The same functions with the same wiring, only in SMD

I count only 8 pin on the red and 10 pin on the green,

and the red one does not seem to have a connector on the right side either ...


That does not seem the same ... where am I wrong ?

Here is the explanation

Ok, I did not remember, that the pins of the former cable are separated,
so those can be connected (physically) in any order to a board (former or new one) ...

It is annoying.... I was meaning the same signals there.

Ooops
I looked the memory map with the new (red) board, and it is look very crazy
Then found the suggested wiring on Szörg's page are wrong, two wires need to be replaced.
There is the updated table:
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Universal cable which can be used with both Saint and Kotek type boards:
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With Saint board:
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With Kotek board:
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Memorymap of the new red board (Kotek):
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Don't forget - the custom chip are on the board, not only Z80...

Also to make the design even easier you can connect the data lines to the SRAM chip in any order.

And the address lines to the RAM chip can also be in any order. The only addresses that can't be swapped around are the ones you're using for /CE.

Does that make sense?

Don't follow this if you later want to add some FlashRom to your expansion.

Absolutely! But ... if all that someone is interested in is a simple RAM expansion, then I believe that the suggestion is a good one since it might make routing the traces easier.

Heck, with SzörG's lovely SDcard interface and enough RAM, then modern users might not even see much need to ever add some FlashROM.

It all depends upon what each individual owner wants to do with their Enterprise.

I am trying to search the gerbers of Saint's Ram expansion(asking him...). Or the ones of the Spanish clone(I still have not contacted  "Quest", the guy that copied it). If not found, don't you think it is easier to not reinvent the wheel? the layout seems very easy to design on Eagle or other similar program.

I have absolutely no interest in "reinventing the wheel", nor do I believe that I have the knowledge, experience or skills to somehow invent the "best" internal RAM expansion.

I just want/need an internal RAM expansion for my Enterprise 64, and none seems to be currently available anywhere for me to buy, so I am trying to come up with an *easy* solution that requires minimal soldering or programming, that might be easy and cheap to order, and that hardware-novices could re-order themselves in the future.


When it comes to Saint's lovely design ... the GAL that he used has been obsolete for some time, and they mainly seem to available as "used" units from China. I can find some sellers of NOS parts, but they are 20x the cost of a surface-mount 74HCT138 from JLCPCB.

Other 5V GALs, such as Atmel's ATF16V8B, are still widely available and affordable, but then that would be a change in Saint's design, and I don't know if that would work.

Then, whichever GAL is used, someone has to have the right equipment, and then take the time, to program it.


You, Saint, Kotek and others have far more hardware knowledge than I will ever have, and if you, or someone else produces some boards (of whatever type), then I will probably buy one.

But if not, then is there some reason to avoid the simple 2-chip solution that I am suggesting?

With my limited knowledge, it seems to be almost identical to what both @dangerman and @Zozosoft have already had working, and have shown in other threads.

I think a simple external RAM expansion connected to the right side port of the computer would be nice as well, without needing to solder and modify the original HW. I know there's the SF3 card, and Pear's Dream Turbo Card, but combined with the SD-card reader connected to the cartridge bay, it would be enough for most users (and much more cheaper I suppose).