GEC 4000 series
Encyclopedia
16-bit
-16-bit architecture:The HP BPC, introduced in 1975, was the world's first 16-bit microprocessor. Prominent 16-bit processors include the PDP-11, Intel 8086, Intel 80286 and the WDC 65C816. The Intel 8088 was program-compatible with the Intel 8086, and was 16-bit in that its registers were 16...
/32-bit
32-bit
The range of integer values that can be stored in 32 bits is 0 through 4,294,967,295. Hence, a processor with 32-bit memory addresses can directly access 4 GB of byte-addressable memory....
minicomputers produced by GEC Computers Ltd. of the UK
United Kingdom
The United Kingdom of Great Britain and Northern IrelandIn the United Kingdom and Dependencies, other languages have been officially recognised as legitimate autochthonous languages under the European Charter for Regional or Minority Languages...
during the 1970s, 1980s and early 1990s.
History
GEC ComputersGEC Computers
GEC Computers Limited was the computer manufacturing company under the GEC holding company.-History:Starting life as Elliott Automation, the data processing computer products were transferred to ICT/ICL and non-computing products to English Electric as part of a reorganisation of the parent company...
started as Elliott Automation
Elliott Brothers (computer company)
-Elliott Brothers Ltd:Elliott Brothers Ltd was an early computer company of the 1950s–60s in the United Kingdom, tracing its descent from a firm of instrument makers founded by William Elliott in London around 1804. The research laboratories were based at Borehamwood, originally set up in...
with the then aging Elliott 900 series, and needed to develop a new range of systems. Three ranges were identified, known internally as Alpha, Beta, and Gamma. Alpha appeared first and became the GEC 2050
GEC 2050
The GEC 2050 was an 8-bit minicomputer produced during the 1970s, initially by Marconi Elliott Computer Systems of the UK, before the company renamed itself GEC Computers Limited...
8-bit minicomputer. Beta followed and became the GEC 4080. Gamma was never developed, so a few of its enhanced features were consequently pulled back into the GEC 4080. The principal designer of the GEC 4080 was Dr. Michael Melliar-Smith and the principal designer of the GEC 4060 and GEC 4090 was Peter Mackley.
The 4000 series systems were developed and manufactured in the UK at GEC Computers Borehamwood
Borehamwood
-Film industry:Since the 1920s, the town has been home to several film studios and many shots of its streets are included in final cuts of 20th century British films. This earned it the nickname of the "British Hollywood"...
offices in Elstree Way. Development and manufacture transferred to GEC Computers new Dunstable
Dunstable
Dunstable is a market town and civil parish located in Bedfordshire, England. It lies on the eastward tail spurs of the Chiltern Hills, 30 miles north of London. These geographical features form several steep chalk escarpments most noticeable when approaching Dunstable from the north.-Etymology:In...
factories in Woodside Estate, Dunstable in the late 1970s. In 1979, GEC Computers was awarded the Queen's Award for Technical Achievement
Queen's Awards for Enterprise
The Queen's Awards for Enterprise is an awards programme for British businesses and other organizations who excel at international trade, innovation or sustainable development. They are the highest official UK awards for British businesses...
for the development of the 4000 series, particularly Nucleus. By 1991, the number of systems manufactured was falling off, and manufacture was transferred to GPT
GPT
-Biology:* Alanine transaminase or Glutamate Pyruvate Transaminase, an enzyme useful in a blood test* Xanthine-guanine phosphoribosyl-transferase, an enzyme in purine metabolism-Technology:...
's Beeston, Nottinghamshire
Beeston, Nottinghamshire
Beeston is a town in Nottinghamshire, England. It is southwest of Nottingham city centre. Although typically regarded as a suburb of the City of Nottingham, and officially designated as part of the Nottingham Urban Area, for local government purposes it is in the borough of Broxtowe, lying outside...
factory, and development returned to Borehamwood. The last systems were manufactured around 1995, although there are still a few GEC 4220 systems operating in 2009 with maintenance provided by Telent.
Nucleus
The GEC 4000 series hardwareComputer hardware
Personal computer hardware are component devices which are typically installed into or peripheral to a computer case to create a personal computer upon which system software is installed including a firmware interface such as a BIOS and an operating system which supports application software that...
and firmware
Firmware
In electronic systems and computing, firmware is a term often used to denote the fixed, usually rather small, programs and/or data structures that internally control various electronic devices...
included a pioneering facility known as Nucleus. Nucleus implements a number of features which are more usually implemented within an operating system
Operating system
An operating system is a set of programs that manage computer hardware resources and provide common services for application software. The operating system is the most important type of system software in a computer system...
kernel
Kernel (computing)
In computing, the kernel is the main component of most computer operating systems; it is a bridge between applications and the actual data processing done at the hardware level. The kernel's responsibilities include managing the system's resources...
, and consequently operating systems running on GEC 4000 series systems do not need to directly provide these features themselves. Nucleus firmware cannot be reprogrammed by any code running on the system, and this made the systems particularly attractive to a number of security applications.
Nucleus performs:
- processProcess (computing)In computing, a process is an instance of a computer program that is being executed. It contains the program code and its current activity. Depending on the operating system , a process may be made up of multiple threads of execution that execute instructions concurrently.A computer program is a...
scheduling - context switching
- efficient semaphoreSemaphore (programming)In computer science, a semaphore is a variable or abstract data type that provides a simple but useful abstraction for controlling access by multiple processes to a common resource in a parallel programming environment....
s - asynchronous message passingMessage passingMessage passing in computer science is a form of communication used in parallel computing, object-oriented programming, and interprocess communication. In this model, processes or objects can send and receive messages to other processes...
- memory segmentation and protection
- error handling
- I/OI/OI/O may refer to:* Input/output, a system of communication for information processing systems* Input-output model, an economic model of flow prediction between sectors...
directly by processes, and routing of interrupts back to processes
There is no provision for running any Supervisor/Privileged/kernel mode code on the 4000 systems—all operating system code runs as processes. Hence, device drivers, file system
File system
A file system is a means to organize data expected to be retained after a program terminates by providing procedures to store, retrieve and update data, as well as manage the available space on the device which contain it. A file system organizes data in an efficient manner and is tuned to the...
code, and other features which are often found within operating system kernels must be run in processes on the 4000 systems. Inherent in this is that they are all running in their own address spaces, protected from the actions of each other, just as all processes are.
Nucleus is configured by a set of system tables, and processes which have a need to modify the operation of nucleus are given access to the relevant system tables. This would be the case for processes which directly change the state of other processes, processes which allocate and delete memory segments, processes which can change the routing of messages between other processes or change the mapping of I/O devices to processes, etc. Normally system table access is limited to relatively few trusted processes, and other processes which need to perform operations such as loading processes, allocating memory, etc. will pass a message to the relevant trusted process which it will vet before performing the action and replying.
Instruction set
The 4000 series has a CISCComplex instruction set computer
A complex instruction set computer , is a computer where single instructions can execute several low-level operations and/or are capable of multi-step operations or addressing modes within single instructions...
instruction set
Instruction set
An instruction set, or instruction set architecture , is the part of the computer architecture related to programming, including the native data types, instructions, registers, addressing modes, memory architecture, interrupt and exception handling, and external I/O...
. It has 8-bit
8-bit
The first widely adopted 8-bit microprocessor was the Intel 8080, being used in many hobbyist computers of the late 1970s and early 1980s, often running the CP/M operating system. The Zilog Z80 and the Motorola 6800 were also used in similar computers...
bytes, big-endian
Endianness
In computing, the term endian or endianness refers to the ordering of individually addressable sub-components within the representation of a larger data item as stored in external memory . Each sub-component in the representation has a unique degree of significance, like the place value of digits...
, byte-addressable
Memory address
A digital computer's memory, more specifically main memory, consists of many memory locations, each having a memory address, a number, analogous to a street address, at which computer programs store and retrieve, machine code or data. Most application programs do not directly read and write to...
memory, two's complement
Two's complement
The two's complement of a binary number is defined as the value obtained by subtracting the number from a large power of two...
arithmetic, base-16 excess-64 floating point format
IBM Floating Point Architecture
IBM System/360 computers, and subsequent machines based on that architecture , support a hexadecimal floating-point format.In comparison to IEEE 754 floating-point, the IBM floating point format has a longer significand, and a shorter exponent....
(same as IBM System/360).
The model numbers less than 4090 are 16-bit processors, and model numbers from 4090 upwards are mixed 16-bit and 32-bit processors. This relates to pointer sizes available to programs. All systems support 16-bit pointers, which is known as CST (Current Segment Table) addressing. The 32-bit systems also support 32-bit pointers, known as PAS (Paged Address Space) addressing. Each process has a PAST (Program Accessible Segment Table) which lists which of the system's memory segments the program is permitted to access. CST addressing allows 4 of the PAST entries to be mapped at addresses 0KiB, 16KiB, 32KiB, and 48KiB, giving the 16-bit/64KiB address space. Programs which use more than 64KiB of memory must explicitly map the PAST entries they require at any moment into their 4 CST entries, although Nucleus will automatically map different code segments into the CSTs. PAS addressing allows programs to view their address space as a flat 32-bit address space, with successive PAST entries appearing every 16KiB, and Nucleus performing the PAST entry segment mapping automatically. The 32-bit systems support both CST and PAS addressing mixed in the same process. All instructions are 16 bits wide, except for some PAS addressing instructions which are 32-bits wide. Instructions can only be run from CST address space.
The 32-bit A register is the main accumulator register. There is a 32-bit B register too, which is most commonly used together with the A register as a 64-bit BA register for double precision floating point operations. A 16-bit X register is used mainly for array indexing, and two 16-bit Y and Z registers are used as 16-bit pointers. A 16-bit L register points to function local data, and a G register always contains zero which can be used as a 16-bit global pointer, and also an 8-bit, 16-bit, or 32-bit zero value. The 16-bit S (sequence) register points to the next instruction to be obeyed. The 8 bit EC register contains condition codes bits. (Some of this is illustrated in the much simpler instruction set of the GEC 2050
GEC 2050
The GEC 2050 was an 8-bit minicomputer produced during the 1970s, initially by Marconi Elliott Computer Systems of the UK, before the company renamed itself GEC Computers Limited...
.) A read-only keys register allows programs to read the value set on the front panel toggle switches (keys) by the operations staff. No 32-bit PAS pointer register exists—32-bit PAS pointers always reside in memory in the 16-bit CST address space, and are accessed by using a 16-bit pointer. There is no instruction set support for a stack
Stack (data structure)
In computer science, a stack is a last in, first out abstract data type and linear data structure. A stack can have any abstract data type as an element, but is characterized by only three fundamental operations: push, pop and stack top. The push operation adds a new item to the top of the stack,...
. There are a number of registers inaccessible to programs which are used by Nucleus, such as the hardware segment registers which point to the running process's 4 CSTs and master segment and PAS segments, and the system tables.
The instruction set contains instructions which operate register-register, store-register, register-store, and store-store. There are a set of string manipulation instructions which operate on variable lengths of store, copying, comparing, or scanning for a pattern. There are a number of Nucleus instructions which do things such as send message to another process or a peripheral device, receive a message or interrupt, change a CST entry to point to a different segment which is accessible to the process, etc.
The 4080 has a two stage instruction pipeline
Instruction pipeline
An instruction pipeline is a technique used in the design of computers and other digital electronic devices to increase their instruction throughput ....
. This becomes a four stage pipeline for the 4220, the highest performing system in the series. The entry level 415x and 4x6x systems have only a single stage pipeline.
The normal operating mode of the CPU is called Full Nucleus. All systems also support a limited mode of operation called Basic Test. In Basic Test mode, Nucleus is disabled, I/O is performed differently, and only a single program can run, restricted to the bottom 64KiB of store, but all other non-nucleus and non-PAS instructions operate normally. This mode is used very early during booting in order to setup the system tables required by Nucleus, before obeying a Switch Full Nucleus instruction. Once the system has switched to Full Nucleus, it cannot return to Basic Test mode without operator intervention at the front panel, in effect killing any operating system which was running. Basic Test mode is also used to run certain test software (hence the name).
Input/Output
The 4000 I/O design is based around having a number of Input/Output ProcessorsChannel I/O
In computer science, channel I/O is a generic term that refers to a high-performance input/output architecture that is implemented in various forms on a number of computer architectures, especially on mainframe computers...
known as IOPs, each of which interfaces between the store and a set of I/O controllers. The IOPs are controlled by the Nucleus function in the CPU, but once an I/O event is triggered, they operate autonomously without interaction with the CPU until the I/O completes. The Normal Interface IOPs can each support up to 255 or 256 simultaneous I/O operations, each on a separate Way. The I/O controllers on each IOP would each occupy one or more Ways, depending on how many simultaneous I/O operations they need to handle. The IOP polices each Way's access to main store, allowing only access to successive memory locations defined for the I/O operation that Way is currently performing. The earlier IOPs performed 8-bit and 16-bit wide store accesses, with a burst mode for doing up to 8 transfers together for higher throughput I/O controllers. The later IOPs added 32-bit wide store accesses.
All systems have at least 1 IOP. On the 4080, this first IOP was called the Basic Multiplexer Channel, or BMC, and the 4080 front panel provides for controlling both the CPU and the BMC. The entry level 415x and 4x6x systems have their first IOP (Integral Multiplexer Channel, or IMC) integrated into the Nucleus firmware, and thus I/O operations on the IMC did have some impact on CPU performance, although the 4x6x systems could have additional external IOPs added too. The 4000 series Nucleus i/o instructions and system tables allow for up to 8 IOPs, although most of the models in the 4000 series range had some type of hardware limitation which reduced this. The 408x systems had 4-ported store, with the CPU and first IOP sharing one of these, and up to 3 additional IOPs connected to the remaining store ports. (Early documentation shows these additional store ports were also designed to connect additional CPUs, although this was not a configuration which was ever sold using 4080 processors.) Later models had more varied number of store ports, depending on how many store port boards could be fitted into the system. The 4190 could support the full complement of 8 IOPs, and the 4190D supported 8 IOPs with 2 CPUs.
Some commonly used I/O Controllers are the interval timer
Programmable Interval Timer
In computing and in embedded systems, a programmable interval timer is a counter which triggers an interrupt when it reaches the programmed count.- Common features :...
, system console
System console
The system console, root console or simply console is the text entry and display device for system administration messages, particularly those from the BIOS or boot loader, the kernel, from the init system and from the system logger...
controller, punched tape
Punched tape
Punched tape or paper tape is an obsolete form of data storage, consisting of a long strip of paper in which holes are punched to store data...
reader and punch controllers, line printer
Line printer
The line printer is a form of high speed impact printer in which one line of type is printed at a time. They are mostly associated with the early days of computing, but the technology is still in use...
controller (all these use just a single Way), a number of SMD
Storage Module Device
Storage Module Device was a family of storage devices first shipped by Control Data Corporation in December 1973 as the CDC 9760 40 MB storage module disk drive. The CDC 9762 80 MB variant was announced in June 1974 and the CDC 9764 150 MB and the CDC 9766 300 MB variants were announced in 1975...
(and earlier disk bus interface) disk controllers for controlling up to four drives (all using 2 Ways), Pertec PPC magnetic tape
Magnetic tape
Magnetic tape is a medium for magnetic recording, made of a thin magnetizable coating on a long, narrow strip of plastic. It was developed in Germany, based on magnetic wire recording. Devices that record and play back audio and video using magnetic tape are tape recorders and video tape recorders...
controllers for up to four ½" tape drives, and a number of multi ported synchronous
Synchronous circuit
A synchronous circuit is a digital circuit in which the parts are synchronized by a clock signal.In an ideal synchronous circuit, every change in the logical levels of its storage components is simultaneous. These transitions follow the level change of a special signal called the clock...
and asynchronous
Asynchronous circuit
An asynchronous circuit is a circuit in which the parts are largely autonomous. They are not governed by a clock circuit or global clock signal, but instead need only wait for the signals that indicate completion of instructions and operations. These signals are specified by simple data transfer...
serial communication
Serial communication
In telecommunication and computer science, serial communication is the process of sending data one bit at a time, sequentially, over a communication channel or computer bus. This is in contrast to parallel communication, where several bits are sent as a whole, on a link with several parallel channels...
controllers (using between 4 and 32 Ways). A digital I/O board (using 4 Ways) was commonly used for direct process control interfacing, and for providing a fast parallel link between systems. A CAMAC crate controller was also available (again, used for process control interfacing). The Normal Interface bus which these controllers plug into is a published interface, and many customers also built their own controllers for their own specific process control requirements. Also, the earlier GEC 2050 minicomputer used an 8-bit version of the Normal Interface, and most I/O Controllers could be used on both ranges of systems.
All the IOPs designed and built through the 1970s provided the same Normal Interface bus for I/O Controllers, and the I/O controllers could generally be used in any of them. In the 1980s, some more specialised IOPs were designed. A Direct Memory Access Director (DMAD) IOP allowed for a new type of I/O controller which had more freedom to access main memory, and allowed the design of more intelligent communications controllers. A SCSI
SCSI
Small Computer System Interface is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces. SCSI is most commonly used for hard disks and tape drives, but it...
IOP generated a SCSI bus for attaching more modern disks, and also included an integrated Interval Timer, system console controller, and Calendar Clock so that an additional Normal Interface IOP and separate controllers was not required to support just these functions.
Customers
Users of GEC 4000 series systems included many British university physics and engineering departments, the central computing service of University College LondonUniversity College London
University College London is a public research university located in London, United Kingdom and the oldest and largest constituent college of the federal University of London...
(Euclid) and Keele University
Keele University
Keele University is a campus university near Newcastle-under-Lyme in Staffordshire, England. Founded in 1949 as an experimental college dedicated to a broad curriculum and interdisciplinary study, Keele is most notable for pioneering the dual honours degree in Britain...
, the JANET
JANET
JANET is a private British government-funded computer network dedicated to education and research. All further- and higher-education organisations in the UK are connected to JANET, as are all the Research Councils; the majority of these sites are connected via 20 metropolitan area networks JANET...
academic/research network X.25
X.25
X.25 is an ITU-T standard protocol suite for packet switched wide area network communication. An X.25 WAN consists of packet-switching exchange nodes as the networking hardware, and leased lines, Plain old telephone service connections or ISDN connections as physical links...
switching backbone, Rutherford-Appleton Laboratory, Daresbury Laboratory
Daresbury Laboratory
Daresbury Laboratory is a scientific research laboratory near Daresbury in Cheshire, England, which began operations in 1962 and was officially opened on 16 June 1967 as the Daresbury Nuclear Physics Laboratory by the then Prime Minister of United Kingdom, Harold Wilson...
, Harwell Laboratory, NERC
Natural Environment Research Council
The Natural Environment Research Council is a British research council that supports research, training and knowledge transfer activities in the environmental sciences.-History:...
, Met Office
Met Office
The Met Office , is the United Kingdom's national weather service, and a trading fund of the Department for Business, Innovation and Skills...
, CERN
CERN
The European Organization for Nuclear Research , known as CERN , is an international organization whose purpose is to operate the world's largest particle physics laboratory, which is situated in the northwest suburbs of Geneva on the Franco–Swiss border...
, ICI
Imperial Chemical Industries
Imperial Chemical Industries was a British chemical company, taken over by AkzoNobel, a Dutch conglomerate, one of the largest chemical producers in the world. In its heyday, ICI was the largest manufacturing company in the British Empire, and commonly regarded as a "bellwether of the British...
, British Telecom, SIP
Telecom Italia
Telecom Italia is the largest Italian telecommunications company, also active in the media and manufacturing industries. Now a private concern listed on the Borsa Italiana, it was founded in 1994 by the merger of several state-owned telecommunications companies, the most important of which was...
(Italian telco
Telephone company
A telephone company is a service provider of telecommunications services such as telephony and data communications access. Many were at one time nationalized or state-regulated monopolies...
), Plessey
Plessey
The Plessey Company plc was a British-based international electronics, defence and telecommunications company. It originated in 1917, growing and diversifying into electronics. It expanded after the second world war by acquisition of companies and formed overseas companies...
, British Steel
British Steel
British Steel was a major British steel producer. It originated as a nationalised industry, the British Steel Corporation , formed in 1967. This was converted to a public limited company, British Steel PLC, and privatised in 1988. It was once a constituent of the FTSE 100 Index...
and BHP Steel real-time control of rolling steel mills, British Rail
British Rail
British Railways , which from 1965 traded as British Rail, was the operator of most of the rail transport in Great Britain between 1948 and 1997. It was formed from the nationalisation of the "Big Four" British railway companies and lasted until the gradual privatisation of British Rail, in stages...
and London Underground
London Underground
The London Underground is a rapid transit system serving a large part of Greater London and some parts of Buckinghamshire, Hertfordshire and Essex in England...
for real-time train scheduling, London Fire Brigade
London Fire Brigade
The London Fire Brigade is the statutory fire and rescue service for London.Founded in 1865, it is the largest of the fire services in the United Kingdom and the fourth-largest in the world with nearly 7,000 staff, including 5,800 operational firefighters based in 112 fire...
and Durham Fire Brigade command and control systems, Suffolk Constabulary
Suffolk Constabulary
Suffolk Constabulary is the territorial police force responsible for policing Suffolk in East Anglia, England.Suffolk Constabulary is responsible for policing an area of , with a population of...
, and most of the National Videotex
Videotex
Videotex was one of the earliest implementations of an "end-user information system". From the late 1970s to mid-1980s, it was used to deliver information to a user in computer-like format, typically to be displayed on a television.In a strict definition, videotex refers to systems that provide...
systems in the world including the Prestel
Prestel
Prestel , the brand name for the UK Post Office's Viewdata technology, was an interactive videotex system developed during the late 1970s and commercially launched in 1979...
viewdata
Viewdata
Viewdata is a Videotex implementation. It is a type of information retrieval service in which a subscriber can access a remote database via a common carrier channel, request data and receive requested data on a video display over a separate channel. Samuel Fedida was credited as inventor of the...
service.
At the Rutherford-Appleton Laboratory a GEC 4000 system was used to control the synchrotron and injectors used for the ISIS
ISIS
ISIS is an industry standard interface for image scanning technologies, developed by Pixel Translations in 1990 ....
neutron
Neutron
The neutron is a subatomic hadron particle which has the symbol or , no net electric charge and a mass slightly larger than that of a proton. With the exception of hydrogen, nuclei of atoms consist of protons and neutrons, which are therefore collectively referred to as nucleons. The number of...
spallation source until 1998.
A GEC 4080M was also used as the central processor for the radar system of the ill-fated Nimrod AEW.3
British Aerospace Nimrod AEW3
The British Aerospace Nimrod AEW3 was a planned airborne early warning aircraft intended as to provide airborne radar cover for the air defence of the United Kingdom by the Royal Air Force...
airborne early warning
Airborne Early Warning
An airborne early warning and control system is an airborne radar system designed to detect aircraft at long ranges and control and command the battle space in an air engagement by directing fighter and attack plane strikes...
aircraft.
Models
A number of variants of the GEC 4000 processor were produced, including (in approximate chronological order):- 4080: original 1973 model with 64–256 KiB of core memory
- 4082: 4080 with up to 1 MiB of memory
- 4070: entry-level model without memory interleaving
- 4085: 4082 with semiconductorSemiconductorA semiconductor is a material with electrical conductivity due to electron flow intermediate in magnitude between that of a conductor and an insulator. This means a conductivity roughly in the range of 103 to 10−8 siemens per centimeter...
memory - 4060: entry-level model based on AMDAdvanced Micro DevicesAdvanced Micro Devices, Inc. or AMD is an American multinational semiconductor company based in Sunnyvale, California, that develops computer processors and related technologies for commercial and consumer markets...
Am2900 bit-slice processors - 4062/4065: 4060 supporting up to 1 MiB memory
- 4080M: compact ruggedised 4080 for military applications
- 4090: Am2900-based with 32-bit addressing extensions and up to 4 MiB of memory
- 4190: revised 4090 with up to 16 MiB memory
- 4180: cheaper, slower version of the 4190 (no memory cache, no fast multiply unit)
- 4060M: compact ruggedized 4060 for military applications
- 4160: 4065 with the 4090 32-bit addressing extensions
- 4150: desktop 4160
- 4162: 4160 with DMAD IOP(s) for high speed communications controllers
- 4195: compact 4190
- 4185: cheaper, slower version of the 4195 (no memory cache, no fast multiply unit)
- 4151: rackmount 4150
- 4190D: dual-processor 4190
- 4193: 4195 with SCSISCSISmall Computer System Interface is a set of standards for physically connecting and transferring data between computers and peripheral devices. The SCSI standards define commands, protocols, and electrical and optical interfaces. SCSI is most commonly used for hard disks and tape drives, but it...
IOP replacing the default Normal Interface IOP - 4220: Reimplement 4190 using gate arrayGate arrayA gate array or uncommitted logic array is an approach to the design and manufacture of application-specific integrated circuits...
processor technology - 4310: Motorola 8810088000The 88000 is a RISC instruction set architecture developed by Motorola. The 88000 was Motorola's attempt at a home-grown RISC architecture, started in the 1980s. The 88000 arrived on the market some two years after the competing SPARC and MIPS...
MVME187Motorola Single Board ComputersMotorola Single Board Computers is Motorola's production line of computer boards for embedded systems. There were three different lines : mvme68k, mvmeppc and mvme88k. The first version of the board appeared in 1988...
-based system emulating a GEC 4220
Software
Several operating systems were available for the GEC 4000 series, including the following:- COS: Core Operating System, for diskless real-time systems
- DOS: Disk Operating System, for real-time systems, providing a filesystem and swapping facilities
- OS4000OS4000OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers...
: a multi-userMulti-userMulti-user is a term that defines an operating system or application software that allows concurrent access by multiple users of a computer. Time-sharing systems are multi-user systems. Most batch processing systems for mainframe computers may also be considered "multi-user", to avoid leaving the...
system supporting batch and interactive use, and transaction processing - SCP-2: Secure Operating System (DOD A1/B3Trusted Computer System Evaluation CriteriaTrusted Computer System Evaluation Criteria is a United States Government Department of Defense standard that sets basic requirements for assessing the effectiveness of computer security controls built into a computer system...
) Multilevel securityMultilevel securityMultilevel security or Multiple Levels of Security is the application of a computer system to process information with different sensitivities , permit simultaneous access by users with different security clearances and needs-to-know, and prevent users from obtaining access to information for...
Programming languages available included Babbage
Babbage (programming language)
Babbage is the high level assembly language for the GEC 4000 series minicomputers. It was named after Charles Babbage, an English computing pioneer.- Example :PROCESS CHAPTER FACTORIALENTRY LABEL ENTRYPOINT...
(a high-level assembly language), FORTRAN IV, CORAL 66, ALGOL
ALGOL
ALGOL is a family of imperative computer programming languages originally developed in the mid 1950s which greatly influenced many other languages and became the de facto way algorithms were described in textbooks and academic works for almost the next 30 years...
, APL (programming language) and BASIC
BASIC
BASIC is a family of general-purpose, high-level programming languages whose design philosophy emphasizes ease of use - the name is an acronym from Beginner's All-purpose Symbolic Instruction Code....
.
See also
- GEC ComputersGEC ComputersGEC Computers Limited was the computer manufacturing company under the GEC holding company.-History:Starting life as Elliott Automation, the data processing computer products were transferred to ICT/ICL and non-computing products to English Electric as part of a reorganisation of the parent company...
- OS4000OS4000OS4000 is a proprietary operating system introduced by GEC Computers Limited in 1977 as the successor to GEC DOS, for its range of GEC 4000 series 16-bit, and later 32-bit, minicomputers...
- GEC Series 63GEC Series 63The GEC Series 63 was a 32-bit minicomputer produced by GEC Computers Limited of the UK during the 1980s in conjunction with A.B. Dick in USA. During development, the computer was known as the R Project. The hardware development was done in Scottsdale, Arizona whilst the software was the...
- GEC 2050GEC 2050The GEC 2050 was an 8-bit minicomputer produced during the 1970s, initially by Marconi Elliott Computer Systems of the UK, before the company renamed itself GEC Computers Limited...
8-bit minicomputer