| ★ HARDWARE ★ SUPERPOWER BOARD ★ |
SUPERPOWER BOARD (Amstrad Action) | SUPERPOWER ROM CARD (Computing with the Amstrad) |
THE Superpower ROM card from Micro Power allows seven additional ROMs to be added to the Amstrad CPC464. It can also be used on the CPC664 but requires a bus expander to connect correctly. If you're not familiar with the advantages of ROMs then here's some information you may find interesting. ROM-based software only requires a small amount of RAM for workspace. Thus, much more memory is available for data than with programs on disc or tape. This is because the program doesn't reside in the main RAM block but in a ROM just like Basic. So if you find the Amstrad's memory rather limiting, ROM-based software may provide a solution. At present there aren't many ROMs available for the Amstrad. But if the BBC Micro is anything to go by there will be about a hundred ROMs available for the Amstrad this time next year. Since the Amstrad can support well over 200 ROMs it should be interesting to see if anyone produces a board which can cope with the maximum capacity. One thing worth bearing in mind is that you'll have to be prepared to pay between £25 and £50 for each ROM . . . Fitting the Superpower ROM-card is a simple task as it connects to the expansion port at the rear of the Amstrad - no awkward soldering required. If a disc interface is present it is slotted into the back of the ROM box in piggy-back fashion. The ROM card is mounted in a grey plastic box which matches the Amstrad's case very well. The inside of the box can be examined simply by separating the two halves of the casing. This reveals a neatly-laid-out circuit board containing four logic ICs. seven 28-pin sockets, seven address links and an edge connector. Each ROM, which can be either 8 or 16k, has a ROM select number which is determined by its socket position on the board and the setting of the ROM's link. However, the operating system requires the ROMs to conform with several rules. These concern the socket numbers and position of foreground and background ROMs. A foreground ROM, such as Basic, is capable of taking total control over the machine. A background ROM is designed to be used from a foreground ROM to provide extra facilities. For this reason it is usually known as a service ROM. In fact, the only problems I had with the ROM card was sorting out the link settings to ensure the various ROMs conformed to the rules. The instructions weren't very clear on this subject - however the documentation I had was only provisional. Once the ROMs have been installed and the links connected, the unit can be plugged on to the expansion port. When the Amstrad has been turned on, the ROMs will be active and ready for use. As it stands, the Superpower ROM board is very easy to fit and will be perfectly adequate for most people when they want no more than seven ROMs - and there aren't that many written yet. What I'd like to see is a larger capacity board, with RAM. With such a board. ROM-based software can be loaded from disc or tape into a special section of RAM and will operate exactly as if it's a ROM. If this happens, the price of ROM software could be almost halved because the expensive ROMs, and EPROM programming time, are no longer needed. Still this is all pie in the sky. If you're only going to use up to seven ROMs - and who can afford more? - the Superpower ROM-card is perfect. Kevin Edwards , CWTA |
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