18 Apr
2017
18 Apr
'17
4:01 p.m.
Found this file on an old Rainbow floppy. It has more detailed data.
http://people.freebsd.org/~imp/RBMEMRY.TXT
Sorry I didn't convert it to HTML...
Warner
On Sat, Apr 15, 2017 at 7:49 AM, Tapley, Mark via cctalk
<cctalk at classiccmp.org> wrote:
On Apr 13, 2017, at 3:20 PM, Warner Losh via cctalk
<cctalk at classiccmp.org> wrote:
On Thu, Apr 13, 2017 at 12:00 PM, shadoooo via
cctech
<cctech at classiccmp.org> wrote:
I?m pretty sure the PC100A takes the same board. I believe I have a 100A set up like
that, but I?ll have to check when I get back (from vacation) in a week or so (unless you
get a definitive answer before that). Meantime if you spot one of those boards, obviously
it would be good to grab it; sounds like there are 100B users on-list who would be happy
to give it a home if I?m wrong about it working in the 100A.
Meantime, from my Rainbow Technical Manual copyright 1984 scan (ask, I have a
fair number of these documents) which says it refers to model PC100A:
Rainbow Memory Extension Option Installation Guide: EK-PCMKE-IN
?Two versions of the memory extension option are available: a 64 K byte option (part
number PC1XX-AA) and a 192K byte option (part number PC1XX-AB). The memory option is
installed in the J6 connector ?
? Both versions of the memory extension option use the same printed circuit board
etch and the same type of 6kK x 1 bit memory chips. ? the 192K byte version contains
twenty-seven 64K x 1 bit chips arranged as three 64K byte memory stacks. ...
From my Rainbow Owner?s manual 1st ed. Sept 1983, Appx. C, Table C-1
?
64K byte memory board option: PC1XX-AC
256K byte memory board option: PC1XX-AD
64K byte memory component kit (9 chips) PC1XX-AY
256K byte memory component kit (9 chips) PC1XX-AZ
?
Hope this helps. Hello,
I'm in the pretty same condition, I have a Rainbow 100B without memory
expansion.
Not sure however, about the correct board number, which would fit the 100B.
What should I search for?
The DEC part numbers for these are PC1XX-AY (128k) and PC1XX-AZ
(256k). I'm not sure what the board numbers are, and some auctions
list those instead.
They are the same board. There's 4 switches on the board. One for each
of the 3 banks to select between 64kbit chips and 256kbit chips. You
want 4164 or 41256 for the board. It's super easy to upgrade (I bought
a AY back in the day and then 18 months later I bought 27 41256 chips
and swapped them out in about 10-15 minutes.
I'm not sure what the 100A needs. I have no experience with the 100A hardware.
Warner