Magnetic Peripherals

Control Data Corporation
Company type	Corporation
Industry	Computer hardware, Supercomputers
Predecessor	Engineering Research Associates (ERA)
Founded	September 1957
Founder	Robert Perkins, William R. Keye, Howard Shekels, Robert Kisch, Seymour Cray, William Norris (CEO)
Fate	Withdrew from computer production by 1988; formed Control Data Systems, Inc. in 1992; remaining branches continue as Dayforce (software firm)
Successor	Control Data Systems, Inc.
Headquarters	Minneapolis, Minnesota, United States
Area served	Worldwide
Key people	Seymour Cray (Chief Designer), William Norris (CEO)
Products	Mainframe computers, Supercomputers, Peripherals (tape drives, card readers/punches, printers), Vocational training (Control Data Institute)

Adapted from the English Wikipedia article Magnetic Peripherals, available under CC BY-SA 4.0Updated 8 August 2025

Control Data Corporation (CDC) was a prominent mainframe and supercomputer manufacturer during the 1960s, recognized as one of the nine leading American computer companies alongside IBM, Burroughs, DEC, NCR, General Electric, Honeywell, RCA, and UNIVAC. CDC's reputation was primarily built on the innovations of electrical engineer Seymour Cray, who created several of the fastest computers of that period. In the 1970s, Cray departed from CDC to establish Cray Research (CRI), dedicating his efforts solely to supercomputing technology. After experiencing substantial financial setbacks in the 1980s, CDC began withdrawing from computer production by 1988 and sold off associated subsidiaries; in 1992, it formed Control Data Systems, Inc.. The company's remaining branches continue today under the software firm Dayforce.

Background: World War II – 1957

During World War II, the U.S. Navy assembled a covert engineering group tasked with creating codebreaking devices for deciphering Japanese and German communications. To maintain this team after the war despite reductions in military budgets, the Navy arranged for John Parker of Northwestern Aeronautical Corporation in St. Paul, Minnesota, to employ them without revealing their specific activities. This arrangement resulted in the establishment of Engineering Research Associates (ERA) in 1946, a contract engineering company responsible for early military stored-program computers such as the ERA Atlas—the forerunner to the Univac 1101 series.

In the early 1950s, ERA faced political and legal obstacles related to Navy ownership that depleted its resources, leading Parker to sell ERA to Remington Rand in 1952. Remington Rand later merged with Sperry Corporation to form Sperry Rand, integrating ERA into Sperry’s UNIVAC division. Within Sperry’s corporate framework, ERA encountered managerial restrictions and project delays, particularly during the development of UNIVAC II.

Frustrated by Sperry’s bureaucratic environment, several leading engineers—including Robert Perkins, William R. Keye, Howard Shekels, Robert Kisch, and Seymour Cray—resigned to create Control Data Corp. in September 1957. They established their operations in Minneapolis near Sperry’s St. Paul facility. William Norris was named CEO while Seymour Cray became chief designer after completing a transistor-based prototype computer for the Naval Tactical Data System (NTDS), designated AN/USQ-17 (M-460), which still utilized tube rectifiers within its power supply.

Early designs and Cray's big plan

CDC initially focused on marketing subsystems such as drum memory units to other firms. Cray joined CDC the following year and developed a compact transistor-based 6-bit machine called the "CDC Little Character" to experiment with concepts for large-scale system design. This machine was regarded as a significant achievement.

In 1959, CDC introduced a 48-bit transistorized redesign of the ERA-Univac 1103 called the CDC 1604; its first delivery was made in 1960 to the U.S. Navy at the Naval Postgraduate School in Monterey, California. The "1604" model number is said to combine CDC’s original address (501 Park Avenue) with an earlier project number from Cray’s work, although this explanation remains debated within company lore.

Also released in 1960 was a 12-bit variant known as the CDC 160A, often considered among the earliest minicomputers and uniquely designed to fit within a standard office desk. The architecture of the 1604 evolved into the CDC 3000 series, which achieved strong sales throughout the early to mid-1960s.

Cray immediately set out to design what would become the fastest computer worldwide, aiming for performance fifty times greater than that of the 1604. This ambitious undertaking encountered delays spanning four years, generating frustration among management and calls for increased supervision. In response, Cray demanded in 1962 that he be allowed to move to an isolated laboratory in Chippewa Falls, Wisconsin—threatening resignation if denied. CDC founder Bill Norris consented, granting Cray full autonomy over his lab—Norris himself required invitations to enter the facility.

Peripherals business

In the early 1960s, the company moved its operations to the Highland Park area of St. Paul, where Norris resided. Believing that CDC required a substantial "critical mass" to effectively challenge IBM, Norris launched an assertive acquisition campaign aimed at broadening CDC's peripheral product offerings. The objective was to produce peripherals that outperformed IBM’s by 10% in speed while costing 10% less—an ambitious benchmark.

The initial peripheral developed was a tape transport device. Internal discussions debated whether other divisions should be charged for these units; eventually, a profit-sharing arrangement was implemented between the Peripherals Equipment Division and the sales divisions, a system later adopted throughout the corporation.

Subsequently, the 405 Card Reader and 415 Card Punch were introduced, followed by a range of internally engineered tape drives and drum printers. The printer segment initially collaborated with Holley Carburetor near Detroit through a joint venture named Holley Computer Products, which CDC later fully acquired and transformed into its Rochester Division.

Train and band printers emerged from a partnership with NCR and ICL called Computer Peripherals, Inc. (CPI), where CDC held majority control. In the early 1980s, CPI merged with Centronics, a manufacturer specializing in dot matrix printers.

Norris sought to disrupt IBM’s dominance in punched cards by acquiring Rabinow Engineering, a leader in optical character recognition (OCR) technology. The plan aimed to replace punched cards with OCR-compatible typed sheets to enhance data density and processing efficiency. Although CDC initially led in OCR innovation, persistent technical difficulties led to the closure of Rabinow’s facility in 1976 as CDC withdrew from the OCR sector.

Acknowledging the ongoing importance of punched cards, CDC purchased Bridge Engineering to provide card punches that were both faster and more cost-effective. Following Bridge's relocation, card-handling products were transferred to the Valley Forge Division along with tape transports. Both Valley Forge and Rochester divisions were spun off into the joint venture CPI with NCR and later ICL to share development and manufacturing expenses. In 1982, Centronics acquired the Rochester Division.

Norris’s diversification efforts also included launching service bureaus targeting smaller firms unable to invest in computers directly. Despite these bureaus’ limited profitability and management recommendations for closure in 1965, Norris opposed such cuts and instead enforced company-wide cost reduction measures.

Control Data Institute

From the mid-1960s through the late 1980s, Control Data founded an international vocational school specializing in technical and computer training known as the Control Data Institute. By the late 1970s, it operated sixty-nine centers globally, educating approximately 18,000 students.

CDC 6600: defining supercomputing

At the Chippewa Falls facility, Seymour Cray, Jim Thornton, and Dean Roush led a team of 34 engineers focused on enhancing the CDC 1604 by incorporating faster silicon transistors sourced from Fairchild Semiconductor. The outcome was the CDC 6600, launched in 1964, which outperformed rival systems by roughly a factor of ten. More than 100 units were sold at $8 million each (equivalent to about $ million today), earning it recognition as a groundbreaking supercomputer.

The CDC 6600 featured a transistor-based CPU operating at 100ns with multiple asynchronous functional units supported by ten external I/O processors that handled routine input/output operations, freeing the CPU to concentrate entirely on data processing tasks. Utilizing advanced compiler technology, it achieved approximately 500 kiloFLOPS; finely tuned assembly code could reach near 1 megaFLOPS performance. A simpler and less costly serial processor version was marketed as the CDC 6400, alongside a two-processor variant known as the CDC 6500.

A FORTRAN compiler called MNF (Minnesota FORTRAN) was developed specifically for the 6600 by Lawrence A. Liddiard and E. James Mundstock at the University of Minnesota.

In response, IBM initiated the ACS-1 project in 1965 aiming to surpass the CDC 6600’s speed capabilities. Despite innovative architectural designs produced by a dedicated West Coast team, incompatibility with IBM's System/360 architecture led to cancellation of ACS-1 in 1969. This failure resulted in significant attrition among IBM’s high-performance computing personnel.

Simultaneously, IBM announced its System/360 Model 92 promising performance on par with the CDC 6600. This announcement caused CDC sales to decline sharply. In retaliation, CDC chairman Norris filed an antitrust lawsuit against IBM which culminated in an $80 million settlement including acquisition of IBM's subsidiary Service Bureau Corporation (SBC), complementing CDC’s existing service bureau operations.

During development of the CDC 6600, Project SPIN concentrated on designing high-speed hard disk storage solutions. It investigated both fixed and removable disk formats and delivered a large 28" fixed disk alongside a smaller multi-platter removable disk-pack system measuring 14". This project laid groundwork for CDC’s extensive hard disk product line.

CDC 7600 and 8600

In the same month that CDC prevailed in its legal battle against IBM, it unveiled the CDC 7600 (initially known as the 6800). The 7600's hardware operated at nearly quadruple the clock rate of the 6600 (36 MHz compared to 10 MHz), featuring a 27.5 ns clock cycle and achieving over four times the processing throughput by extensively utilizing pipelining techniques.

Despite its advanced design, the 7600 experienced disappointing sales due to its release coinciding with the 1969 economic recession in the United States and challenges related to its intricate architecture affecting reliability. It lacked full compatibility with the earlier 6000-series machines and required a newly developed, rudimentary operating system. Nevertheless, it held the title of the fastest uniprocessor from 1969 until 1976 and was widely adopted by supercomputing centers globally.

Following this, Cray engineered the CDC 8600, which integrated four processors similar to those in the 7600 within a more compact enclosure, featuring increased clock speeds and accelerated memory access. However, this dense configuration complicated cooling and maintenance efforts, resulting in significant reliability issues. Acknowledging these shortcomings, Cray determined that a complete redesign was necessary.

The STAR and the Cyber

In parallel with plans to redesign the 8600, CDC embarked on developing the CDC STAR-100 under Jim Thornton’s leadership. Unlike the multi-processor approach of the 8600, the STAR employed a vector processor architecture that pipelined arithmetic operations to enhance performance on specialized computational tasks, although it underperformed relative to the 7600 on general-purpose workloads.

Faced with limited financial resources to fund both projects simultaneously, Norris decided that CDC could not sustain concurrent development of the STAR and an updated version of the 8600. As a result, Cray departed CDC in 1972 to establish Cray Research, receiving investment support from Norris. CDC launched the STAR in 1974 as the Cyber 203; however, its actual performance did not meet initial expectations. Subsequently, Jim Thornton left CDC to found Network Systems Corporation.

By 1975, a STAR-100 was operational within a CDC service facility—the first supercomputer installed directly in a data center environment. William C. Norris orchestrated a major publicity event in collaboration with Guinness, promoting the STAR-100 as "The most powerful and fastest computer," earning recognition in the Guinness Book of World Records. This media exposure attracted significant attention and secured clients such as oil companies employing it for reservoir modeling, including projects simulating oil extraction processes for Kuwaiti fields. Coverage by Wall Street Journal contributed to winning Allis-Chalmers as a customer for hydropower turbine simulations.

Throughout the decade, CDC repackaged various systems derived from the 6600/7600 architecture into multiple price-performance segments under the CDC Cyber brand, which became their primary product line. An enhanced version of the STAR design, known as Cyber 205, delivered improved capabilities but still trailed behind Cray Research’s Cray-1 in overall speed despite supporting larger vector operations.

Although sales of STAR systems were modest, CDC continued producing follow-on models such as Cyber 200/205 that competed with offerings from Cray Research. The company also developed specialized hardware like the CDC Advanced Flexible Processor (AFP), marketed as CYBER PLUS.

Another project dubbed "Cyber 80" aimed for an introduction around 1980. This system sought to maintain backward compatibility with legacy software while introducing a new 64-bit architecture to facilitate user transition. Development extended beyond its target date before these machines were eventually marketed under different designations.

To broaden revenue streams beyond hardware sales alone, CDC also promoted services including the PLATO computer-aided learning system, which operated on Cyber platforms and pioneered early innovations in computer interfaces such as bit-mapped touchscreen terminals.

Magnetic Peripherals Inc.

Magnetic Peripherals Inc.—which later became known as Imprimis Technology—was founded in 1975 as a collaborative venture with Honeywell to produce hard disk drives. CII-Honeywell Bull took a 3% ownership share from Honeywell, and in 1983, Sperry acquired a 17% stake, resulting in an ownership distribution of CDC holding 67% and Honeywell and Sperry each owning 17%. MPI primarily functioned as an internal supplier, providing OEM products exclusively to its parent companies, while CDC sold MPI-manufactured drives under its own branding.

MPI emerged as a key competitor in the HDD industry, dominating the 14-inch disk drive OEM market segment during the late 1970s and early 1980s with its SMD (Storage Module Device) and CMD (Cartridge Module Drive) product lines. The Brynmawr facility in South Wales operated continuously, having produced one million disks and three million magnetic tapes by 1979. CDC also advanced eight-inch drives through MPI’s Oklahoma City plant; the CDC Wren series gained popularity among high-end customers despite trailing startups like Micropolis, Maxtor, and Quantum in terms of capacity and performance improvements. CDC co-developed the widely embraced Advanced Technology Attachment (ATA) interface alongside Compaq and Western Digital, targeting cost reduction for lower-performance drive models.

CDC established the Rigidyne division in Simi Valley, California, to create 3.5-inch drives based on Wren technology. Launched as the "Swift" series in 1987, these products were among the earliest high-performance 3.5-inch drives available on the market.

In September 1988, CDC merged Rigidyne and MPI under the Imprimis Technology subsidiary. The following year, Seagate Technology purchased Imprimis for $250 million in cash, issued 10.7 million Seagate shares, and provided a $50 million promissory note.

Investments

Control Data held stakes in various enterprises including computer research firm Arbitron, Commercial Credit Corporation, and Ticketron.

Commercial Credit Corporation

In 1968, Commercial Credit Corporation (CCC) faced a hostile takeover attempt by Loews Inc., which had acquired close to 10% of CCC with plans to dismantle it. To prevent this, CCC secured financing from Control Data to maintain control, resulting in CDC acquiring a diverse portfolio that even included a fleet of fishing vessels. During the volatile 1980s, Control Data began divesting assets. In 1986, Sandy Weill convinced CDC management to spin off Commercial Credit instead of liquidating it. Weill subsequently expanded Commercial Credit into what became the financial giant Citigroup. The company was renamed CitiFinancial in 1999 and later rebranded as OneMain Financial in 2011.

Ticketron

Control Data purchased a 51% ownership interest in Ticketron for $3.9 million from Cemp Investments in 1969. By 1970, Ticketron had become the exclusive computerized ticketing provider throughout the United States. Control Data increased its stake further in 1973. Ticketron provided ticketing terminals and infrastructure for parimutuel wagering and several state lottery systems including those of New York, Illinois, Pennsylvania, Delaware, Washington, and Maryland.

By the mid-1980s, Ticketron represented Control Data’s most lucrative division with revenues reaching $120 million. Despite overall company losses, CDC contemplated divesting Ticketron. In 1990, most of Ticketron’s assets were acquired by The Carlyle Group, which then sold them to competitor Ticketmaster in 1991—except for the "Telecharge" unit that was retained due to antitrust regulations.

ETA Systems, asset divestiture, and company wind-down

CDC sought to establish a foothold in the high-performance computing market, but Norris perceived the organization as lacking dynamism and innovation speed. In 1983, he launched a subsidiary, ETA Systems, with the ambition to develop a 10 GFLOPs supercomputer—approximately 40 times the speed of the Cray-1. Although the project never reached full fruition, ETA delivered some of the era’s fastest machines, producing seven liquid nitrogen-cooled models and 27 smaller air-cooled units utilizing newly developed low-heat CMOS technology. However, sales challenges led to workforce reductions in 1989 and the eventual reintegration of remaining personnel back into CDC.

Despite possessing significant technological advancements, CDC experienced substantial financial setbacks, incurring losses of $567 million in 1985 and continuing losses through 1986 amid restructuring efforts. In 1987, CDC divested its PathLab Laboratory Information System to 3M. As profitability in hardware manufacturing diminished, CDC initiated a strategic divestiture campaign in 1988, beginning with Imprimis, followed by the chip manufacturer VTC, and later shedding non-core businesses such as Ticketron.

By 1992, CDC underwent a corporate split forming two separate entities: the computer division became Control Data Systems, Inc. (CDS), while its information services unit emerged as Ceridian Corporation. CDS later acquired ICEM Technologies—developers of ICEM DDN and ICEM Surf software—and subsequently sold this business to PTC in 1998 for $40.6 million. In 1999, Syntegra, a subsidiary of BT Group, acquired CDS and integrated it into BT's Global Services division.

Ceridian transformed into a prominent provider of outsourced IT company services with a focus on human resources. The Energy Management Division, responsible for overseeing up to one-quarter of global electricity consumption, was transferred to Ceridian during the split; renamed Empros, this unit was sold to Siemens in 1993. In 1997, General Dynamics purchased Ceridian’s Computing Devices International Division—the former Government Systems Division of CDC.

In March 2001, Ceridian underwent another separation: the original company became Arbitron Inc., while human resources services and Comdata retained the Ceridian brand. The final corporate division occurred in 2013 with the establishment of Ceridian HCM Holding Inc. (human resources) and Comdata Inc. (payment solutions), marking the full divestment of CDC’s original assets.

Chronology of system launches

CDC 1604 family – models 1604, 1604-A, 1604-B, 1604-C, and 924 (a streamlined variant related to the 1604)
CDC 160 series – including 160, 160A (160-A), and 160G (160-G)
CDC 3000 series – encompassing models 3100 through 3800 (3100, 3200, 3300, 3400, 3500, 3600, 3800)
CDC 6000 series – consisting of models such as 6200, 6400, 6500, and 6700
CDC 6600
CDC 7600
CDC CYBER line – including models like Cyber17, Cyber18, Cyber71–76, Cyber170–176, Cyber203, Cyber205, Omega/480, and Cyber700
CDC STAR-100

1957 – Company founded
1959 – Release of model 1604
1960 – Introduction of model 1604-B
1961 – Launch of model 160
1962 – Debut of model 924 (a variant with a 24-bit architecture akin to the 1604)
1963 – Releases included models 160A (160-A), 1604-A, 3400 series, and 6600
1964 – Models introduced: 160G (160-G), along with the 3100, 3200, 3600 series and the powerful 6400
1965 – Arrival of models such as the updated 1604-C, 1700, plus the 3300 and 3500 series; also included were models like the IBM-compatible systems (8050 and 8090)
1966 – Launches comprised models like the robust 3800 series along with high-end units such as the Station6000 line including models like the6200 and6500
1968 – Introduction of high-performance model 7600
1969 – Release of model6700
1970 – Debut of vector processor system STAR-100
1971 – Cyber series expanded with models Cyber71 through Cyber76
1972 – Launches included models5600 and8600
1973 – New Cyber systems debuted: Cyber170 and Cyber172–175 alongside Cyber17 variants
1976 – Release of Cyber18
1977 – Introduced models such as Cyber171 and Cyber176 along with Omega/480
1979 – Expansion with Cyber203 plus Cyber720 through Cyber760 series
1980 – Introduction of advanced model Cyber205
1982 – Launches encompassed multiple advanced Cyber800 series units: Cyber815 through Cyber875
1983 – Release of high-performance supercomputer ETA10
1984 – Expanded lineup with models such as Cyber810 through Cyber860 plus high-end units like Cyber990 and CyberPlus
1987 – New additions included Cyber910, Cyber930 and high-performance Cyber995
1988 – Introduction of modelCyber960
1989 – Final releases included Cyber920 and next-generation Cyber2000

Note: The early-1980s Cyber machines from the '8xx' and '9xx' series constituted the sophisticated64-bitCyber180 family featuring virtual memory support enabled by CDC's NOS/VE operating system. While Peripheral Processors (PPs) within this range remained16-bit architectures. The official designation often followed "180/xxx" nomenclature; however shorter names such as "Cyber990" were commonly used in practice.

Peripheral Systems Group

Throughout the 1970s and 1980s, Control Data Corporation's Peripheral Systems Group functioned as a division dedicated to both hardware and software development. Its primary mission was to create and promote IBM-compatible systems software, aiming to secure a portion of the mainframe market share.

One notable offering from this group was CUPID (an acronym for "Control Data's Program for Unlike Data Set Concatenation"), tailored specifically for users of IBM's MVS operating system. Aimed at systems programmers, CUPID provided sophisticated capabilities including SysGen-like configuration options and accessible control blocks, designed to improve data handling on IBM mainframe platforms.

Film and science fiction references

Mars Needs Women (1967) – features a CDC 3400 utilized for radio transmissions and coordinating military responses against Martian spacecraft.
Colossus: The Forbin Project (1970) – opening credits display tape drives alongside early CDC machinery.
The Mad Bomber (1973) – law enforcement employs a CDC 3100 for profiling the bomber.
The Adolescence of P-1 (1977), by Thomas Ryan – centers on a young protagonist who relies heavily on Control Data computers.
The New Avengers – in episode 2-10 ("Complex", 1977), Purdey is shown operating a CDC card reader.
Mi-Sex – Computer Games (1979) music video depicts the band interacting with CDC equipment located in the North Sydney building.
Tron (1982) – a scene filmed at Lawrence Livermore National Laboratory includes appearances by a CDC 7600 and a Cray-1.
Die Hard (1988) – CDC supplied functional Cyber 180 machines along with an ETA-10 supercomputer mock-up for the film’s computer room set; these assets were managed by CDC Demonstration Services/Benchmark Lab and recorded in corporate archives post-production.
They Live (1988), directed by John Carpenter – contains an advertisement for Control Data Corporation; the credits extend "special thanks" to CDC.

External links

Control Data Corporation Records housed at the Charles Babbage Institute, University of Minnesota; these records were donated by Ceridian Corporation in 1991 and include historical timelines, product timelines, acquisition lists, and joint venture details.
Oral history interview with William Norris covering the era of ERA, its acquisition by Remington Rand, the development of the Univac File computer, leadership within Univac Division, and founding of CDC. Held at the Charles Babbage Institute, University of Minnesota.
Oral history interview with Willis K. Drake discussing Remington-Rand, Eckert-Mauchly Computer Company, ERA, and CDC’s establishment. Available through the Charles Babbage Institute, University of Minnesota.
Moderated discussion led by Neil R. Lincoln featuring eighteen CDC engineers focusing on computer architecture and design topics including CDC 1604, CDC 6600, CDC 7600, CDC 8600, CDC STAR-100, and contributions by Seymour Cray. Hosted by the Charles Babbage Institute, University of Minnesota.
Information regarding Sandy Weill’s spin-off of Commercial Credit from Control Data.
Details about the Control Data CDC 3800 Computer exhibited at the National Air and Space Museum Steven F. Udvar-Hazy Center near Washington Dulles International Airport.
Private archival collection containing historical CDC documents.
Repository of Control Data User Manuals @ Computing History.
Archive documenting usage of various CDC systems and devices from 1970 to 1985.
German archive dedicated to CDC, Cray, and other large-scale computing systems.