Grundy NewBrain
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The Grundy NewBrain was a microcomputer sold in the early-1980s by Grundy Business Systems Ltd of Teddington and Cambridge, England.
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[edit] Beginnings
The NewBrain project was started in 1978 when Sinclair Radionics began design work with Mike Wakefield as the designer and Basil Smith as the software engineer. This project was intended to provide competition for Apple and hardly fitted in with Sinclair's focus on inexpensive consumer-oriented products. When it became obvious to Sinclair that the NewBrain could not be made for the sub-£100 price he envisaged his thoughts turned to the ZX80 that was to be developed by his other company, Science of Cambridge Ltd.
The NewBrain project was moved to Newbury Laboratories by the National Enterprise Board (NEB), the owner of both Sinclair Radionics and Newbury Labs.
[edit] NewBrain and the BBC micro project
In early 1980, the BBC Further Education department conceived the idea of a computer literacy programme, mostly as a follow-up to a BBC documentary, The Mighty Micro, in which Dr Christopher Evans from the UK National Physical Laboratory predicted the coming (micro)computer revolution. It was a very influential documentary — so much so that questions were asked in parliament. BBC Engineering was instructed to attempt to draw up an objective specification.
As a result of the questions in Parliament, the Department of Industry (DoI) became interested in the programme, as did BBC Enterprises, which saw an opportunity to sell a machine to go with the series.
Eventually, under some pressure from the DoI to choose a British system, the BBC 'chose' the NewBrain. The BBC specification was closely written around the NewBrain specification, with (presumably) the expectation that Newbury Laboratories would tender and win. It was not to be. Although the NewBrain was under heavy development by Newbury, it soon became clear that Newbury was not going to be able to produce it. Newbury did not tender (resulting in Clive Sinclair allegedly making the comment 'More no-brain than NewBrain') and opening the door for other companies. The BBC's programmes, initially scheduled for Autumn 1981, were moved back to Spring 1982. After Chris Curry and Clive Sinclair found out about the BBC's plans, the BBC allowed other manufacturers to submit their proposals. Chris Curry visited the BBC and persuaded them to change the specification so that Acorn could submit their design.
The BBC eventually chose a computer from Acorn Computers Ltd.
As a result of the BBC's decision, the British Technology Group, which had replaced the NEB, sold the final design and production to Grundy. Grundy had been looking for an entrant into the personal computer business, as they were already producing a 'dumb terminal.'
[edit] Available models
Two models were released. The 'A' model had display to either a TV or a monitor. The 'AD' included a one-line, 16-character, vacuum fluorescent (VF) display on the unit. Because programmers could not tell if the 'A' or 'AD' model was being used the VF display was mostly a curiosity, although it did permit operation without a TV screen or monitor - the VF display responded to the cursor keys and scrolled around the screen display area. One additional model was released, but this was a custom version for a pharmaceutical chain, with no screen display - only the VF display - and was never generally discussed.
An expansion chassis was released, providing additional memory - nominally up to 2 MB - but the hardware was unreliable, especially the various connectors to other devices.
CP/M 2.2 was also available, although this was released late, and close to the demise of Grundy Business Systems.
[edit] Commercial exploitation
Grundy failed to manage adequately the design or production of the NewBrain. The colour scheme (cream and brown) was chosen by default as being the colours available by the case manufacturer - the proposed colour scheme (orange and ?brown?) was never formally agreed[1]. Pricing was high for a monochrome computer (around £250 in 1983) when a colour computer (the ZX Spectrum) could be had for half that price. The computer was made up of extensive discrete logic components, when competitors were using logic arrays that greatly reduced the component count, so that the NewBrain was expensive to produce and assemble.
Advertising was poor, and available software was worse. Too much was in the form of crude BASIC programs, when competing machines were offering commercial software in machine code - thus, their offerings were smaller and faster. An 'optimisation' of the NewBrain was that BASIC was stored twice - once as a token scheme, and a second time as 'p-code', effectively a stack-based Forth-type scheme intended to allow the interpreter to call ROM routines more rapidly. However, this had the effect of slowing down large programs, as the p-code was generated, executed then discarded, and also reduced the data capacity because of the space allocated for the p-code. For its time the NewBrain was fast, allegedly because of the p-code approach, but at the time all personal computers were offering interpreted variants of BASIC. NewBrain marketing claimed that this was 'compiled' code, which produced little more than derision from the PC World review.
[edit] Aspects of the software
The software was unusual. All I/O was stream-based, and orthogonal: any device could be replaced by an alternative, although the manual did warn that devices had to be chosen with care. Screen output could be sent to the keyboard device, although there would be no output, and input could be requested from the printer, although again little would happen. This approach did make it easy to write programs that could swap between input & output coming from a screen/keyboard or a tape. The maths package was also unusual, having approximately 8 figures of accuracy and a dynamic range of approximately 10-150 to 10150, compared to most common machines having 6 figure accuracy and a dynamic range of 10-38 to 10+38. This was achieved by using base 256 for the floating point format, rather than the more common base 2, and using 10 bytes for storing numbers, rather than the more common four. Nine bytes stored the basic number, with the last byte storing the sign in the first bit, and the remaining seven bits storing the exponent. This approach, however, meant that the worst-case could lead to 7 of the top 8 bits storing effectively no information, losing 2-3 decimal figures of accuracy, unlike the base 2 methods.
The graphics screen was separate to the text screen, and was opened as a new output stream that shared space with the text screen. The graphics commands were based on 'turtle' keywords and provided a flexible means of drawing. The last two generations of NewBrain ROMs included new graphics commands - ROM 1.9 had two more commands, and ROM 2.0 (never released in the UK) some more. But to ensure compatibility little software would use these additional commands. There were signs that Grundy had been planning to offer the ROM 2.0 ROMs to existing users, but the company folded around this time.
The BASIC was described as an extended version of ANSI BASIC, but it was an extended version of ANSI minimal BASIC, and was thus better regarded as an extended version of a cut-back version. The most apparent limit was the restriction of variable names to either a letter, or a letter followed by a digit, when the 'standard' Microsoft BASIC supported a letter followed by an alphanumeric, and BBC BASIC allowed names of up to 32 characters. There were no procedures, only the classical GOTO and GOSUB.
Grundy offered a 'Software Technical Manual' which was little more than the documentation of an undelivered assembler. This manual allowed users to know of various routines that could be called in the ROM, but did not describe either the memory locations or calling parameters. That omission was eventually filled by one of the user groups, but by that time Grundy Computers had folded and the NewBrain had been sold on to Tradecom.
Grundy delivered late on expansions that may have helped keep the NewBrain competitive - the floppy disk controller was late, the expansion pack (with additional memory) was late, flaky and parts of the hardware did not work; proposed software offerings (Pascal, Comal, a flight simulator) were never delivered; talk was made of a colour model that never materialised. The proposed battery pack, producing a 'portable' computer, was never delivered - there was a pack, but it had a battery life of around 30 minutes, which Grundy recognised as impractical for release. Development of this portable model was discontinued. When the NewBrain was first announced, in 1981 by Newbury, much had been made of the availability of a portable model.
[edit] The end
Tradecom purchased Grundy Business Systems in 1983 in order to fulfill a contract to supply microcomputers to schools and training centres in Holland. Although Tradecom claimed that they would push the NewBrain, continue its development, and ensure that it would have a future, in practice they did little of this. The NewBrain faded rapidly, with no new machines built. Tradecom's NewBrains were supplied entirely by existing stock. A press release was made of a new factory in India to provide NewBrains to the Indian market and supply Europe, but nothing materialised.
[edit] What remains
The Dutch NewBrain user group has PDF downloads of various publications, and a link to a Greek website that contains a PC-based emulator. The Dutch website has most of the programs that were available for the NewBrain, and these can be run on the emulator.
[edit] Specifications
| Pricing: | 229.00 GBP (United Kingdom, 1980), 48,000.00 GRD (Greece, 1985) |
|---|---|
| Emphasis: | Education, Portable computing, Programming, Small business |
| Timeline: | Released: 1983 |
| CPU type: | Z80 |
| CPU word length: | 8 bits |
| CPU clock rate: | 4 MHz |
| ROM Size: | 28 KB |
| RAM Size: | 16 KB, 32 KB |
| Maximum RAM Size: | 2 MB |
| Number of keys: | 62 |
| Keyboard and one-line VF display chip: | COP400 MCU |
| Graphics modes: | 256x256, 320x256, 512x256, 640x256x2 |
| Text modes: | 32x25, 32x30, 40x25, 40x30, 64x25, 64x30, 80x25x2, 80x30x2 |
| Total number of colours: | 2 |
| I/O Ports: | 2x Tape recorder, Composite video, Expansion, RS-232, TV output, User port |
[edit] References
- ^ Newbrain User Group Issue #1
