Well, somebody had to do it and it's Slogger who have taken the plunge and committed themselves to producing Shadow RAM for the Elk by the Acorn User Show, held at the end of July.

As well as providing a huge 28K of free memory in any Mode, the speed of the Electron is increased in the same way as achieved with the Slogger Turbo Board (reviewed in A&B April 1986). This means speed increases of up to 100% for all operations and as much as 300% for graphics orientated programs.

The Shadow RAM is even more useful to the Electron owner than it is to the BBC user. The least greedy Mode on the Electron is Mode 6, eating up 8K. BBC programmers have always been able to fall back on Mode 7 - the 1K Mode.

The least greedy graphics Mode is Mode 5 - taking 10K - and the top three all take 20K each.

The difference is also most noticeable when considering applications such as word processing. Starword in 80 column Mode is severely restricted by the size of document it can hold in memory. With Shadow RAM, there are 28,000 bytes free for text. View is similarly affected.

As with all BBC Shadow RAM systems, the RAM is a block of 32K. Since 20K is all that is required to act in parallel with the screen mapped in main memory, 12K is left over. Various systems have used this 12K on the BBC in various ways. The extra memory is put to excellent use, for instance in the Master, and is one of the main differences between that machine and the B+ 128.

At the moment, we know that Slogger have supplied built-in printer buffer software to cut the computer time wasted when printing a long document. The buffer absorbs the text and queues it for the printer while you get on with something else at the keyboard. There are many other possible uses for this extra RAM and they should emerge during the rest of the year. A full treatment of Shadow RAM can be found in October and November 1985 issues of A&B.

Details about the 64K Electron from Slogger on 0634 52303.