Looking for information on a QUAD width omnibus RAM card.
Not interested in hex wide as it doesn't fit the older
Omnibus 8E or F boxes. I used to have a 4kx12 card that
used 2102 type rams but had no data for it. That went to
and earlier 8E I had.
Even schematics would help. In the end I may do my own as
a pair of 61256s will certainly fit the bill and barely fill
a corner of a board.
Allison
I ran across this front panel; does anyone know what it might have gone to? FYI,
the file is about 1 MB in size.
http://www.rain.org/~marvin/frtpanel.jpg
I was told this came from Lobo Drives, but I can't imagine what they might have
used it for. The markings on the left are not clear in the photo. The box is
labeled "Register Select", the left column is marked "Display", and the right
column is marked "Enter". The 18 position switch (0 - 17) is marked "Register
Select", and switches are marked with such things as "Rosar", "Start Address",
"Stop Address", "Spare Address", etc., and the top lamps look like maybe
register contents and are marked CA, CB, CV, CK, CN, CH, CL, CW, etc.
I've decided to try out the Data General emulation in SIMH and am
looking for software. Is there any place that has software for RDOS
like extra programming languages, games and productivity-type stuff?
If not is anybody willing to share?
Mike "Madcrow" K.
>
>Subject: Re: PDP-8 /e/f/m memory
> From: "Roy J. Tellason" <rtellason at verizon.net>
> Date: Tue, 15 Aug 2006 12:33:20 -0400
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On Tuesday 15 August 2006 08:26 am, Allison wrote:
>> I shave off the top of the DS1287s and replace the cell. It's easy to find
>> the battery on those as it's magnetic!
>
>Interesting! What tooling do you use to do this?
>
The 1287s I did this to were made with a second layer of plastic over the
origninal 28pin dip. Simple problem to grind through the plast to the
battery, remove it and solder leads to the remaining connections.
At various times I've used, hot soldering iron, belt sander, coarse file
to get down to the battery. Rude and crude ut then again I the chip was
bad already so it wasn't like I was going to loose anything.
Allison
Hi,
I usually don't bother compressing TIF's of scanned
images -- since I'm not too concerned with saving
space for small documents.
But, recently, I started scanning B-size drawings
(e.g., print sets for projects I've worked on).
Usually, I have to scan these at higher resolutions
(because I often print B size versions of D size
drawings :< ).
The larger sheet size and higher scan resolutions
are starting to make single sheets quite *large*!
Suggestions? I had thought of FAX encoding (naive
but it should work well on line drawings/schematics)...
Thanks!
--don
>
>Subject: Re: PDP-8 /e/f/m memory
> From: "Ethan Dicks" <ethan.dicks at gmail.com>
> Date: Wed, 16 Aug 2006 12:23:43 +1200
> To: "General Discussion: On-Topic and Off-Topic Posts" <cctalk at classiccmp.org>
>
>On 8/16/06, Bob Rosenbloom <bobalan at sbcglobal.net> wrote:
>> The 5 volt parts have a write cycle limitation that's
>> not there with the 3.3 volt parts.
>
>Ah... I did not know that 3.3V FRAMs were substantially longer-lived
>than the original 5V versions. I'm still in favor of a pair of 62256s
>(since they are so common and very cheap), but if I were to do an FRAM
>board in the future, it's probably worth the extra buffers and
>regulator to get chips that will last.
I'd not use FRAMSs for PDP-8 as the need to write the subroutine return
address at the begining of the subroutine would beat up some locations
a lot. Also the write cycle does have delays while writing goes on.
A better use for FRAMS is disk emulation. Lower number of write cycles
but lots of reads. A few of them could easily emulate a RK05f. Even a
pair of 32k SRAMS can emulate an RX08 (only faster!).
One forgets that a PDP-8 system with a few megabytes of storage is a BIG 8!
When you consider that SRAMS ar available to the 512kbyte range or larger
and the prices are low. It's very easy to consider semiconductor disks
in the megabyte range. If you resort to using DRAMS I have a pound of
30pin 1mb simms that easily could be used for a large disk simulation.
Allison
>
> From: "Al Kossow" <aek at bitsavers.org>
> > http://bitsavers.org/pdf/msc/MSC3102_PDP8semiMem.pdf
>
> That one is much clearer, though I cannot find the logic in it
> (if any) that inhibits reads when using the bootstrap cards.
The bootstrap ROM in my 8/e is a diode matrix ROM that doesn't appear in
the memory map. When you flip the 'SW' switch, the boot ROM pretends to
be a front panel and copies itself into the appropriate bit of core.
-tony
--- Bryan Pope <bpope at wordstock.com> wrote:
> And thusly were the wise words spake by Dave McGui
re
> >
> > On Aug 14, 2006, at 3:38 PM, Ray Arachelian wrot
e:
>> snip <<
> >
> > Yes, and fortunately, they all have power
> switches. ;)
> >
>
> That is, until they use power from *you*... Anyon
e
> remember
> B.A.T. for the Amiga? (
> http://www.lemonamiga.com/games/details.php?id=128
)
> The character you played had a computer implanted
> into his wrist.
>
> Cheers,
>
> Bryan
>
Thanks for the link to that site. I managed to
look up US Gold and saw quite a few games
that I actually have for my Spectrum (e.g. Gauntlet
2 & 3) and one of the best games of all
time IMO - Flashback, which I have for the
Sega MegaDrive.
Regards,
Andrew B
aliensrcooluk at yahoo.co.uk
Re:
> But doesn't JPEG use lossy compression?
>Yes. And it blows thick industrial-waste chunks on any
>graphics that are non-photographic.
>Peace... Sridhar
Bull
Take a look at the stuff I've scanned on Howard Harte's site, including
schematics, for example this one:
http://www.hartetechnologies.com/manuals/Cromemco/Cromemco%20Bytesaver%20II.
pdf
They are fine. Keep in mind that almost every PDF file that was produced by
scanning is a JPEG internally. Sure, there are lots of such files that are
crap, there are lots of bad scanners (referring to both the hardware and the
people that use them). But there are also some that are excellent, superb,
indistinguishable from the original. And since they are all JPEGs, JPEG can
do this with no discernable compromise IF YOU DON'T TRY TO OVER-COMPRESS.
[The schematic in the Bytesaver manual was almost unreadable in the original
printed format, extremely fine, extremely faint lines, but take a look, for
example, at the drawing on page 10 of the manual (page 12 of the PDF file).]
