USR quad modems... (ontopic - really!)
zmerch-cctalk at 30below.com
Thu Aug 17 08:15:15 CDT 2006
Rumor has it that Tony Duell may have mentioned these words:
>Hmm.. Both the SAM (CoCo 1 and 2) and GIME (CoCo 3) chips are pretty much
>designed to use DRAM. They output the multiplexed addresses and all the
>right timing signals.
> Surely 41256 DRAMs are not that rare yet?
> It would be a lot easier to stick 16 of those into a CoCo 3 to get it
> up to 512K.
But the *boards* to stick 'em in aren't exactly easy to find, and Cloud 9
(http://www.cloud9tech.com/) aren't building/shipping any more hardware
(including their 512K upgrade boards) until they get the SuperBoard done;
which might be quite a while yet.
Besides - I have bigger fish to fry. This is part of my evil, twisted plot
for world domination!!!
OK, just kidding, but - to venture into where my brain & dynamic memory
part understanding, the 41256 uses a particular refresh
which newer memory doesn't deal with well, so going *beyond* 512K is
problematic. *If* I can figure out how to get 512K of SRAM to work in a
CoCo3, going *beyond* 512K might become a bit easier.
Not to mention - going from SRAM to FRAM would be a pretty easy jump. A
CoCo3 with a "Suspend" switch could be *neat*. ;-)
Or, I might be full of condensed milk, as my father-in-law used to say.
Just my random thoughts for the day...
Roger "Merch" Merchberger
 256 cycle / 8-bit counter / something like that. Did I mention that my
brain doesn't grok DRAM well??? ;-)
 512/1024 cycle / 9-10 bit counter / something like that. Just in case
you didn't catch it, I have DRAMophobia. ;-)
 Now we're getting into the world of PAL/GAL/PEEL/CPLD - which is *way*
beyond anything comprehensible to my grey matter.
Roger "Merch" Merchberger | "Bugs of a feather flock together."
sysadmin, Iceberg Computers | Russell Nelson
zmerch at 30below.com |
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