Eprom board?

[Wicksy]

EDITED!

Hi, am wondering if anyone would be interested in building a plain 128k eprom board with IC sockets and through connector (Qflash spec)- which I'll pay for?

[jobdone]

this is my thought why go for 2*64Kb roms when you could use a larger rom and bank switching?

[Wicksy]

Yes true.

[RalfR]

Hi, am wondering if anyone would be interested in building a 128k eprom board with a difference - which I'll pay for?

Hmm, I'm not so sure what you actually mean. There were already Eprom cards for three 64k Eproms that were plugged into the expansion bus, for example from Sandy in Italy, but also from other manufacturers.

I used a card like this that had toolkits, Q_Liberator and other things in it. I was then able to start the programs with keyword.

[Wicksy]

Am looking at a board where the roms are easily interchangable by using the rom cartridges we all know well, but mounted on an expansion slot board. One board with a few cartridges with different applications or utilities.

Failing that a traditional board.

[jobdone]

Ok where I stated 64Kb, it seems I may have done the classic assuming problem. 64KB so 512Kb roms.

[Wicksy]

Am aiming at the 256k area reserved for rom.

[Dave]

The easiest way to accomplish this is with a 128Kx8 SRAM and a CR2032 as backup power. The battery would hold the contents in SRAM for around two years of standby time. A jumper could enable or disable the write lines to protect the ROM images.

One refinement would be to have TWO CR2032s so they last 4 or 5 years, and you can swap one then the other and not lose data swapping the battery. Otherwise, you'd lose data during a battery swap, or you'd have to freeze the card before doing the swap in under 30 seconds.

[Dave]

Extending on this idea, bringing out a separate write protect switch out to the front so there were 4 dip switches, you could have a ROM image in one slot and RAM accessible in the other 3 slots, giving you a nice 48K spot to stick data or an executable or whatever. A ROM slot like on the back of the QL could be placed on the edge too to finish off your requirements.

[Wicksy]

Yes, I see a mix of the battery backed ram and a rom cartridge mix Dave.
EDITED my first post to a more simple idea.