John Lettice finds the SPDOS disk interface an attractive option

A long time ago, in a magazine far, far away (issue 57, to be precise), PCN got a chance to preview a prototype disk interface for the Spectrum. Its developers, Dimitri Koveos and Dave Farnborough, who were at that time with Morex, were looking for the necessary funding to get what we felt was an excellent system into production.

Then it all went quiet, and when the Timex drives for the Spectrum came out at the end of last year it looked like Dimitri and Dave had missed the boat.

But after trials and tribulations the interface has now made it to the marketplace, masterminded by Dave and Dimitri in their new incarnation as Abbeydale Designers and marketed by Watford Electronics. Watford has built up a reputation as a BBC specialist, but in order to fit the SPDOS interface to Watford's BBC disk drives, all you need to do is change the plug.

This means that you can use practically any 3", 3.5" or 5.25" drive with the system, and depending on which one you choose you can have up to 800K storage on each of four drives.

It also shouldn't be too difficult to connect up any existing drives you may have, provided they have a standard Shugart 34-way interface, as the relevant cables are standard Tandy.

The manual supplied is brief, but clear and to the point - SPDOS itself seems considerably easier to use than Masterfile, Omnicalc 2 and Tasword, which come bundled with the system and have their own manuals bound in with the SPDOS manual. But do I spot a desperate attempt to get Sir Clive to adopt SPDOS as the official system?

"Sir Clive Sinclair's aspirations and Da Vincian insight into the technological future have contributed a great deal into forming the shape of computing as we know it," grovels the introduction. Insight I can cope with, but 'Da Vincian'?

For all that, it is a useful piece of work for those - the majority of Spectrum owners - who have no experience of disk systems. It explains what a disk system is in relatively plain English, the setting up instructions are clear and my only minor complaint is that Abbeydale could have made doubly sure the connector was plugged in the right way round by marking one side of it.

The interface itself consists of a black box, flattish in cross-section, with a through edge connector, a reset button and a power-on light. It also has one of these handy little holes so that you have to put the power cable through it to plug it into the Spectrum.

The system boots up automatically when the machine is switched on, taking just over two seconds. This produces an SPDOS copyright message on the screen, and if you get into trouble the system is easily re-booted.

As far as fast storage systems for the Spectrum go, the fashion seems to be to use an amended form of the existing Spectrum command system rather than generate a whole new DOS command mode. SPDOS conforms to this trend, rightly in my opinion, and uses the Spectrum and Microdrive commands practically intact, the only difference being that they should be preceded by PRINT#4. So with a single drive system, you load with the command PRINT#4:LOAD "filename".

If you have more than one drive, it's just a matter of specifying the drive with an additional PRINT statement on the end of the command. MOVE is one of the most useful commands, governing renaming and copying of files.

This can be done singly or it can systematically copy all files from one drive to another. Other notable features are a wildcard facility on ERASE, allowing you to wipe all files within a specific category, and the ability to list sub-directories by incorporating varying strings in filenames.

Abbeydale needs to generate software support for SPDOS, and is therefore building in a fair bit of anti-piracy work in the drives. The MERGE command, for example, has been enhanced so that an attempt to MERGE a program saved to auto-run results in just that - the program auto-runs.

The system disk backup program, COPYSYS, is a particularly good - and, dare I say it, over the top - example of the system's built-in protection. This gives you a menu to follow ehn you go through during the backup, and woe betide anyone who tries any funny business, as it resets the machine.

I'm particularly glad to see this disk system up and running at last. It's fast, easy to use and with the bundled software should be particularly attractive to the surprisingly large Spectrum business user community. In the business field, OCP is currently marketing its Stock Manager program in SPDOS format, and intends to convert more of its output in the near future.

Currently its main rival would seem to be the Timex system, and as a disk system SPDOS is certainly superior, although if the Timex gets better support, this could cancel out any advantage SPDOS has. Viewed in this light, perhaps 'Da Vincian' is the right expression...

Features 4/5
Documentation 4/5
Performance 4/5
Overall value 4/5