, the same company that later introduced the Altair microcomputer.

In 1974, during a visit to Popular Electronics in New York, Melen encountered the prototype of the MITS Altair. Impressed by the potential, he adjusted his travel plans to meet Ed Roberts, president of MITS, who encouraged him to develop add-on hardware for the Altair. This collaboration resulted in the creation of the Cyclops digital camera showcased in the February 1975 issue of Popular Electronics.

After returning to California, Garland and Melen established Cromemco to manufacture the Cyclops camera and subsequent microcomputer products. The company’s name paid homage to Crothers Memorial Hall at Stanford University, where their partnership originated.

First products

The initial product development by Melen and Garland included the Cyclops Camera interface designed for use with the Altair computer, which led to several important innovations. To overcome limitations associated with punched paper tape storage, they engineered a programmable read-only memory card known as the “Bytesaver”. This device allowed programs to be stored permanently and enabled immediate system startup with resident software, quickly becoming a favored accessory for both Altair and IMSAI computers.

To facilitate displaying images captured by Cyclops on color television sets, Cromemco launched the Dazzler graphics card in 1976. This advancement extended Altair’s functionality into visual applications such as gaming. Since there was no existing joystick interface, Cromemco developed the D+7A interface card along with a joystick console featuring an 8-bit digital channel accompanied by seven analog channels. Beyond gaming applications, the D+7A was utilized for data acquisition and industrial computing purposes, marking Cromemco’s strategic entry into scientific and technical markets.

Promoting themselves as “Specialists in Computer Peripherals,” Cromemco built a reputation for inventive design coupled with robust construction quality. Their initial emphasis on peripheral devices enabled them to capitalize on the S-100 bus, originally developed for Altair computers, as a platform for creating their own computer systems—signaling a transition toward expanded product lines and accelerated business development.

From circuit boards to complete systems

Cromemco introduced its inaugural computer, the Z-1, in August 1976. It was equipped with 8K of static RAM and utilized a Zilog Z80 microprocessor, setting it apart from rivals that relied on the Intel 8080 chip. The subsequent model, the Z-2, arrived in June 1977, featuring an expanded 64K RAM and support for Cromemco DOS (CDOS), an operating system similar to CP/M. This version also enhanced connectivity by incorporating a parallel port and eliminating the extensive switch panel present on the Z-1.

The product range advanced with the release of the System One, System Two, and System Three series. Debuting in 1978, the System Three was designed for professional multiuser settings, supporting programming languages such as FORTRAN IV and Z80 BASIC. It also offered optional peripherals including hard disk drives, CRT terminals, and printers.

Cromemco crafted proprietary software solutions like CDOS and CROMIX—a multiuser Unix-like operating system launched in 1979. CROMIX leveraged banked memory technology to accommodate up to six simultaneous users and initially operated on the System Three. Later, it was extended to systems powered by Motorola 68000 processors.

Cromemco S-100 Microcomputer Systems (Z-80 Processor)
System	Year Released	Number of S-100 Slots	Internal Floppy Drives	Internal Hard Drive	Supported Operating Systems
Z-1	1976	21	—	—
Z-2	1977	21	—	—	CP/M
System Zero	1980	4	—	—	CP/M, Cromix
System One CS-1	1981	8	2 x 5-inch floppy drives	—	CP/M, Cromemco DOS, Cromix
System One CS-1H	1981	8	1 x 5-inch floppy drive	5 megabytes	CP/M, Cromemco DOS, Cromix
System Two Z-2D	1978	21	2 x 5-inch floppy drives	—	CP/M, Cromemco DOS, Cromix
System Two Z-2H	1980	12	2 x 5-inch floppy drives	11 megabytes	CP/M, Cromemco DOS, Cromix
System Three	1978	21	4 x 8-inch floppy drives	—	CP/M, Cromemco DOS, Cromix

In 1982, the company introduced a dual-processor CPU card (DPU) combining a Motorola 68000 with a Zilog Z-80 to maintain backward compatibility. This development led to the transformation of their product lines into the 100-, 200-, and 300-series models corresponding to Systems One through Three respectively, along with a new tower-style 400-series. Subsequent CPU cards such as the XPU and XXU delivered improved processing capabilities based on the Motorola 68000 family.

Also in that year, Cromemco unveiled the C-10 personal computer aimed at entry-level users. This floppy disk-based system with a Z-80 processor ran CDOS and came bundled with business applications including spreadsheet software, word processors, and BASIC programming environments.

Cromemco S-100 Central Processing Units
CPU Card	Year Released	Microprocessor	Clock Speed	Performance (Whetstone Benchmarks)
ZPU	1976	Z-80A	Switchable between 2 MHz and 4 MHz	7,000
DPU	1982	Z-80A/MC68000	4 MHz / 8 MHz	40,000
XPU	1984	Z-80B/MC68010	5 MHz / 10 MHz	50,000
XXU	1986	MC68020 with MC68881 coprocessor	16.7 MHz	1,050,000

By the year 1983, Cromemco had expanded its workforce to over five hundred employees and reported annual revenues reaching US$55 million. It held a leading position in sales of S-100 based computer systems. The company remained privately owned by founders Harry Garland and Roger Melen until its acquisition by Dynatech Corporation in 1987—a significant customer through its subsidiary ColorGraphics Weather Systems.

Although the European division restructured as Cromemco AG before eventually entering liquidation in 2018, the Greek branch established in 1978 under Information Systems & Control Ltd. continues to operate as Cromemco Hellas S.A., maintaining selective international market presence.

Engineering Achievements

Cromemco earned distinction for its superior engineering quality, innovative design, and dependable system performance. Roger Sippl, an early team member, described the company’s adaptable research and development culture that empowered engineers to explore their passions. The firm was a trailblazer in microcomputer advancements, introducing groundbreaking technologies such as the first digital camera (the Cyclops Camera), the initial color graphics adapter (the Cromemco Dazzler), the first programmable storage unit (Bytesaver), pioneering memory bank switching methods, and the earliest commercially available Unix-like operating system (Cromix).

The engineering workforce primarily originated from Stanford University, the Homebrew Computer Club, and Cromemco’s distribution partners. Students connected to the founders—including Joe McCrate, Curt Terwilliger, Tom McCalmont, Jerry May, Herb Lewis, and Marvin Kausch—made notable contributions. Engineers like Ed Hall and Li-Chen Wang joined from the Homebrew Computer Club community, while Nik Ivancic, Boris Krtolica, and Egon Zakrajšek arrived through Cromemco’s Yugoslavian distributor, bringing specialized knowledge in structural engineering software.

Several prominent engineers later transitioned into entrepreneurship. Roger Sippl, Laura King, and Roy Harrington co-founded Informix Corporation, a leading database software company. Tom McCalmont went on to establish REgrid Power Inc. and McCalmont Engineering with a focus on renewable energy solutions. Jeff Johnson founded UI Wizards, Inc., becoming a recognized author in software user-interface design.

These engineering innovations and leadership trajectories emphasize Cromemco’s strategic influence in advancing Silicon Valley’s technological ecosystem through innovation, talent development, and commercial expansion.

Significant Deployments

In 1981, Cromemco microcomputers were chosen by the United States Air Force Systems Command for the Theater Air Control System (TACS) after evaluation against 149 competitors, underscoring the company’s edge in defense technology applications. The Air Force subsequently became a key purchaser, acquiring 1,500 units.

To support the Air Force's Mission Support System (MSS), Cromemco engineered the CS-250—a customized variant of its CS-200 computer featuring patented removable hard disk technology. From 1985 through 1996, approximately 600 CS-250 units were utilized for mission planning on F-15, F-16, and F-111 aircraft platforms, with initial deployment during Operation Desert Storm in 1991.

The United States Navy also integrated Cromemco systems aboard vessels and Ohio-class submarines for essential roles such as speech synthesis within the Aegis Combat System's Combat Information Center. This certification distinguished Cromemco as the first commercially available microcomputer authorized for naval operations.

Within commercial sectors, Cromemco established a significant presence at the Chicago Mercantile Exchange (CME), where 60 Z-2 systems equipped with Octart interface cards managed trade processing from 1982 until their replacement by IBM PS/2 machines in 1992. This achievement highlighted Cromemco’s strong position in financial technology markets.

Globally, Cromemco was an early entrant into China’s computing industry, selling over 10,000 systems to Chinese universities by 1985, illustrating its pioneering international reach.

Moreover, Cromemco systems dominated U.S. television broadcast technology for news and weather graphics production. By 1986, more than 80 percent of major-market TV stations relied on Cromemco hardware combined with ColorGraphics Weather Systems software solutions, demonstrating the company’s broad industry impact through diversified offerings.

In popular culture

The Cromemco System One Computer made a notable appearance in the 1984 movie Ghostbusters, where it was seen inside the Ghostbuster Laboratory. In his 2011 autobiography, Idea Man, Microsoft cofounder Paul Allen praised the Cromemco Cyclops Camera as one of the earliest digital cameras, first introduced in 1976. That very year, Mona Simpson mentioned having contemplated buying a Cromemco as her initial personal computer.

The Cromemco System Three took center stage in Andrew Bujalski's 2013 film Computer Chess. Additionally, in 2013, author Deborah Perry Piscione cited Cromemco alongside Apple Inc. as key Silicon Valley pioneers instrumental in shaping the personal computing landscape. In 2018, the Smithsonian National Museum of American History incorporated the Cromemco C-10 computer into its permanent collection.

External links

Stanford University: "Cromemco History" page. A summary of the company's founding and development.
Collection of downloadable photos, manuals, and software for Cromemco S-100 systems.
Cromemco Z-1 brochure (circa 1976).
"Cromemco Z-2D" Zilog Z80-based S-100 computer (circa 1977).
"Cromemco System One" Specifications and image of Motorola 68000 system (circa 1982).
Additional perspective on the "Cromemco System One".
The compact "Cromemco System Zero" Six-slot S-100 computer.
Review of "Cromemco C-10SP" from Creative Computing magazine, January 1984 edition.
Photographs, specifications, and advertisement for "Cromemco C-10" personal computer (circa 1982).
Information on "Cromemco CS-100 & CS-300" models (circa 1984–1985).
Details on "Cromemco CS-250" Motorola MC68020 S-100 system (circa 1990).
"Cromemco CS-250" with Maxtor 190MB hard drive (circa 1990).
Comprehensive Cromemco Part Number Cross-reference covering systems, boards, peripherals, and manuals.
Digibarn's collection of Cromemco systems
Dave's Old Computers, including images, disk images, and documentation.
Early advertisements for hard drives
Advertisement for Cromemco HDD Disk Memory System at Classic Computer Brochures site.
X:\static\S100\cromemco, software archives and documentation.
The sole CPU card delivering 4MHz speed.
CROMIX: Cromemco's UNIX-like operating system.