>>> In hindsight, could the DEC-20 or RISC version of it
>>> had marketing and other bad luck changed ,and
>>> today replaced the PC in many applications?
>>
>> Six bit based architectures all died with the rise of the IBM S/360
>> family. DEC, CDC, Univac.
>>
>> It also did not help that many of these old line mainframe
>> architectures were getting hard to extend. For the DEC 36 bitters -
>> what does one do after the 18 bit address pointer, with two neatly
>> stuffed into a 36 bit word? A kludge. What does one do after the 36
>> bit address pointer? A worse kludge.
>
> I kind of suspected that was the case. Did anyone make a large 48 bit
> machine?
>
If you mean physically large, then yes. However on the 1301, addresses range only from 0 to 3999 (decimal).
Probably not what you meant really.
FYI, for the Amiga developers around here....
-------- Original Message --------
Subject: [Mandrakeot] Hey Gene - Amiga stuff
Date: Mon, 21 Dec 2009 21:54:21 -0500
From: Ric Moore
Reply-To: mandrakeot at mdw1982.com
To: mandrakeot at mdw1982.comhttp://feeds.arstechnica.com/~r/arstechnica/open-source/~3/KX0p_xQ7x7g/know…
Thought you'd get a kick outa this one. Ric
--
--- Dave Woyciesjes
--- ICQ# 905818
--- AIM - woyciesjes
--- CompTIA A+ Certified IT Tech - http://certification.comptia.org/
--- HDI Certified Support Center Analyst - http://www.ThinkHDI.com/
"From there to here,
From here to there,
Funny things
are everywhere."
--- Dr. Seuss
Hi,
Where are you located?
Can you use DDS (DAT) media?
I'm one of the "too busy" people, but perhaps I can get some time in between now and the
New Year.
On Dec 17, 2009, at 9:45 PM, g-wright at att.net wrote:
> I'm back to try this again. I need a boot tape for a HP 3000
> Micro GX machine. Does anyone have a working machine
> or a tape. I can use almost any media. I had 2 list members
> say they would help but they seem to be too busy and its
> been 6 months. I would really like to get this going.
>
> Thanks, Jerry
> g-wright at att.net
>
under
http://bitsavers.org/pdf/intel/MDS4
thanks to Bob R. for the loan of the originals
still looking for a couple of other multibus hardware manuals
isbc286/10, 386, 486S, 214, 215, 221 disk, 550,552 ethernet
nj
On 12/14/09, Alexandre Souza - Listas <pu1bzz.listas at gmail.com> wrote:
> Tony Duell wrote:
>> I suspect such players are too expenice _new_ for me even to consider
>> buying, and contain suffieicently complex custom ICs that it's a bad idea
>> to buy one for which manufacuters spares are no longer available.
>
> Want something hackable? Look for an AP660 from Apex. No service manual
> but full listing of the ROM :oD
I have one of those. Unlike most cheap-o consumer devices, there _is_
detailed internals data available - detailed enough to retool the
firmware.
It's not full circuit diagrams and datasheets, but from the software
side of things, much, much better than most devices.
It also has a bog-standard IDE DVD transport, unlike less expensive
devices. That's the model I was contemplating mounting the IDE-CF rig
on for the Click! experiment (since I already have some
3.5"-drive-bay-PCMCIA adapter frames on hand).
My main AP660 is on the fritz right now, but it's probably PSU issues.
Fortunately, I have a parts unit I can use to verify that everything
else is good with. I've had one since it was new and been very happy
with it.
-ethan
>
> From: Ben <bfranchuk at jetnet.ab.ca>
>
>> Because the Burroughs B5500 and B6700 computers used a word
>> containing 48 bits of data, but also extra bits that described the
>> type of the data which played an important role in programming the
>> machine, I would consider that series sufficiently out-of-the-
>> ordinary to attempt to discuss here;
This also included the Burroughs/Unisys A-series systems that were made
into the early 90s.
The A-series systems used a 52-bit, tagged word. 1 bit of parity, 3
bits of tag and 48 bits of data.
I don't recall how the addressing worked and Al has my papers on the
architecture, so I can't look it up ...
alan
On 12/9/09, Zane H. Healy <healyzh at aracnet.com> wrote:
> At 9:55 PM -0800 12/8/09, Chuck Guzis wrote:
>>On 8 Dec 2009 at 21:19, Zane H. Healy wrote:
>>
>>> Okay, this is the first time I've ever had to worry about this. When
>>> is it to cold to run a computer? It's 35F out in the garage, and it
>>> is supposed to get a lot colder tonight. I just shut the dehumidifier
>>> down (to cold to run it) and setup a heater near the computers (and
>>> other stuff I don't want to freeze).
>>
>>It seems to me that Ethan would be the perfect one to answer this.
>>35F is probably a heat wave at the South Pole.
>
> Except I don't think they run their computers outdoors! :-)
But we do use outside air to cool them. It's free except for the
power to push it around. (Oh... and +35F is never seen at the Pole -
the record is +7.5F, and I've personally been around for +7.0F).
As for the extreme case, we've had computers malfunction when outside
access doors were left open and -80F air came in directly, bypassing
the blowers and the louvers. On a day-to-day basis, the room with the
14 racks that was AMANDA (it was shut down earlier this year after a
10+ year run) shed about 35-40kW of heat with indirect access to
outside air with some measure of automatic and manual thermal controls
(covering up open cable panels and stuffing blankets in hatches in
addition to thermostatic controls on air blowers). If we let the room
get over about +55F, the high-voltage supplies for the photomultipler
tubes would go into thermal shutdown (ultra-dry air at 650millibars
doesn't have much heat capacity). OTOH, and more to the point, if we
let the room get much colder than about +35F (say +25F or colder), a
specific rack of digital hardware that was adjacent to the floor vents
feeding cold air to the high voltage supplies would malfunction until
the temp came up to the high thirties to low forties.
In another location entirely, central Ohio, I used to rent the
basement of my mother's typing and typesetting shop. The building was
a late 19th C/early 20th C brick "shotgun" commercial space with a
former storm-cellar-type access to the basement. As such, cold air
poured from the modern back door, down the basement stairs, and into
the space I ran PDP-8s, PDP-11s and a VAX-11/730. One of my jobs at
the time was hacking PDP-11 assembler on an 11/23. The basement would
routinely get to +40F, and sometimes colder if the wind was from the
right direction (the water pipes had electric wraps). I couldn't
personally stand to work in that environment without a heater pointed
at me, but the computers ran fine. The lone device that had problems
was an LA-180 printer I used for listings. It worked down to about
+45F, but colder than that, I speculate that the rail lubricant got
too viscous, because it would blow carriage motor fuses until it
warmed up. I quickly learned not to print on cold nights.
I'd say that if you keep things at or above freezing, you are probably
perfectly fine. Magnetic media is a lot more sensitive than ICs in
terms of cold soaking. One thing to watch for is to not power up
cold-soaked electronics. The current inrush is likely to blow ICs
(the internal bonded wires between the die and the frame, mostly).
I've thawed machines that were left in unheated buildings over the
winter at McMurdo - ordinary temps around -45F or so. Specifically in
that case (ultra cold, powered off), there are known and published
"max rates of rise" of temps to minimize the risk of permanent damage
>from thermal expansion. A good rule of thumb is about 2-3 degrees per
hour. What I did with the cold-soaked computers was to throw them
into a lab freezer at -40F for a few hours, then into a lab
environmental chamber at -30F that I would tweak up about 5 degrees
every couple of hours. When the chamber was up to about +20F, I threw
the equipment in a lab refrigerator. The thaw process took two
workdays, but 100% of what I treated that way survived (no hard disk -
these were floppy-booting diskless PCs that ran from a Novell server).
If it gets really cold (+0F, say), I'd bring the disks in the house
and leave the CPUs powered off until the garage temps are back around
+32F. ICs can be stored down to -40 typically, but not operated at
those temps (and especially not put through a power-on cycle at those
temps).
So that's my experience and observations of cold and computers. Take
away from it what you will.
-ethan
I just got the monitor for free from craigs list. (and a lead on possible
other equipment) Does anyone have the specs for this monitor? Google
searches have been fruitless.