outgrowth of : OT: how big would it be? - test-drb@ccmp.vtda.org

20 Oct 1999

What I'm really after is small RAMs with separate ins and outs, and the
current generation stuff doesn't seem to address that requirement.  I guess
I'll have to use a CPLD or FPGA with RAM inside.

Dick

-----Original Message-----
From: Tony Duell &lt;ard(a)p850ug1.demon.co.uk&gt;
To: Discussion re-collecting of classic computers
&lt;classiccmp(a)u.washington.edu&gt;
Date: Wednesday, October 20, 1999 7:22 PM
Subject: Re: outgrowth of : OT: how big would it be?

...
 >
> So, who makes 256-byte RAM devices at TTL speeds these days.  There are all
...

Good question... All sorts of useful, generic, devices are no longer
made. Oh, there are millions of complex chips for particular
applications, but just try getting a small RAM, or a simple UART, or...

  sorts of FIFOs of 256 bytes, but I can't find
a simple 256-byte RAM any
 more.  I also need a 32x8-bit sram, fast (preferably address-access time
 <<10ns) and preferably in a small package. 

Remember you can always use a larger static RAM that you strictly need
and just tie the unused address lines to a defined state (e.g. ground).
So possibly you could use the same chip for both problems.

What about the cache RAM off a PC motherboard (is that still being made?)
It was pretty fast (15ns or better?), and 32K*8 skinnydips were used I
think. Or am I a year out of date again?

-tony