Ferranti Orion

The Orion was a mid-range mainframe computer introduced by Ferranti in 1959 that was intended to be their primary offering during the early 1960s, complementing their high-end Atlas and various process control systems like the Argus. The Orion included built-in multitasking support, being perhaps the first commercial machine to do so, and was based on a new type of logic circuit known as "Neuron". Performance of the system was much less than expected and the Orion was a business disaster, selling only about eleven machines. The Orion II, originally a backup project, was also offered, selling about five systems. [ [http://ferranti-orion.co.uk/ Orion Programmers' Reference Manual] ] The failure of the Orion project was one of the primary reasons Ferranti left the computer business only a few years later.

Orion I

The Orion project was based on a new type of logic circuit known as "Neuron". Although details in the existing literature are scarce, it appears that the Neuron was an application of magnetic amplifiers, a solid state technology that was at one time a serious competitor to transistors in the effort to replace vacuum tubes in computers. Neuron used multiple inputs per switch, as opposed to a more common circuit where every switching unit (typically a transistor) has a single input. This allowed each amplifier to be used in several different circuits, as long as they were not in use at the same time. For instance, a particular amplifier might be able to be used in the addition, subtraction and multiplication circuits, reducing the overall component count.

The Ferranti Sirius computer was originally intended as a test-bed for the Neuron, and worked well, but the technology did not scale reliably to the much greater demands of the Orion.

Getting Neuron to work properly appears to be the reason for the Orion's low speed, and its later than expected delivery. Orion was eventually delivered, but was over a year late and unit cost was more than expected, limiting its sales. Between 1962 and 1964 the Computing Division lost $7.5 million, largely as a result of the Orion. [ [http://books.google.com/books?id=CrzgS5SoMzcC&pg=PA254&lpg=PA254&dq=ferranti+packard+orion&source=web&ots=MGvLzpy_jf&sig=-2WMdc9WRdKI0z481G7SSqVaZZo Ferranti-Packard: Pioneers in Canadian Electrical Manufacturing] , pp. 254]

The basic Orion machine included 4,096 48-bit words of core memory, which could be expanded to 16,384 words. [ [http://archive.computerhistory.org/resources/text/Ferranti/Ferranti.ORION.1960.102646248.pdf Ferranti Orion Computer System] - sales brochure] Each word could be organized as eight 6-bit characters, a single 48-bit decimal number (14 digits in base 10), or a single floating-point number with 40-bits of "fraction" and an 8-bit exponent. The core memory was backed by one or two magnetic drums with 16k words each. Various offline input/output included magnetic disks, tape drives, punched cards, punched tape and printers. The system automatically switched programs during the time spent waiting for the end of an I/O operation.

Most of the Orion's instruction set used a three-address form, with sixty-four 48-bit accumulators. Each program had its own private accumulator set, but the rest of the addresses were absolute against the entire "store", and could be modified for indexing arrays and similar tasks. A basic three-address instruction took a minimum of 64 μS, a two-address one 48 μS, and any index modifications on the addresses added 16 μS per modified address. Multiplication took from 156 to 172 μS, and division anywhere from 564 to 1,112 μS, although the average time was 574 μS.

Orion II

During the Orion's gestation it appeared there was a real possibility the new system might not work at all, and management started a parallel project, Orion II, as a backup. Orion II was similar in logical terms to the Orion I, but used the NOR-transistor based circuitry developed by Ferranti-Packard in Canada as part of their ReserVec project, which was now being used on a general-purpose computer, then known as the F.P.60. For some time during 1961-62 several members of the Canadian team worked in the UK on the Orion II, first at the Manchester lab where the Orion (I) was being built, and later at Ferranti's new research facility in Bracknell. [ [http://ieee.ca/millennium/fp6000/fp6000_datar.html From DATAR To The FP-6000 Computer] ]

The first Orion II was delivered to Prudential on 1 December 1964, running at about five times the speed of the Orion I. However by this point in time Ferranti had already decided to leave the business computer market, largely due to the problems with the Orion I, and had sold most of the computing division to ICT. Only five systems were delivered, all of them ordered before the division was sold off.

Ironically, ICT based their 1960s computer lineup not on the 48-bit Orion II, but the 24-bit Ferranti-Packard 6000, the Canadian computer formerly known as the F.P.60, whose circuitry had been used for the Orion II. Only a small number of FP-6000s were sold in Canada, but the design was passed onto ICT when Ferranti sold them the computer division. The basic FP-6000s design was developed into the ICT 1900 series, which was very successful during the 1960s and 1970s.

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