Reviewer: Harry Fairhead
Magazine: Electronics & Computing Monthly
Date: December 1982
Before I launch into what I fully intend to be an objective appraisal of the BBC Micro I feel I had better come clean and admit that as far as I am concerned the BBC Micro (Model B) takes first prize in almost any competition. It is decidely my favourite micro - but before you dismess the rest of this article as biased and partisan let me assure you that I have had had, and taken, every opportunity to try out the opposition.
In most cases reviewers are sent a micro on loan for four weeks (though I have known cases when the period was four days!) and they have to find out all about it just as quickly as they can. I've had my BBC Model B for nine months and have been able to take my time to discover its good points (and to learn to live with its bad ones!) In fact the BBC Micro I've used for most of this period was one of the very first to be sent out and was recently swopped by Acorn for one with the latest MOS, complete with a disc controller card. I'd grown attatched to the old model for one thing, its non-switched mode power supply meant it had a super hot spot that kept me warm all last winter - but, more importantly, it had been entirely reliable and had done me good service. However, with the lastest MOS I've got access to all the BBC Micro's many sophisticated features so I'm not complaining!
The BBC Micro has a very smart appearance. Its cream coloured plastic case is reasonably sturdy and its keyboard has a neat layout. Above the standard QWERTY keyboard there are nine red programmable "function" keys, which you can "define" to generate any character or string that you want, for example, it's very useful to set them to commands such as LIST or *TAPE. There are four cursor control keys at the top right of the keyboard and these and the COPY key are a lighter brown colour than the rest of the keys. The copy facility is a feature that I really appreciated when I first discovered how useful it is - both when writing or altering programs or when text processing. Now I find that I rely on it so much that I'm lost without it. I have only one criticism of the keyboard and my grouse is the spacebar. Those on both of the models I've used have only responded if you hit them near the middle and, if you are a left-handed, one-fingered typist like me, you can type whole lines without ever throwing a space! (But using the COPY key it's simple to correct such mistakes!)
Inside the Case
It's quite easy to lift the lid off the BBC Micro - you simply remove four screws. The layout inside is neat There is just one PCB and all the chips are neatly socketed. The 2 MHz 6502 is in the centre of the board. If you are aware of the early history of the BBC Micro project you may know that the 6502 was specifically ruled out in the early specifications for the machine, which stipulated a Z80 CPU. However, it obviously made sense for Acorn, who had already used the 6502 in their ATOM and had invested time and effort in developing a BASIC interpreter using it, to stick with the 6502. This decision certainly paid off and the result - BBC BASIC - is a one of the BBC Micro's winning points.
The great thing about BBC BASIC is that it has all the advantages of BASIC - straightforwardness PLUS the advantages of a structured language such as PASCAL. Using its "procedures and functions" you can build up large programs from smaller routines. Once you've got used to this method or programming you find that it makes life much easier - especially when it comes to debugging, making modifications or adding extra routines.
BBC BASIC is fast - to my knowledge it is the fastest BASIC running on a popular micro - and its easy to mix assembler and BASIC, which means you can speed up critical parts of your programs even further.
One of the most versatile features of the BBC Micro is its graphics displays. The Model B machine can operate in any of the eight modes listed below. Notice that only three of these are available on the Model A machine. This is because the memory used by each mode is taken from user RAM. So using a Model A machine in Modes 4 or 5 does not leave much memory available for programs. This is a fairly serious drawback as Mode 7, which can theoretically use 16 colours, in fact offers only limited use of colour and involves a good deal of fiddling programming.
|4||320x256||2||40x32||10K||A & B|
|5||160x256||4||20x32||10K||A & B|
|6||2||40x25||8K||A & B|
|7||Teletext||16||40x25||1K||A & B|
The 16 colours are actually eight solid colours (black, red, green, yellow, blue, magenta, cyan and white) and eight flashing combinations. Unlike some other micros the colours are clear and true and you can display them wherever you want on the screen.
Another noteworthy facility of the BBC Micro is its sound, there are three tone channels and they can be used simultaneously to produce three note chords and so on. As well as the SOUND command, which can be used to produce "pure" tones, there is the ENVELOPE command which can be used to modulate the quality of the sound. This command is a tricky one to master but if you persevere you can use it to produce some impressive effects.
A fully expandable system
If I've not yet managed to convince you that the BBC Micro is the best invention since the wheel, this next section should provide the conclusive evidence. The BBC Micro (Model B) is not just another all-singing, all-dancing home computer, it is the basis of a really powerful system and one that will last into an exciting future.
Your new BBC Micro is actually more difficult to get started with than many of its rivals. It comes with a lead that connects it to a television but without a cassette lead. The BBC Micro has a standard 7-pin DIN audio socket and the User Guide advises you to obtain a lead with "suitable plugs for your particular recorder" at one end and either a 7-pin DIN or a 5-pin DIN at the other. In fact it is preferable to use a 7-pin DIN as you won't be able to take advantage of computer control of the cassette motor if you use a 5-pin DIN. A cassette recorder marketed by BBC Microcomputer Systems is now available and this comes complete with a lead. Whatever cassette recorder is used, the system, once set up, is easy to use and reliable. There are two recording speeds, 30 and 120 characters per second and the only possible problem is trying to load tapes at the wrong speed. (If you save at 30 cps then you must load it at 30 cps!)
Alternatively, you can use disc storage with your Model B BBC Micro. The disc controller is an optional extra and enables the use of standard disc drives. Again, special customised disc drives (single or dual) are available.
Its graphics and sound capabilities make the BBC Micro good at fun and games and specially designed games paddles are now available to make it even better. These have a chunky, space-age appearance with finger grips and a trigger button on the shaft and a steering stick on the top. Of course, they can be put to more serious uses in the laboratory.
Another option that will be fun as well as having practical applications is the speech synthesiser. Having actually heard a prototype of this I can report that the BBC Micro's voice is clear and "British" sounding and so lives up to its name.
The Model B (only) has an RS423 serial interface (which is an advanced RS232 but uses a 5-pin DIN socket instead of the familiar 25-pin D connector) an eight-bit Centronics interface (with a 26-pin ribbon cable plug) and an eight-bit user port (which is used via a 20-pin ribbon cable plug).
The printer port, the user port and the disc drive port are to be found on the underside of the Model B's case. Next to them are two other interfaces. The first is a 34-pin ribbon plug labelled "1 MHz Bus". This is provided for connection to, among other things, Teletext and Prestel. The BBC Micro is therefore ready for the "telesoftware" developments of the future. What this means is that it will be possible to "capture" information of all sorts, including programs as well as text, direct from the television. The second machine interface is labelled the "Tube". This has been provided so that the BBC Micro can be equipped with a second processor. Those that are likely to be available soon are a second 6502 with 64K of RAM and a Z80, also with 64K, which will allow the BBC Micro to use CP/M version 2.2. These extra processors will obviously increase its range of software options.
Both Model As and Model Bs can be fitted with an Econet interface. This means that you can connect a large number of them together to form a "local network". This enables a number of micros to communicate with each other and to share important and expensive peripherals - such as disc drives or printers. This has great potential for applications in educational settings, for example.
Your new BBC Micro comes with its "Welcome" pack - a cassette tape that and accompanying booklet that show off many of the features of the machine, both the mundane ones like the keyboard and exotic ones like the graphics. It includes something for everyone and I certainly enjoued using it when my BBC Micro first arrived. It was only a couple of months ago that the final version of the "User Guide" actually arrived and it had been eagerly awaited by literally thousands of BBC Micro users - would it given them the answers to all the problems they had encountered? The answer is, however, "not entirely". This is not meant as a criticism of the "User Guide" which is a weighty tome of over 500 pages and is full of clearly presented useful information, but is rather a re-flectio of the complexity of the BBC Micro which has seemingly endless potential for invention and discovery. This is what makes it an enthusiasts dream and the "User Guide" is sufficiently comprehensive for it not to become a beginner's nightmare.
When comtemplating buying a micro, for whatever purpose, it is always important to consider what software is available for it. In the case of the BBC Micro the prospects are very good. Many independent software publishers quickly got to work and programs of all varieties, from games to word processors, started to appear within weeks of the first machines being delivered. Acorn's in-house software, Acornsoft, now has an impressive list of cassette titles including games, educational packages and two alternative languages LISP and FORTH. Some of these will, of course, only run on the Model B. As yet software is mainly on cassette but both the A and B models can be fitted to take plug in ROM cartridges and these and, of course, the advent of discs will widen the options.
In such a short article it is impossible to do more than sketch out the basic features of the BBC Micro. However, I hope I've been able to indicate my own enthusiasm for the machine. My advice to anybody considering buying a BBC Micro would be to go for the Model B - its extra facilities are certainly worth the extra money. In fact my advice to anybody considering the Model B is unequivocal - it is "Go ahead, you'll find it will still be going when its current competitors have faded into the mists of time".