DK tronics plugs you in to that wasted RAM - Andrew Wilton checks the is claims.
With this new plug-in DK'tronics, a firm best known for offering add-on memory expansions, are going into the business helping you use the memory you've already got. If you've got a 6128 , you've got an extra 64K of memory compared to 464 and 664 owners. But unless you use CP/M Plus this 64K probably hasn't done you a whole lot of good up till now. The 64K Silicon Disc just might change that - for a price.
Like its 256K big brother, reviewed in the May issue of AA, this package Offers you a ramdisc for your CPC. A ramdisc is a section of memory which behaves like a disc drive: you can save and load files just like a real drive, only much faster. Unlike the 256K version the new Silicon Disc, or sDisc for short, doesn't actually come with RAM of its own. It simply enables you to use that extra 64K of RAM as a ramdisc, something it wouldn't be too easy to do otherwise.
The sDisc is a single unit which plugs onto the expansion port. As such it makes a much more reliable connection than that the twin units, of the 266K version. There is no noticeable wobble on the unit; and it behaves well even with quite a few other peripherals hanging on the through connector. The only connection problem came when I tried to connect it at the same time as a Pace RS232 interface - and there was a good reason for that , as we'll see later.
Once you've got the sDisc plugged into the back of your Arnold you can set the thing up for use under AMSDOS. To do this you simply type the external command |SDISC. The sDisc ROM responds by telling you which drive it's going to be; drive B tf you''ve bare 6128, or drive C if you'ye got an drive as well. If you want to use it in the normal AMSDOS way, you can now switch to it using |B Or |C as appropriate- The commands CAT, |ERA and the like will all work just as if you were dealing with a genuine disc drive.
You can also use the 64K sDisc with CP/M 2.2 from side 4 of the 6128 system discs, but you'll have go Jw 3 bit itiore ; trouble. It's allj set out step-by-step and there's nothing too hard about it so long as you follow the instruction but you'd have to be pretty well up on CP/M to have the faintest idea what it all means.
If the reliable connection made a pleasant change from the old th old 256K Silicon Disc, there are several minus points worth bearing in mind. An obvious one is the srnaller capacity. Once you've made room for the directory there's only available, and that's really not very much at all. If you want to run an application from the Silicon Disc and keep data on the normal other 72 pages; they make pleasant enough reading and do no ; herm, though the packing was designed with a thinner manual in mind and makes for a bit of a tight fit.
To their credit, DK'tronics ate: at pains to point out the incompatibility of the sDisc with CP/M Pius. The only thing that the manual lacks is a mention of the thing's ROM number. It is in fact ROM number 4, so you won't be able to plug it in with the Pace RS232 for example
If the review has been a bit on the negative side so far, that's because I've left out the most important factor - the price. At just under a hundred pounds the 256K version was, 1 felt, somewhat overpriced. Cheap non-Amstrad drives make this look even more the case now.
With its sub-thirty pound price tag, the 64K model is a much more attractive proposition. If you can't afford a second drive for your 8128 this new ¿Disc does represent a viable low-cost alternative, it's got a very low capacity and it can't do some of the useful things that a real drive can do - make back-ups, tor : example - but it is both cheap and fast.
Andrew Wilton, AA