Replacing SRAM with a SIMM

Hiya folks. I've got a 6502-based project going which uses sram for
system memory and an eeprom for running code. A little more than half
of the memory map is available for eeprom use. I have a bank-switching
method implemented to take advantage of up to 128k of data from the
eeprom, as well.

My eventual goal is to replace most of that eeprom space with more ram,
and make the eeprom only store a basic OS, which would be able to load
software from a drive or something of that sort into the extra memory,
instead of having to reprogram the eeprom every time I want to run
something I write.

The thing is though, roughly 32k of system memory obviously isn't very
much space to work with. I'd like to be able to implement the same
style of bank-switching into this extra system ram, adding maybe up to
512k-1mb of switchable storage capability, to avoid much disk activity.
But the problem is sram isn't cheap, especially when you start getting
into such "large" capacities.

So my thought was to take one of these countless 30-pin simms I still
have laying around and see if it might be possible to use one of those
instead. I know that they're dram, which requires refreshing, but I'm
curious what this would entail, such as what extra hardware I might
need to take care of it, and if it would impact on the normal
functionality of the system to allow for the refreshing compared to the
transparent workings of sram.

I've done a little bit of looking around, but I still don't know a lot
about working with dram in general. Going by a pinout, I don't suppose
I really need the parity bit and such, unless you're required to use
it. Some simms don't even use parity from what I understand.

Anyhow, this seems like it might be the cost-effective solution, if it
can be implemented without affecting how it already works very much.
I'd certainly appreciate any input anyone has to offer.

.

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