At the time of the Amstrad deal Sinclair was well advanced with development plans for a new Spectrum micro - the SuperSpectrum - and Sinclair User has now uncovered the full details.
Designed to replace the Spectrum 128 at under £200, the SuperSpectrum - codenamed 'Loki' after the Norse 'gamesplayer' God - is an entertainment software computer with graphics and sound the likes of which have never been seen even at five times the price.
Inspiration for the SuperSpectrum undoubtedly comes from Commodore's incredible Amiga machine. The key to the startling power of the SuperSpectrum - as with the Amiga - lies in its special custom chips. The SuperSpectrum has two sophisticated chips handling the video screen (Rasterop device) and sound synthesis, both with direct memory access. This gives the machine the potential to produce incredibly fast 3D graphics manipulations and sound of hi-fi quality.
But where the Amiga costs over £1500, the SuperSpectrum will scrape in under £200.
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The trick is that the SuperSpectrum is still an 8-bit machine. In fact, it even has a Spectrum 48K compatible mode if you want it. The processor it uses is a special up-rated version of the old Spectrum's Z80A. Called the Z80H, the new chip runs twice as fast, at an incredible 7 MHz. At this speed there is time to provide a fast interrupt handler that keeps pace with the video display, still leaving time to run programs faster than the Spectrum 48.
But the real power of the micro comes from the two custom chips. Because they have direct access to the memory, during time which would otherwise be wasted, large amounts of screen data can be moved about at speeds that the CPU couldn't manage, even if it had nothing else to do.
To match the CPU, fast-access Ram is required, and the SuperSpectrum will be equipped with two 64K banks each made up of two 256K-bit chips. One bank will be connected to both the CPU and custom-built Rasterop video hardware and will normally hold the video information and sound waveform tables. Bank switching is required to enable the 16-bit address bus access to all the Ram. A 4-bit system allows a total address space of 1Mbyte. At least two banks will be occupied by Roms but the rest can befitted with Ram expansion.
The display quality relies on using a 53Kbyte video Ram table. Even at 7Mhz a Z80 could not manipulate this amount of data quickly enough to give reasonable animation, so the custom-designed graphics Rasterop device is essential. It transfers 8-bit data in the video area from one address to another, and in the process can carryout logical functions using data from the destination and source addresses and its own masking registers. Animation and selective screen scrolling becomes an automatic process with the CPU only sending a few instructions during each line interrupt.
Another idea taken from the Amiga is line drawing hardware - the SuperSpectrum will be capable of remarkable 3D wire-frame graphics. The screen mode that will produce the best games has a 756 by 212 pixel resolution and 64 colours. A single byte is used for each pixel, leaving two bits spare for the Rasterop chip to use for Bobs (blitter objects) that give sprite-like animation and collision detection for multi-coloured graphic shapes.
The same principle of Ram sharing will allow sound synthesis of a high quality as waveforms are stored in memory. Sound output, produced by an 8-bit digital to analogue converter, can be heard through a TV speaker, stereo headphones or fed into a hi-fi system. An optional sound sampler will allow you to 'record' any sound that has a pitch and use it as a musical voice. A music keyboard for the SuperSpectrum will be available as an add-on.
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While it's easy to be blinded by the SuperSpectrum's startling graphics and sound qualities there are two other features which could be just as important to the machine's success.
Although the SuperSpectrum will support cassettes - and Amstrad may well build a cassette player into the main box - Softcards could become the new medium for program storage. These credit card size Rom cards can hold a program up to 1Mbyte in size and they are cheap to manufacture.
The other feature which may attract Amstrad to the SuperSpectrum is the built-in CP/M operating system - add a controller and disc drive and the SuperSpectrum fits neatly into the Amstrad range, running the same utilities as the Amstrad CPC and PCW computers.
To give an idea of what might be achievable with the SuperSpectrum take a look at what the Amiga can do. Nearly everyone who has seen an Amiga has had to completely rethink their expectations of other machines. lt can perform lightning fast solid 3D tumbling, animation approaching true cartoon quality and produce digitally sampled sound - real voices, real jet engine roar.
The SuperSpectrum won't equal the Amiga for speed but it will come pretty close, and be able to produce very similar effects at a fraction of the cost.
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The big question is: Will Amstrad market the SuperSpectrum now they have the rights to it?
They'd be crazy not to. With the Sinclair technology and Amstrad's marketing the SuperSpectrum - Loki 'the gamesplayer' - would take the world by storm.