14 Aug
2006
14 Aug
'06
10:17 p.m.
On Tuesday 15 August 2006 00:38, Ethan Dicks wrote:
On 8/15/06, Patrick Finnegan <pat at
computer-refuge.org> wrote:
The extra power has to do with battery life, not power-on consumption.
The amount of power that two cache SRAMs and some buffer chips takes
up is utterly invisible compared to eight set of 4K core stacks (but
you need two OMNIBUS chassis to hold that many cards; a more typical
installation is four 8K stacks or a couple of third-party 16K stacks).
Yeah, I realized that after re-reading your message. :)
Still, if you're just looking for memory, and don't care about battery backup
(like MOS memory replacement), I think that cache SRAM is a reasonable
choice.
Pat
--
Purdue University ITAP/RCAC --- http://www.rcac.purdue.edu/
The Computer Refuge --- http://computer-refuge.org
On Aug
14, 2006, at 8:54 PM, Ethan Dicks wrote:
>> > Why not use a pair of 62256s? 32Kx16 and ignore 4 bits. It'd
>> > even be easy to use a Dallas DS1210 or something like it to
>> > provide battery backup.
>
> 32Kx8 are easy to find as old cache RAM. They are not, however, low
> power, and would not be the best solution if you wanted to hang a
> battery off of them.
I thought the point was to use them in a real PDP-8 e/f/m, in which case
the extra power would probably be a non-issue..