Digico (computer company)

Digico Limited

Trade name	digico, DIGICO Computers
Industry	Computer hardware
Founded	1965
Founders	Keith Trickett and Avo Hiiemae
Defunct	January 30, 1984 (1984-01-30) (as independent company)
Fate	acquired from the receiver by Centreway Industries plc
Headquarters	Stevenage , United Kingdom
Key people	Eric Lubbock (chairman)
Products	data loggers, minicomputers, microcomputers

Digico was a British computer company founded in 1965. Digico was best known for its 16-bit minicomputer series, the Micro 16. Later Digico started manufacturing a networked CP/M based microcomputer system with business software options, named Digico Prince.

Digico was founded in 1965 by Keith Trickett and Avo Hiiemae, two ex-ICL electronics engineers. Former MP Eric Lubbock was chairman from 1969 to 1983.¹ The company was based in Letchworth initially, moving to a new factory in Stevenage in 1973² and employing about 90 staff.³

Digico's first product was a laboratory data-logging and spectrum analyser hardware system named DIGIAC. A prototype had been developed before Digico was formed, by the founders in a garage, so became an immediate source of income.¹ Digico soon developed a 16-bit minicomputer series, the Micro 16, for which it was best known for.⁴

In 1974 Digico had a turnover of over £1 million (equivalent to £9 million in 2025) and in 1977 well over £1 million.⁵⁶

Spanverne Investments raised a large private capital investment into Digico in 1981, while the new Prince product was being developed.⁷

In October 1982, Digico announced it would close its Stevenage factory with the loss of 130 jobs within six months. This was part of a rationalisation plan to concentrate manufacturing at its large Leeds site. It would retain its Letchworth site primarily as a south England office.⁸

On 1 February 1984, the Financial Times reported that after a weekend of failed negotiation between British computer company Optim and Midland Bank, Digico went into receivership on 30 January 1984. Digico owed more that £400,000 to Midland Bank and over £1 million to other creditors. In 1983 debts to the bank had reached about £1.4 million, but were reduced when Optim bought Digico's maintenance contracts with about 1,500 customers for £750,000 in autumn 1983. The company had lost £2.5 million over the previous two years on an annual turnover of about £4 million (equivalent to £13,600,000 in 2025), and had closed its Letchworth factory retaining about 50 employees.⁹

Digico was acquired from the receiver by Centreway Industries plc for £265,000 in March 1984 and merged into its computer group.¹⁰

Digico quickly started developing a general purpose 16-bit minicomputer, the Micro 16, which became available in 1966. Digico was assisted by the Ministry of Technology and the National Research Development Corporation in this development.¹²¹¹ The first version produced was the Digico Micro 16S (1968), followed by the 16P (1970), then the 16V in 1972.⁴¹²

The Digico Micro 16V had a standard memory of 4k words with 950 nano second cycle time, expandable to 64k words, and able to support up to 64 external interfaces. It had an optional microprogrammed floating-point unit.¹³ The Micro 16V was supported by a simple and flexibly sized executive that could optionally support multiprogramming, disc files and teletypes.¹⁴ The Micro 16V used semiconductor memory, rather than magnetic-core memory as in the previous models.¹⁵

The instruction set architecture is single accumulator based with instructions generally having a consistent 12-bit address field. A direct address thus limits memory size to 4k (4096) words in the current selected memory region, named a "stack". Three instructions (load, store, add) permit indirect addressing where the direct address contains the 16-bit address of the operand. A carry register supports multi-word arithmetic; there is no integer multiply or divide instruction. One instruction uses the address field to specify a variety of non-addressing sub-instructions such as shift, carry manipulation and input-output. Floating-point arithmetic is handled by software or an optional floating-point unit with its own registers that can work in 32, 48 or 80-bit modes.¹³

The Micro 16 sold primarily into the data logging market until 1969, when it expanded into areas like process control, stock control and front-end processors for the ICL 1900 mainframe.¹¹⁶

In 1978 the Digico Micro 16E stackable minicomputer, which was well suited to an office environment, won a Design Council Award for Engineering Products.¹⁷¹⁸

In 1981,¹⁹ Digico started manufacturing a CP/M based microcomputer with business software options, named Digico Prince, with a claimed unique seven year maintenance guarantee.²⁰²¹

A more sophisticated multi-user Digico Prince II system was also available. The Digico 3800 user terminal had three Zilog Z80A processors, 64 kilo-bytes of memory and optionally two floppy disk drives. Up to three Digico 3800s could be connected to a 3810, 3820 or 3830 master workstation with a shared 5 MB Winchester disk drive. Up to 32 of these clusters could further be connected locally or remotely to a Digico 7800 server based on a Digico Micro 16E, providing more shared disc capacity and remote access to IBM, ICL and Honeywell mainframe computers.²²