Publisher: John Kortink
Compatibility: Acorn Electron
Reviewed by: Dave E
Originally published in EUG #67


The GoMMC expansion by John Kortink was released for the BBC Micro, Master 128 and Master Compact late in 2002. A small PCB board that fits under the hood of a Beeb machine, its main aim is to eliminate the need for any and all disc drives and allow you to have 'virtual' copies of every single disc (both ADFS and DFS) available, at the touch of a few buttons. It does this by what should be a very simple procedure for anyone who has ever downloaded a disc image (i.e. one of the .ssd, .dsd or .adf files). You simply buy a 2Gb Multi-Media Card (MMC), more commonly used with digital cameras and mobile phones, plug it into your PC, enter a line to convert the disc image file to the GoMMC format, remove the MMC and plug it into the MMC board on your trusty Beeb and call it up! No whirring disc drives, no huge piles of 5.25" discs threatening to devour your family. No, instead, everything immediately available, all invisbility tucked away inside your keyboard.

The BBC GoMMC has been available for several years but alas, the Acorn Electron was not manufactured with the same internal upgrade possibilities, and demand for an Electron version did not surface. As we are almost solely a site for Acorn Electron disc images, this was something of a disappointment. We even contacted John Kortink at the time to enquire into whether it might be possible to make a GoMMC for the Electron and got back the enigmatic reply, "It would be fraught with problems" which seemed to dash that dream.

However in what just might have been the most exciting development of the year, John Kortink suddenly advertised last year that, if he could secure at least five orders for Electron GoMMC in advance, he was fairly confident of bringing the addon to Electron owners. Bring it to us he did and, with a measureable degree of frustration, we have now got an Electron with Electron GoMMC running. This is more an introduction to it rather than a review however because, even after four days of experimentation, and reading all the documentation from cover to cover, there are both bugs and missing essential components that would allow us to load and run discs from different filing systems. As we bought one of the first units 'off the production line' then it may be that subsequent purchasers will not encounter many of the problems we have had but with this article we hope to illuminate, at least, how Electron GoMMC is sorely let down by its documentation.

To start from the very beginning, the announcement that Electron GoMMC was coming came on an e-mail from its Netherlands-based manufacturer which invited us, for 65 Euro to place an advance order by Paypal. We did so, at once, naturally enough to the e-mail address the mail had come from. Kortink then wrote to us to say he had not accepted the payment as he would like it sent to an alternative e-mail address. Not a particularly customer-friendly start, as it meant we then had 65 Euro in our Paypal account not gaining any interest for several months, as Kortink wanted the money now so that he could commence work, and so it was necessary to do another 'Paypal instant bank transfer' of 65 Euro to the new e-mail address, while the transfer back to the Paypal account of the first transaction remained 'pending'.

Kortink then set to work on the units, and several months later, announced Electron GoMMC was completed, and could be shipped with (a) two sideways ROM banks, (b) two sideways RAM banks, (c) eight sideways ROM banks, or (d) eight sideways RAM banks. There was no explanation of what these banks may or may not be needed for, so we plumped for (d) as it was the most expensive and so, we assumed, the best. At this point, Kortink also asked for more Euros to pay for shipping so, all told, the interface cost around 90 Euro (£55.00). Another trip to Paypal and our Electron GoMMC was on its way. We will now catalogue the previous four days as we struggled to understand how to use it.

Day 1

Electron GoMMC arrived in a small box, securely packaged up. Inside the box were, individually wrapped:

1)Two ROM chips (28-pin), each labelled 'Electron Toolrom 1.02'
2)One GoMMC interface
3)One Electron Expansion interface
4)One ROM holder with jumper cable
5)One ROM holder without jumper cable

There were no instructions on what any of these things were for, or how they all fitted together. Although it seemed fairly obvious, say, that the 'Electron Toolrom 1.02' should be plugged into either the GoMMC or the Electron Expansion, there was no free ROM socket available for it! GoMMC and the ELECTRON INTERFACE fitted together snugly to create Electron GoMMC but left no room for any of the ROM holders or either of the two chips.

Firstly, therefore, we e-mailed John Kortink to ask if there was an idiot's guide to putting it together. He responded by saying "I did send you instructions" (He didn't!) and directing us to his web site which featured an 'installation guide' (in html format). An hour spent scrolling up and down this guide and we were none the wiser, apart from realising that we needed to buy an MMC and the large 32-pin ROM already installed inside the Electron Expansion interface should be removed and replaced with the Toolkit 1.02 ROM. (Had we not done this, we might have progressed much more quickly, but this is what his site said.)

Day 2

Not all MMCs are compatible with Electron GoMMC so we spent a morning wandering around mobile phone shops, photographers and Woolworths searching for a Kingston 2Gb MMC card. Rather unhelpfully, John Kortink's 'installation guide' noted "If you bought your MMC from me, it will come pre-formatted and will, of course, be compatible with GoMMC." It would have been nice to have been given that option at the time of ordering! Finally we found a Kingston 2Gb MMC card, got it home and plugged it into Electron GoMMC. Further reading regarding installation was necessary and - lo and behold! - we discovered the two ROM holders, both the one with jumper cable and the one without it, were completely unnecessary if GoMMC was to be installed on an Electron!

At first, we wondered exactly why John Kortink had enclosed them. Unless he was trying to confuse his customers, there seemed absolutely no point. Finally, we concluded that, by including them, GoMMC could be installed on all of the BBC computers, as well as the Electron - so he was probably just thinking that if at some point in the future, we wanted to transfer our GoMMC to a Beeb, we would have the extra parts needed to do it. This was another reason though, why the physical package needed an idiot's guide! If you send people five parts and no instructions, they naturally enough think the five parts fit together in some way, not that two of the parts are superfluous and they should start chiselling out 32-pin ROMs and sticking in 28-pin ROMs, and going shopping for a MMC card, before they start!

The whole GoMMC experiment was becoming decidedly frustrating by this point but it was about to get a whole lot worse. John Kortink's website now instructed us to download the 'GoMMC tool package' which needed to be installed on our PC and which included the 'operation guide'. This came as a plain text document which needed to be cut and pasted to Microsoft Word, then selected and reformatted to Courier New, font size 10 and which then weighed in at 46 full pages. Thank goodness though, it began by saying:

'This guide has a basic and an advanced section. The basic section attempts to describe basic use of GoMMC only, and hold back on details. If you're a first time user of GoMMC, or an advanced user looking for only basic information, read this section.'

Working through it methodically, the next step was, naturally enough, to format the MMC installed in Electron GoMMC. To our surprise though, the manual referred us forward three pages at this point to the section 'Running GoMMC tools' which then proceeded to list four different ways of doing this. The first one, was headed 'Via floppy'. This is nigh on impossible with an Acorn Electron, as Electron GoMMC plugs into the back of a 'bare machine', attaching to the expansion connector. There is no throughport on Electron GoMMC and therefore, unless you have the official Acorn Plus 3 L-shaped interface, you are not physically going to be able to attach any floppies at all!

The second one, 'Via ToolROM' looked promising, as we now had both the TOOLROM 1.02 ROM, and our MMC, installed in Electron GoMMC. However, many of the commands of Toolrom cannot be accessed with the *HELP TOOLROM that you might expect. No, instead you must type:

*OPT 1 2

After doing all this, the catalogue did indeed show the command for formatting the MMC: *MMCFO. But we were rather put off by the subsequent sentence:

'For more information refer to 'Tools: TOOLROM' in the advanced part of this guide. Read this carefully, and in particular take note of the caveats!'

Less than fifteen minutes of starting to read the basic section and we were into the advanced section, which now informed us there is 'a serious bug' in OS 1.20 when *RUNning files under the ROM filing system and we should have typed:

For f**k's sake!!! All this flipping around in the manual also meant that we frequently lost our place and line of thinking. And we had printed out the manual; trying to follow it on your PC screen would be even more infuriating. Our mission was simply to format the MMC card which, by traversing these three sections, is actually done with the rather easy command:

Finally, we managed to format the MMC and it seemed the oversight above had not corrupted it. However, as we found out on Day 3, there was actually a much easier way of doing it! We could have just used our PC!

Day 3

By now, we had spent about ten hours or so twiddling with the manuals, downloads, .zip files, cataloguing and Toolrom that make up Electron GoMMC. Today we awoke determined that we would get some actual disc images onto Electron GoMMC. Option one to do this, once again, said we could use a floppy, which as we noted above, is not possible on the Electron. Option two sent us back to our PC (Windows XP only) and the utility program 'GoMMCio' which was in the batch of tools we previously downloaded (Sigh!) from the website. To do the transfer, you do of course need a MMC drive on your PC, and to have moved your MMC out of your Electron GoMMC and inserted it into your PC.

The operation guide sent us forward to yet another section: 'Running GoMMCio' which was surprisingly easy to follow. Certainly the exception rather than the rule. We successfully converted EUG #0 (the ADFS version eug00.adf and the DFS version eug00.dsd) and stored them on the MMC in minutes.

The next step however, 'Running a patched filing system', had us swearing like dockers! First of all, yet another trip to cyberspace was necessary, this time to download all of the patched filing system files which need to be put onto the MMC. From these files, you need to cross-refer to the guide to discover which filing systems are required (i.e. which work) on the Electron and then use another tool (flipping around in the manual again) via GoMMCio to write these to the MMC. This bit we finally achieved (after approximately two more hours).

The manual then instructed us to move the MMC back to the GoMMC on your Electron and use a bewildering succession of commands to instruct Electron GoMMC to auto-configure it to load in the filing systems from the MMC and store them in Sideways RAM. Well, there is only one ROM socket on Electron GoMMC and, seeing as that now remained occupied by the Toolrom ROM (from yesterday's formatting), after much frustration, (wondering how we could write to Sideways RAM when there was no Sideways RAM to write to!) we realised we now had to lever out the 28-pin Toolrom ROM and put back in the 32-pin ROM chip it had in at the very beginning!

With our Electron installed with Electron GoMMC and the 32-pin ROM chip powered up again, it suddenly became obvious that this chip did not contain 8 banks of Sideways RAM! John Kortink had shipped us an EPROM already programmed with the patched version of Acorn ADFS. Which is great... if only he'd f***ing told us! And of course, a patched ADFS EPROM only allows you to run ADFS discs. Unfortunately, the vast majority of the disc images in Acorn Electron World are DFS disc images (because ADFS takes much more of the Electron's memory to run).

However, with a patched filing system on EPROM and the converted disc 'A-EUG00.adf' in the MMC, we had sort of blundered into territory where we were finally ready to load and run a disc from MMC. Surely how to do this would be listed in the Basic section of the guide? Wrongo! Incredibly, these important commands are buried in the middle of the Advanced section! They are listed almost like the index of, say, the Acorn Electron Plus 3 User Guide, with no tutorial in their use whatsoever. Mystifying, especially as they are, once you find them, simple to use.

The most irritating aspect of this discovery by far though was, after almost 30 hours of to-ing and fro-ing between manuals, internet site, PC and Electron, we had discovered that, in fact, were the manual written correctly, it could have simply stated: 'Your Electron GoMMC is installed with a patched version of Acorn ADFS. You need to buy and format an MMC card on your PC and add some disc images to it then put it into Electron GoMMC. The following command will then list the discs on the MMC: *MMCLIST. And the following command will select a disc: *MMCDISC A-EUG00.adf. Then boot the disc as normal, using SHIFT-BREAK.' With such an explanation we could have been good to go in a few minutes!!

Day 4

On Day 4, finally we could witness the power of Electron GoMMC. At the moment, as indicated above, we only have the power to read ADFS disc images [So it's quite lucky that we did all that conversion work back in 2002 to get lots of games onto ADFS, n'est-ce pas? - Ed] but the results are, quite simply, breathtaking. An Electron GoMMC-enabled Electron operates completely noiselessly, just a little bit quicker than a floppy drive and, in all other respects, it is completely comparable.

But there was one final heartbreak in store: All the Acorn Electron World discs and all of the EUG discs use a machine code program to display any ASCII text (i.e. all articles, reviews, solutions, etc) which clashes with Electron GoMMC, meaning, whilst many of the games themselves work on Electron GoMMC, you cannot view any of their instructions, reviews or solutions. Whilst this is not a particular problem in that these days all this information is duplicated on the Acorn Electron World web site, it does rather diminish the content of anything that you download. Anything you spend the time converting to your MMC hangs with an error if you try to load any ASCII file! It's also worth noting that the ADFS versions of Elite and Exile do not work on Electron GoMMC which will be an obvious disappointment to anyone thinking of buying one at this stage.


Without an 8 bank Sideways RAM chip installed instead of the patched ADFS ROM one, our comments run out at this point. Because of the bug with the ADFS discs, we feel the interface, and definitely its documentation, is still at a prototype stage therefore our verdict on Electron GoMMC can wait until a future issue and a 'real' review. Perhaps when we get the Sideways RAM and work out how to configure it to auto-load the DFS filing system, and run our DFS discs, we will be able to report 100% compatibility. For now, although we feel we have glimpsed the future with Electron GoMMC's easy selection of discs and massive storage potential, we remain decidedly lukewarm. The interface is far too difficult to use and, without a complete rewrite of the manual, many people will give up in sheer frustration long before they reach the stage where they could see it in action.