The Digital Group
 | |
| Industry | Electronics |
|---|---|
| Founded | ca. 1974 |
| Defunct | 1979 |
| Fate | Bankruptcy liquidation |
The Digital Group emerged as an early pioneer in microcomputer manufacturing, established around 1974 by former IBM engineers Dick Bemis and Robert Suding. Their first offering enhanced the Intel 8008-based Mark-8, followed by kit computers utilizing processors such as the Intel 8080, Motorola 6800, and MOS 6502. Significantly, they were the earliest to introduce a commercially available system based on the Zilog Z80 in 1976. Subsequently, they developed integrated designs featuring custom enclosures but ceased business operations in 1979 before these models could capture significant market share.
Inspiration
The Mark-8, launched in June 1974 through Radio-Electronics magazine, was intended as an affordable microcomputer but was hindered by intricate and unreliable hand-wired circuit boards. Despite these issues, its designer Jon Titus sold approximately 7,500 sets of plans along with several hundred pre-assembled boards.[1]
Robert Suding acquired a complete Mark-8 kit and enhanced its design by incorporating seven-segment displays, video output compatible with televisions, and keyboard input functionality. In September 1974, Hal Singer together with students from Cabrillo High School initiated the "Mark-8 User Group Newsletter." Suding engaged with subscribers based in Colorado, demonstrating his upgraded system.[2]
Formation
Dick Bemis, then at IBM Denver, visited Suding’s setup and proposed forming a business partnership involving themselves and their spouses to market plans for Suding’s refined Mark-8 design. This included schematics for a video display board and a cassette tape interface to enable mass storage. They successfully sold 575 plan sets, well exceeding their initial break-even target of 100.[2]
After the Intel 8080-based Altair 8800 debuted in January 1975, Suding considered entering this rapidly growing market segment. While Bemis favored creating expansion cards compatible with the Altair’s S-100 bus architecture, Suding championed the development of a processor-independent bus system that would support various CPUs and peripherals. This approach was intended to strengthen their competitive position amid swiftly advancing processor technologies.[2]
Suding eventually resigned from IBM after being denied a permanent engineering role following his PhD completion, dedicating his efforts entirely to The Digital Group.[2]
New processors
The company rapidly transitioned its platform from the Intel 8080 to the newly introduced Motorola 6800, designed by Chuck Peddle. After Peddle departed Motorola to create the MOS 6501, Suding quickly adapted this processor and invited Peddle’s design team to collaborate on developing what became the MOS 6502. This collaboration extended to meetings with Steve Jobs and Steve Wozniak, co-founders of Apple Computer, who sought to commercialize this design.
Shortly thereafter, Suding discovered that Federico Faggin, the architect behind both the 8008 and 8080 CPUs, had left Intel to establish Zilog and develop the Zilog Z80. The Digital Group procured several Z80 chips and easily integrated them due to their backward compatibility with the 8080 alongside enhanced features such as native 16-bit arithmetic. Suding rewrote software to exploit these capabilities and presented the new Z80-based systems at the National Computer Conference in June 1976, attracting more attention than Zilog’s own exhibition.
During this event, Suding informed Faggin about defects found in chips licensed from Texas Instruments, National Semiconductor, and AMD that impaired certain instructions on 8080 derivatives. To address this, Suding created a diagnostic tool to detect these faults and verified the Z80’s complete compatibility, thereby bolstering its appeal within the marketplace.
Expansion and collapse
By the end of 1977, the firm unveiled a streamlined case design that integrated their cards with ROM-based boot firmware, removing the front-panel switches and indicator lights typically found on rival machines. This refined approach brought the product's appearance and functionality closer to the original IBM PC than earlier systems such as the Altair or IMSAI 8080.
In 1978, the workforce expanded to over 100 employees; however, quality control (QC) became a significant challenge. To address this, Ken Jackson was appointed to oversee QC processes, resulting in the identification and rejection of defective units, which caused delays in production. Rather than improving manufacturing practices, management opted to dismiss Jackson. Following this, Suding took direct charge of quality assurance to restore operational stability.
Despite these interventions, financial strain worsened. Failures in the marketplace, including setbacks with the Sphere Computer, prompted suppliers to require payments upfront instead of extending credit, creating cash flow constraints that obstructed component acquisition. The company filed for Chapter 11 bankruptcy protection in 1979 and ultimately halted operations later that year.
External links
- History of The Digital Group
- DigiBarn Systems pictures showcasing The Digital Group, including a scan of bankruptcy auction notice
- American companies established in 1975
- American companies disestablished in 1979
- Companies based in Denver
- Computer companies established in 1975
- Computer companies disestablished in 1979
- Defunct computer companies of the United States
- Defunct computer hardware companies
- Defunct computer systems companies
- Z80-based home computers
- Companies of the United States by year of establishment