[sdiy] Understanding upgrading SRAM in the 606?

[Rob B.]

The piggybacking idea works, you just have to reroute the Chip
select/read/write lines using a switch. I have thought about it, but haven't
done it yet for my 606.

I assume the 303 is roughly the same.

Rob
----- Original Message -----
From: "Plutonique9" <Plutonique9 at symbiocom.com>
To: <synth-diy at node12b53.a2000.nl>
Sent: Wednesday, May 02, 2001 3:32 AM
Subject: [sdiy] Understanding upgrading SRAM in the 606?


> Hey there,
> I wrote about this a little while back, and someone sent me a link to
> a schematic detailing an idea for a 32 bank 303 memory mod, not Robin
> Whittle's though.
>
> I'm eager to learn on how the memory in these X0X's work, as both the
> 606 and 808 desperately need more pattern data storage.
> I don't want to go the big 32 bank mod yet, I'd even be happy with
> just doubling the amount of space. I've tried reading up on SRAM, but
> I can't find any information that is relevant to understanding how to
> increase the banks in these X0X's, or really any instrument for that
> manner.
>
> Is it possible to "piggy back" SRAM on top of the existing memory and
> have some sought of toggle switch which chooses between which SRAM is
> being used? When you push the bank number "I/II" on the 606, is this
> just switching between the 2 sram chips onboard, or are they both
> used in both mode "I" and "II".
>
> I'm sure it is not as hard as maybe I think, but if someone could
> point me in the right direction in reading up on this subject, or if
> the could clear up some of the "logic" behind how the memory works in
> these machines, meaning what the how the Pins are used to select
> different banks, etc. I'd be dig it extremely. It is a very confusing
> topic to the new comer, much different from straight forward sound
> modifications, but I feel this is only because of a lack of resources
> on information on the subject.
>
> Anyways thank you, and could whoever sent me that 303 memory upgrade
> schematic link, could you please forward it to me again.....:)
>
> Seeya
>
>
> -- Plutonique9, Plutonique9 at symbiocom.com
>
> http://www.mp3.com/Plutonique9
>
>