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Micral is a series of microcomputers produced by the French company Réalisation d'Études Électroniques (R2E),[1] beginning with the Micral N[2] in early 1973. The Micral N was one of the first commercially available microprocessor-based computers.

In 1986, three judges at The Computer Museum, Boston – Apple II designer and Apple Inc. co-founder Steve Wozniak, early MITS employee and PC World publisher David Bunnell, and the museum's associate director and curator Oliver Strimpel – awarded the title of "first personal computer using a microprocessor" to the 1973 Micral.[3] The Micral N was the earliest commercial, non-kit personal computer based on a microprocessor (in this case, the Intel 8008).[4]

The Computer History Museum currently says that the Micral is one of the earliest commercial, non-kit personal computers.[5] The 1971 Kenbak-1, invented before the first microprocessor, is considered to be the world's first "personal computer". That machine did not have a one-chip CPU but instead was based purely on small-scale integration TTL chips.[6]

Micral N

[edit]
Micral N
Micral N
ManufacturerRéalisation d'Études Électroniques (R2E)
TypeMicrocomputer
Release dateFebruary 1973
Introductory priceFF 8,500
CPUIntel 8008 @ 500 kHz

R2E founder André Truong Trong Thi (EFREI degree, Paris), a French immigrant from Vietnam, asked Frenchman François Gernelle to develop the Micral N computer for the Institut National de la Recherche Agronomique (INRA), starting in June 1972.[7][8][9] Alain Perrier of INRA was looking for a computer for process control in his crop evapotranspiration measurements.[10][11] The software was developed by Benchetrit. Beckmann designed the I/O boards and controllers for peripheral magnetic storage. Lacombe was responsible for the memory system, I/O high speed channel, power supply and front panel. Gernelle invented the Micral N, which was much smaller than existing minicomputers. The January 1974 Users Manual called it "the first of a new generation of mini-computer whose principal feature is its very low cost," and said, "MICRAL's principal use is in process control. It does not aim to be an universal mini-computer."[12]

The front panel of a Micral N

The computer was to be delivered in December 1972, and Gernelle, Lacombe, Benchetrit and Beckmann had to work in a cellar in Châtenay-Malabry for 18 hours a day in order to deliver the computer in time. The software, the ROM-based MIC 01 monitor and the ASMIC 01 assembler,[12] was written on an Intertechnique Multi-8 minicomputer using a cross assembler. The computer was based on an Intel 8008 microprocessor clocked at 500 kHz. It had a backplane bus, called the Pluribus with 74-pin connector. 14 boards could be plugged in a Pluribus. With two Pluribus, the Micral N could support up to 24 boards. The computer used MOS memory instead of core memory. The Micral N could support parallel and serial input/output. It had 8 levels of interrupt and a stack. The computer was programmed with punched tape, and used a teleprinter or modem for I/O. The front panel console was optional, offering customers the option of designing their own console to match a particular application.[12] It was delivered to the INRA in January 1973, and commercialized in February 1973 for FF 8,500 (about $1,750) making it a cost-effective replacement for minicomputers which augured the era of the PC.

France had produced the first microcomputer. A year would pass before the first North American microcomputer, SCELBI, was advertised in the March 1974 issue of QST, an amateur radio magazine.[13]

Indeed, INRA was originally planning to use PDP-8 computers for process control, but the Micral N could do the same for a fifth of the cost. An 8-inch floppy disk reader was added to the Micral in December 1973, following a command of the Commissariat à l'Energie Atomique. This was made possible by the pile-canal, a buffer that could accept one megabyte per second. In 1974, a keyboard and screen were fitted to the Micral computers. A hard disk (first made by CAELUS then by Diablo) became available in 1975. In 1979, the Micral 8031 D was equipped with a 5" 1/4 inches hard disk of 5 Megabytes made by Shugart.

Later models

[edit]
Micral S (1974)

Following the April 1974 introduction of the Intel 8080, R2E introduced the second and third Micral models, 8008-based at 1 MHz Micral G[14] and 8080-based at 1 MHz Micral S[15].

In November 1975, R2E signed Warner & Swasey Company as the exclusive manufacturer and marketer of the Micral line in the United States and Canada. Warner & Swasey marketed its Micral-based system for industrial data processing applications such as engineering data analysis, accounting and inventory control.[16] R2E and Warner & Swasey displayed the Micral M[17] multiple microcomputer system at the June 1976 National Computer Conference. The Micral M consists of up to eight Micral S microcomputers, each with its own local memory and sharing the common memory so the local and common memory look like one monolithic memory for each processor. The system has a distributed multiprocessor operating system R2E said was based on sharing common resources and real-time task management.[18]

Some time after the July 1976 introduction of the Zilog Z80, came the Z80-based Micral CZ. The 8080-based Micral C[19], an intelligent CRT terminal designed for word processing and automatic typesetting, was introduced in July 1977.[20] It has two Shugart SA400 minifloppy drives and a panel of system control and sense switches below the minifloppy drives. Business application language (BAL) and FORTRAN are supported. By October, R2E had set up an American subsidiary, R2E of America, in Minneapolis.[21] The Micral V Portable[22] (1978) could run FORTRAN and assembler under the Sysmic operating system, or BAL.[23] The original Sysmic operating system was renamed Prologue in 1978. Prologue was able to perform real-time multitasking, and was a multi-user system. R2E offered CP/M for the Micral C in 1979.[24]

PORTAL (1980)

The R2E Micral CCMC Portal[25] portable microcomputer made its official appearance in September 1980 at the SICOB show in Paris. It was designed and marketed by the studies and developments department of François Gernelle of the French firm R2E Micral at the request of the company CCMC specializing in payroll and accounting. The Portal was based on an Intel 8085 processor, 8-bit, clocked at 2 MHz. It weighed 12 kg (26 lb) and its dimensions were 45 cm x 45 cm x 15 cm, It provided total mobility. Its operating system was Prologue.

Later Micrals used the Intel 8088. The last Micral designed by François Gernelle was the 9020.[26] In 1981, R2E was bought by Groupe Bull. Starting with the Bull Micral 30[27], which could use both Prologue and MS-DOS, Groupe Bull transformed the Micral computers into a line of PC compatibles.[28] François Gernelle left Bull in 1983.

Legacy

[edit]

Truong's R2E sold about 90,000 units of the Micral that were mostly used in vertical applications such as highway toll booths and process control.

Litigation followed after Truong started claiming that he alone invented the first personal computer. The courts did not judge in favor of Truong, who was declared "the businessman, but not the inventor", giving in 1998 the sole claim as inventor of the first personal computer to Gernelle and the R2E engineering team.

In the mid-1970s, Philippe Kahn was a programmer for the Micral.[29][30] Kahn later headed Borland which released Turbo Pascal and Sidekick in 1983.

Paul G. Allen, the co-founder of Microsoft with Bill Gates, bought a Micral N by the auctioneer Rouillac at the Artigny Castle in France, on June 11, 2017, for his Seattle museum Living Computers: Museum + Labs.[31][32]

"Association MO5.com", a French preservation group, announced in 2023[33] that they had acquired a Micral N two years before in 2021. They are restoring it and documenting it.

Micral computer models

[edit]
Micral N (1973)

R2E series

[edit]
  • 1973 : Micral N, first microcomputer, built by François Gernelle.[34][35][2]
  • 1974 : Micral G, Intel 8008 at 1 MHz, 16K RAM[14]
  • 1974 : Micral S, Intel 8080[15]
  • 1976 : Micral M, distributed system, Intel 8080 × 8[17]
  • 1977 : Micral C, Intel 8080, 24K RAM, integrated monitor, floppy disc drive[19]
  • 1978 : Micral V, Intel 8080, 32K RAM, portable[22]

Bull series

[edit]
Micral 80-20 (1980)
Micral P2 (1981)

PC compatible series

[edit]
  • 1985 : Bull Micral 30, Intel 8088 at 4.77 MHz, PC-XT compatible (Nanoréseau[45] network machine)[27]
  • 1986 : Bull Micral 60, Intel 80286 at 6 MHz, PC-AT compatible[46]
  • 1986 : Bull Micral 35, Intel 80286 at 8 MHz[47]
  • 1987 : Bull Micral 40, Intel 80286 at 8 MHz[48]
  • 1988 : Bull Micral 45, Intel 80286 at 12 MHz[49]
  • 1988 : Bull Micral 65, Intel 80286 at 12 MHz[50]
  • 1988 : Bull Micral 75, Intel 80386 at 16 MHz[51]
  • 1988 : Bull Micral Attaché, Intel 8086 at 9.54 MHz, portable[52]
  • 1989 : Bull Micral 200, Intel 80286 at 12 MHz[53]
  • 1989 : Bull Micral 600, Intel 80386 at 25 MHz[54]
  • Unknown year : Bull Micral 500, Intel 80386 at 20 MHz, Micro Channel bus[55]

In 1989, Bull bought Zenith Data Systems, starting to release PC compatibles under the brand Zenith.

See also

[edit]

References

[edit]
[edit]
Revisions and contributorsEdit on WikipediaRead on Wikipedia

Micral

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The Micral N was the world's first commercially available, fully assembled microcomputer based on a microprocessor, developed and launched by the French engineering firm Réalisation d'Études Électroniques (R2E) in early 1973. Designed primarily for industrial process control, such as automating agronomic measurements for the Institut National de la Recherche Agronomique (INRA), it represented a breakthrough in affordable computing by leveraging the newly released Intel 8008 8-bit microprocessor operating at 500 kHz, capable of executing around 50,000 instructions per second. R2E, founded in 1970 by entrepreneur André Truong Trong Thi and engineer Paul Magneron, initiated the Micral's development in mid-1972 in response to an INRA contract for a low-cost automation system, with François Gernelle leading the technical design alongside contributors like Robert Benchetrit for software and Alain Lacombe for mechanics. The system featured a modular architecture with the proprietary 74-pin Pluribus backplane bus supporting up to 24 expansion cards, 4 KB of MOS RAM (expandable), parallel and serial I/O interfaces, eight interrupt levels, and a stack mechanism; it was programmed via punched tape and could optionally include a front-panel console for direct operation. Priced at 8,500 French francs (equivalent to about $1,700 USD or €10,000 in today's value), the Micral N was roughly one-fifth the cost of comparable minicomputers like the DEC PDP-8, making it accessible for scientific, industrial, and later business applications such as banking and insurance. The Micral's debut predated hobbyist kits like the Altair 8800 and established the term "microcomputer" in print through a June 1973 Byte magazine article describing the Micral-N model. Initial sales reached about 100 units in its first year, with total sales of the Micral series reaching approximately 90,000 units, primarily to French organizations like INRA, Société des Autoroutes du Sud, and Crédit Agricole; subsequent models evolved the line, including the faster Micral-S (1974, based on Intel 8080), the portable Micral-V (1977), and management-oriented variants like the Micral-C. R2E developed custom software such as the SYSMIC operating system and BAL business language to support these applications, emphasizing energy efficiency and modularity in line with the era's "small is beautiful" philosophy. Despite its pioneering role, the Micral remained largely confined to professional markets in France and faced competition from more consumer-oriented systems like the Apple II (1977) and IBM PC (1981), leading to R2E's acquisition by Compagnie Internationale pour l'Informatique (CII)-Honeywell-Bull in 1978, after which production ceased. Recognized by institutions like the Computer History Museum as the earliest non-kit personal computer, the Micral's legacy lies in proving the practical potential of microprocessor-based systems for real-world automation, influencing the global shift toward accessible computing and earning François Gernelle posthumous credit as its inventor following a 1998 legal resolution. In 2023, the 50th anniversary of its launch was commemorated, reaffirming its pioneering role. Today, surviving examples—fewer than a dozen are known—are rare artifacts, with one auctioned in 2017 for significant value among collectors of computing history.

Development

Founding of R2E

Réalisation d'Études Électroniques (R2E) was founded in 1970 in Orsay, France, by engineers André Truong Trong Thi and Paul Magneron, building on their prior expertise at Intertechnique, a company specializing in scientific instrumentation. Truong, a Vietnamese-born immigrant who had studied at the École Française d'Électronique et de Radiolélectricité (EFREI) in Paris, had gained experience in electronics at Schlumberger before moving to Intertechnique, where he focused on automation systems. Magneron, as director of sales at Intertechnique, contributed commercial insight to the new venture, which aimed to provide tailored electronic solutions in a rapidly evolving field. From its inception, R2E concentrated on industrial electronics, particularly custom systems for instrumentation and process automation in sectors like medical and nuclear energy applications. This focus aligned with the era's "small is beautiful" philosophy, popularized by E.F. Schumacher's ideas on appropriate technology and miniaturization, which emphasized efficient, cost-effective designs over large-scale systems. The company's approach was further influenced by emerging microprocessor technology, such as Intel's 4004 introduced in 1971, which promised programmable logic at reduced sizes and costs. François Gernelle, a self-taught engineer with a background in miniaturization and process control from his time at Intertechnique's systems team, joined R2E in 1971 as a lead engineer. His expertise in developing compact electronic controls for industrial applications complemented Truong's vision, enabling R2E to produce generic products like printers and magnetic-tape systems alongside bespoke automation solutions. Initial financial backing came through connections to Intertechnique, providing resources for R2E's early operations and contracts in electronic automation. These early projects, including custom instrumentation for research institutions, laid the groundwork for R2E's pivot toward microprocessor-based computing by demonstrating the viability of integrated, programmable electronics in practical settings.

Design of the Micral N

The development of the Micral N began in 1972 at Réalisation d'Études Électroniques (R2E), motivated by a contract signed in July with the Institut National de la Recherche Agronomique (INRA) to create a low-cost system for automating agricultural data processing and environmental control in greenhouses. The project, led by engineer François Gernelle, aimed to deliver a prototype by December 1972, but intensive work in R2E's facilities at Châtenay-Malabry extended completion to January 1973, when the system was successfully installed at INRA's Versailles facility. At the core of the Micral N's design was the Intel 8008 microprocessor, an 8-bit chip clocked at 500 kHz and capable of executing approximately 50,000 instructions per second, selected by Gernelle for its greater availability, cost-effectiveness, and enhanced capabilities compared to the earlier 4-bit Intel 4004. This choice enabled the Micral N to perform process control tasks more efficiently than the 4004 while remaining far more affordable than minicomputers like the DEC PDP-8, which operated at speeds up to 350,000 instructions per second but cost significantly more. To support robust input/output operations essential for industrial applications, Gernelle invented the modular Pluribus bus architecture—a backplane with 11 connectors allowing up to 24 expansion boards—and the Stack-Channel buffer, which optimized data handling through stacked I/O channels for real-time process monitoring. These innovations culminated in a patent filing on February 5, 1973, by François Gernelle on behalf of R2E (French patent FR2216883), covering the overall system design with its emphasis on modularity, expandability, and low-cost construction using off-the-shelf components. The design targeted an initial price of around 8,500 French francs (equivalent to approximately $1,750 USD at the time), intentionally undercutting the DEC PDP-8's price of about 45,000 francs to make microprocessor-based computing accessible for non-military and non-scientific uses.

Commercialization and Acquisition

The Micral N made its public debut at the 1973 Sicob trade show in April, initiating the first commercial sales of R2E's microcomputer and positioning it as an affordable tool for professional use at a price of 8,450 francs. This launch followed the initial prototype delivery to the French National Institute for Agricultural Research (INRA) in January 1973, transitioning R2E from custom engineering projects to broader market offerings. R2E expanded sales from bespoke orders to professional sectors, primarily targeting industrial automation applications in France and Europe, where the Micral N served as a cost-effective controller for processes in agriculture, energy, and manufacturing. By the end of 1973, approximately 100 units had been sold, with production scaling through modular designs that supported variants like the Gessix 1000, leading to an estimated several hundred units delivered by 1975 as demand grew among small and medium-sized enterprises for automation and early management computing tasks. In the mid-1970s, R2E encountered significant financial challenges, including rising development costs and intensifying competition from U.S. microprocessor suppliers and emerging minicomputer firms, which strained the company's resources despite steady sales growth. These pressures culminated in 1978, when CII-Honeywell-Bull acquired 90% of R2E, integrating the Micral line into its larger portfolio and redirecting efforts toward standardized computing products for industrial and office environments.

Models

R2E Series

The R2E series encompassed the initial lineup of Micral microcomputers produced by Réalisation d'Études Électroniques (R2E) between 1973 and 1977, marking pioneering efforts in affordable, modular computing for industrial and scientific domains. These models evolved from basic process control systems to more versatile configurations, all built around Intel's early 8-bit microprocessors and a proprietary Pluribus bus for expandability. Designed by engineer François Gernelle under the direction of company founders André Truong Trong Thi and Paul Magneron, the series prioritized low power consumption, real-time operation, and integration with peripherals like teleprinters and modems. The foundational Micral N, introduced in early 1973, served as the world's first commercially available, fully assembled microcomputer based on a microprocessor. It utilized an Intel 8008 processor clocked at 500 kHz, with RAM expandable from 4 KB to 16 KB via modular cards, and supported up to 24 expansion boards on its 74-pin backplane bus. Targeted at process control in scientific instrumentation and automation—such as applications for the French National Institute for Agricultural Research (INRA)—the Micral N was priced at 8,500 francs (approximately $1,750) and featured 8 interrupt levels, stack processing, and parallel/serial I/O interfaces. Initial software included a ROM-based MIC 01 monitor and ASMIC 01 assembler, with programming via punched tape; around 100 units were sold in its first year. In 1974, R2E released the Micral G as an upgraded variant of the N, boosting the Intel 8008 to 1 MHz for roughly double the performance while standardizing on 16 KB RAM. This model was offered at 10,000 francs to appeal to similar process-oriented users. Later that year, the Micral S marked a significant leap by adopting the Intel 8080 microprocessor, which delivered six times the speed of the 8008 at 1 MHz, with backward software compatibility and retained modularity for broader industrial applications; pricing remained comparable to the G at around 10,000 francs. The Micral M, launched in 1975, introduced multi-processor functionality to handle complex parallel tasks, supporting 1 to 8 Intel 8080 CPUs in a federal architecture that distributed processing across shared memory and enhanced peripherals for real-time, multi-user environments. By 1977, R2E expanded into management and mobility with the Micral C, an Intel 8080-based system with 24 KB RAM, an integrated keyboard, CRT screen, and dual 5.25-inch floppy drives, oriented toward office automation for small businesses. A Z80-based variant, the Micral CZ, was also released that year. Complementing it, the Micral V offered portability in a "suitcase" form factor, featuring an Intel 8080 at 1 MHz, 32 KB standard RAM (expandable to 64 KB), an ASCII keyboard, Panaplex display, Shugart floppy drive, and printer port for field-based management applications. Overall R2E production across these models is estimated at several hundred units, underscoring their niche but influential role in early microcomputing.

Bull Series

Following the 1978 acquisition of a 90% stake in R2E by CII-Honeywell-Bull, the Micral line was restructured under Bull's oversight, integrating its microcomputer technology into the company's broader minicomputer offerings to support industrial and professional applications. This transition enabled Bull to refine and expand the series, launching models under the Bull-Micral branding that emphasized robust hardware for specialized environments. The series 90, introduced in 1981, built on earlier Micral designs with enhancements to input/output interfaces, facilitating integration into factory automation systems. A key model in this era was the Bull Micral 30, released in 1985 as the company's first IBM PC XT-compatible system. It featured an Intel 8088 processor operating at 4.77 MHz, configurable RAM from 128 KB to 384 KB (expandable to 640 KB), and an optional 10 MB hard drive alongside 360 KB floppy drives, positioning it for small business computing tasks such as data management and networked operations. The system included eight ISA expansion slots for peripherals, supporting modular upgrades like graphics cards and controllers to enhance connectivity in professional settings. Bull's Micral models under this series prioritized reliability and adaptability for vertical markets, including process monitoring and automation, through durable construction and flexible I/O configurations. Production at Bull's Villeneuve-d'Ascq facility ramped up significantly, delivering 29,000 units in 1985 alone—four times the prior year's volume—with revenues surpassing 1 billion francs, contributing to the line's sustained commercial viability into the mid-1980s.

PC-Compatible Series

In the mid-1980s, under Groupe Bull's ownership, the Micral line underwent a significant transformation to align with emerging IBM PC standards, marking a shift from proprietary architectures to broader market compatibility. This evolution began around 1983 with models like the Micral 90-50 and accelerated by 1985 with the introduction of MS-DOS support alongside the legacy Prologue operating system, enabling the use of the expanding PC software ecosystem. The change reflected Bull's strategy to compete in the burgeoning personal computer market while retaining the Micral's reputation for reliability in professional environments. The Bull Micral 50/60 series, launched between 1986 and 1988, exemplified this PC-compatible phase. The Micral 60, introduced in 1986 as a direct competitor to the IBM PC AT, featured an Intel 80286 processor clocked at 6 or 8 MHz, with an optional 80287 math coprocessor, 512 KB of RAM expandable to 640 KB or more, and EGA graphics support via a 12-inch color or 14-inch monochrome monitor. It included 5.25-inch 1.2 MB floppy drives, hard disks of 20 or 40 MB, and ran MS-DOS 3.1 for single-user applications or Prologue Multivue for multi-user setups supporting up to four tasks per user. Earlier in the series, the Micral 90-50 utilized an Intel 8086 at 8 MHz with 256 KB RAM, bridging the transition to full PC XT/AT compatibility. These systems prioritized modular expansion and networking via Bull's SPR cards, allowing integration into office environments. These PC-compatible Micrals found primary applications in enterprise settings, including networked office systems for task management and data processing, as well as upgrades for legacy industrial installations where their robust design supported process control tasks. Prologue's multi-user capabilities enabled shared access in small workgroups, while MS-DOS compatibility facilitated the adoption of standard business software. Sales of the Micral line peaked in this era, with 29,000 units delivered in 1985 alone, representing about half the volume of IBM PC sales that year and underscoring their commercial viability in Europe. The PC-compatible series concluded around 1990, with the final model, the Micral 600 featuring an 80386 processor at 25 MHz, marking the end of the line as Bull pivoted toward advanced workstations and servers like the DPX series. This phase contributed substantially to the overall Micral legacy, though exact total unit figures remain debated among historians.

Technical Features

Hardware Architecture

The Micral series employed a proprietary backplane bus called the Pluribus, consisting of a 74-pin modular connector that facilitated expansion through up to 11 plug-in cards for the CPU, memory, and I/O components. This design enabled modular construction, with the possibility of cascading two Pluribus buses to support up to 22 cards in more advanced configurations, promoting flexibility for industrial applications without relying on standardized buses like S-100. The bus architecture emphasized reliability in harsh environments, using a cast aluminum frame to mount the backplane and shield against electromagnetic interference. Processor evolution in the Micral lineup began with the 8-bit Intel 8008 in the inaugural Micral N model, operating at a clock speed of 500 kHz to handle basic process control tasks. Subsequent R2E models, such as the Micral S, upgraded to the Intel 8080, an improved 8-bit processor capable of 1 MHz, enhancing instruction throughput and interrupt handling with eight levels of priority. By the Bull-acquired era, the series progressed to 16-bit processors like the Intel 8086 and 8088, with later models using 32-bit processors such as the Intel 80386 at speeds up to 20 MHz while maintaining backward compatibility with earlier software. These shifts reflected the rapid advancement in Intel's microprocessor lineup, allowing the Micral to scale from simple automation to broader computing needs. Memory systems in the Micral started with a base configuration of 2-4 KB of RAM in the Micral N, expandable via dedicated cards to a maximum of 16 KB due to the 8008's addressing limits, utilizing static RAM (SRAM) chips such as Intel 2102 for cost-effective density. Custom controllers managed error checking, ensuring stable operation in dynamic environments; later R2E models extended capacity to 64 KB with segmented addressing on 8080-based systems, incorporating parity bits for data integrity. This approach prioritized industrial robustness over high capacity, with RAM cards featuring identical interfaces for seamless stacking on the Pluribus bus. The chassis design emphasized compactness and durability for deployment in process control settings, with the Micral N housed in a metal enclosure measuring approximately 45 cm × 30 cm × 20 cm and weighing around 12 kg. Power supplies were engineered for reliability, delivering 100-200 W to support multiple expansion cards while operating on standard 220 V AC inputs, incorporating filtering to mitigate noise in industrial power lines. Ventilation and shielding in the aluminum frame protected components from dust and vibration, contributing to the system's reputation for long-term stability. Input/output capabilities centered on the Stack-Channel board, a versatile buffering mechanism for real-time data acquisition that operated in two modes: stack mode for last-in, first-out (LIFO) temporary storage during interrupts, and channel mode for high-speed sequential transfer to peripherals like sensors or actuators. Standard interfaces included serial ports for asynchronous communication (e.g., RS-232 compatible) and parallel ports for direct device attachment, with eight interrupt levels to prioritize I/O events. Later models added optional 8-inch floppy drives for mass storage, connected via dedicated controllers on the Pluribus, enabling persistent data logging without external dependencies.

Software and Peripherals

The Micral's software ecosystem was built around custom operating systems and development tools tailored for its Intel 8008 and later 8080 processors, emphasizing real-time control and industrial applications. Introduced in 1975, SYSMIC (System Micral) served as the primary operating system for early R2E models, functioning as a multitasking, multi-user, and multi-station real-time OS designed for industrial automation and management computing tasks. It featured robust input/output management for interrupt handling and modular architecture to support efficient peripheral integration, enabling concurrent operations across multiple stations. SYSMIC was later renamed Prologue following R2E's acquisition by Groupe Bull in 1978, but it retained its core real-time capabilities for the Micral series. Programming for the Micral relied heavily on BAL (Business Application Language), a proprietary assembly language optimized for the 8008 and 8080 microprocessors. BAL included integrated tools for debugging, editing, and linking, allowing developers to create low-level code directly suited to the system's constrained resources. Complementary languages like BASIC and FORTRAN were also supported under SYSMIC, facilitating higher-level development for control applications. These tools prioritized embedded programming, with cross-compilers available on larger host systems to generate efficient binaries for Micral's limited memory and processing environments. Early Micral models incorporated basic peripherals for data storage and interaction, including magnetic tapes for program and data handling, alongside keyboards, screens, and printers for user interface and output. During the Bull era, storage evolved to include 8-inch floppy disk units like the M2310. CRT terminals provided console access, and analog modules extended I/O for specialized industrial peripherals. With the shift to PC-compatible models in the 1980s, such as the Bull Micral 30, the software transitioned to MS-DOS, incorporating drivers to maintain compatibility with legacy Micral hardware like floppy drives and terminals.

Applications and Impact

Early Uses

The first practical deployment of the Micral occurred in January 1973, when a prototype was delivered to the Institut National de la Recherche Agronomique (INRA), France's national agricultural research institute, for automating data collection in agronomic studies. This system processed real-time sensor data to calculate evapotranspiration rates, enabling precise monitoring of soil evaporation and plant transpiration for water balance assessments in agricultural fields. Such applications marked the Micral's initial role in research-oriented automation, where its compact design facilitated on-site integration with environmental sensors. In industrial settings, the Micral found early adoption for control systems, particularly in French highway toll booths starting from 1973, where it handled transaction logging and basic traffic management. By 1975, upgraded models like the Micral S and M were deployed in these environments to enhance real-time data processing for automated fee collection and vehicle flow optimization. Similarly, in manufacturing, Micral systems supported process automation in factories through multi-processor configurations that allowed distributed control of operations. The Micral also entered professional niches with the introduction of the Micral C in 1977, which facilitated early office automation trials for data entry and basic management tasks in small businesses. Equipped with a keyboard and display, it targeted small and medium-sized enterprises for administrative computing needs. However, these early uses were confined to business-to-business (B2B) markets, with no penetration into consumer segments due to the system's focus on customized industrial solutions and failed attempts to expand into the U.S. market. High customization requirements further limited broader adoption, as each deployment often involved tailored hardware and software adaptations.

Commercial Success

The Micral series achieved modest initial commercial success as an affordable alternative to more expensive minicomputers like the DEC PDP-8, which cost around 45,000 francs, while the Micral N was priced at 8,500 francs in 1973. Early sales were limited, with approximately 100 units of the Micral N sold in its first year (1973), primarily to professional sectors such as industrial automation and scientific research in France. By 1978, cumulative sales across R2E's Micral variants remained under 2,000 units, reflecting the challenges of entering a nascent market dominated by U.S. innovations. Following the 1978 acquisition of 90% of R2E by CII-Honeywell-Bull, the Micral line experienced significant growth, rebranded as Bull Micral and expanded into PC-compatible models. Sales scaled rapidly under Bull's resources, reaching nearly 90,000 units by 1981, with continued production through the 1980s contributing to the total figure across variants. This trajectory positioned the Micral as a key player in France's industrial microcomputer sector, targeting small and medium enterprises with modular systems for management and process control. The economic impact was substantial for R2E, transforming it from a small startup into a viable entity attractive for acquisition, while bolstering Bull's entry into affordable computing strategies. Export efforts were constrained, primarily limited to European markets through partnerships with Bull and earlier collaborations like Honeywell and GE, including demonstrations in Germany and Italy but avoiding significant U.S. penetration due to the dominance of ecosystems around the Altair 8800 and later Apple products. Financial strains from 1975 to 1978, exacerbated by low early sales and intense competition from inexpensive U.S. hobbyist kits, ultimately necessitated the Bull acquisition to stabilize operations. Despite these hurdles, the Micral's commercial evolution underscored its role in democratizing microcomputing for industrial applications in Europe.

Legacy

Recognition and Disputes

In 1986, The Computer Museum in Boston awarded the Micral a prize as the first commercially available microprocessor-based personal computer during its Early Model Personal Computer Contest, with judges including Steve Wozniak, David Bunnell, and Oliver Strimpel evaluating entries from 13 countries. This recognition highlighted the Micral's pioneering role, distinguishing it from earlier kits by its fully assembled design and targeted applications in process control. A significant dispute arose over the Micral's invention, leading to litigation between François Gernelle, the lead engineer who designed its architecture, and R2E founder André Truong, who claimed primary credit. In November 1998, after four years of proceedings initiated in 1994, the Cour d'appel de Versailles ruled in favor of Gernelle and the R2E engineering team, affirming their status as the inventors of the microcomputer. The Micral's status as the "first personal computer" has sparked ongoing debates among historians, particularly in comparison to the 1975 Altair 8800, which is often credited as the spark for the hobbyist movement but required user assembly unlike the ready-to-use Micral. Proponents emphasize the Micral's 1973 commercial launch and application-specific completeness as key differentiators, a view reinforced in formal recognitions. Marking its 50th anniversary in 2023, French institutions celebrated the Micral's contributions to European computing history through events organized by tech associations, including a dedicated workshop at Inria's Rocquencourt site during European Heritage Days. These commemorations underscored its legacy as the world's first commercial microcomputer, predating widespread U.S. innovations. Efforts toward formal IEEE Milestone recognition began around 2023, with a proposal submitted by 2025 (Docket #2025-27) to honor the Micral N for pioneering commercial microcomputers using the Intel 8008 microprocessor, currently under review by the IEEE History Committee.

Preservation Efforts

In 2021, the French preservation group Association MO5.com acquired an original Micral N unit, marking a significant step in safeguarding one of the earliest microcomputers. This acquisition, supported by a crowdfunding campaign, enabled the association to begin restoration work aimed at returning the machine to operational status for public display and software emulation projects. In 2024, the project received the Tony Sale Award from the Computer Conservation Society for outstanding achievement in computer conservation and restoration. The effort involves a dedicated team of volunteers and experts utilizing advanced diagnostic tools to assess and repair the hardware, with progress documented through detailed analyses of its electronic boards and ROM contents. Documentation initiatives have further bolstered preservation by digitizing key resources. Following the submission, a Milestone plaque is planned to recognize the Micral N as the world's first commercial microcomputer and will be installed at the Conservatoire National des Arts et Métiers (Cnam) in Paris, where a unit is also housed in the museum collection. Complementing this, digital archives hosted by Bitsavers and the Internet Archive provide scanned copies of original manuals and schematics, such as the 1974 Micral N Users Manual, facilitating research and replication efforts worldwide. Micral systems have appeared in various exhibitions to educate the public on early computing history. The Computer History Museum features the Micral in its online Revolution exhibit on personal computers, highlighting its role as a pioneering fully assembled system based on the Intel 8008 microprocessor. In France, Association MO5.com has showcased restored and replica units at tech fairs and events, including demonstrations of working models to illustrate microcomputer functionality. Preservation faces substantial challenges due to the Micral's rarity, with fewer than a dozen units estimated to survive as of 2025, many in private collections or deteriorated condition. Component obsolescence poses a major hurdle, as vintage integrated circuits and peripherals from the 1970s are no longer manufactured, prompting restorers to source replacements from salvaged equipment or pursue reverse-engineering. Efforts to recreate custom integrated circuits, where needed for full functionality, involve collaboration with electronics specialists to fabricate equivalents using modern fabrication techniques while preserving original designs. Beyond display, preserved Micral units play an educational role in computing history curricula. Association MO5.com integrates the restored Micral N into workshops and courses, using it to demonstrate foundational microcomputer architecture and the transition from minicomputers to personal systems. This hands-on approach helps students and researchers grasp the innovative engineering behind early microprocessor-based machines like the original Micral N.

References

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