test-drb November 2007

test-drb@ccmp.vtda.org

229 participants
508 discussions

MIT provides MULTICS source and documentation

by blstuart＠bellsouth.net

> > >> But what machines could run the that today? > > > > > > Anything you port it to. The segmentation architecture would be hard to fake. And the idea of segments is so deeply ingrained, I doubt you'd want to try. However, the x86 does seem to have the necessary segmentation structure. Unfortunately, it's only got 32-bit addresses. Even in the 60s, the Multics machines had 36. > > That's an interesting question. I can't think of that many machines > > with a hardware ring architecture, and it's not something that can be > > easily faked with more traditional architectures. It would be a fairly > > invasive "port". > > It pains me to say it, but you could just throw CPU horsepower and > memory at the problem. Yes and no. In principle, the only thing you'd have to ensure is that you gave control to the supervisor on a ring crossing. So you could make all pages not in the current ring inaccessible. On a page fault, apply the ring brackets in software and change the page tables as a result. At the very least, you'd take a performance hit. Having said that, somewhere in the back of my head, I want to say that the x86 has at least part of the mechanism already. So a port to it would be less painful than to a lot of others, except of course, for the smaller address space. Of course, I could be totally off. I'm certainly no Multics expert, and my memory of the details of the x86 segmentation are rusty at best. BLS

17 years, 1 month

MIT provides MULTICS source and documentation

by blstuart＠bellsouth.net

From: Chris Kennedy <chris at mainecoon.com> > > Brian L. Stuart wrote: > > >>From multicians.org: > > Although there were 64 rings (an illusion created by software) on > > GE 645 Multics, there are 8 rings, supported in hardware, on the > > Honeywell 6180 in its various models. > > As opposed to what? Four on the X86? > > The original question remains, how many rings does Multics need? Just > because eight were provided by hardware doesn't mean they were all used. For the most part, they used 0-4. I don't think you'd actually need 5-7. BLS

17 years, 1 month

MIT provides MULTICS source and documentation

by blstuart＠bellsouth.net

From: Chris Kennedy <chris at mainecoon.com> > > Sean Conner wrote: > > > I can think of several thousand that have been made over the past decade, > > all made with the Intel x86 architecture. It even has the segments that > > Multics used. Seems like a perfect match to me. > > Hence my question regarding the number of rings used by Multics. Just > because there's multiple contexts doesn't mean that there's _enough_ of > them. >From multicians.org: Although there were 64 rings (an illusion created by software) on GE 645 Multics, there are 8 rings, supported in hardware, on the Honeywell 6180 in its various models. BLS

17 years, 1 month

Found a NCR system 3400 BoatAnchor

by laura＠gbsncr.com

I am looking for information on how to find some part numbers to my NCR 3400 machine. I need one master slave (3) cables that go to the NCR3400 and the controller box (possible pn: 5300008319) for the tape drive (initialization tape 5 ?? tape). Please let me know if you can help. Laura Ellingson Sales & Marketing Manager Guarantee Business Systems, Inc. 800-650-1457, X429 651-286-8429-Direct 651-688-6160-Fax <mailto:laura at gbsncr.com> laura at gbsncr.com <http://www.gbsncr.com/> www.gbsncr.com GBS is a Woman Owned Small Business & Service Disabled Veteran Owned. We are a POS, Storage, networking hardware solution provider - in the IT industry since 1986.

17 years, 1 month

Architecture vs Implementation

by aek＠bitsavers.org

> If a processor has 16 bit registers, 16 bit math and address > calculation, and a 16 bit address bus, but it's ALU is only 8 bit and > its internal data bus is 8 bits, it's an 8 bit processor. Right? wrong -- The 360/30 /40 and /50 are all considered members of the same 32 bit architecture, and have 8, 16 and 32 bit data paths, respectively. An 80386/SX is not considered a 16 bit processor because it has a 16 bit data bus. People are confusing architecture with implementation. Is a PDP-8/S a one bit processor because it implements arithmetic serially?

17 years, 1 month

Older Apple Macintosh books, manuals, Apple 2e card.

by trag＠io.com

> Date: Mon, 12 Nov 2007 09:30:42 -0700 > From: Richard <legalize at xmission.com> > Subject: Re: Older Apple Macintosh books, manuals, Apple 2e card. > In article <38603.209.163.133.242.1194883321.squirrel at webmail.io.com>, > "Jeff Walther" <trag at io.com> writes: > >> The IIe card has an actual IIe-in-a-chip on board. It plugs into an LC >> slot. The "LC-slot" originated on the Mac LC, but was instantiated on >> many Mac models after that. > > Is the "LC-slot" referring to the form factor or the bus interface? Primarily the bus interface. There may have been other Apple connectors which used the same physical connector but were wired differently. I am not aware of any, but Apple did this with other connectors. For example, the PDS connector in the IIci, IIsi and SE/30 are the same physically, but the IIci's is wired quite a bit differently, and even the IIsi and SE/30 have minor differences, though the latter doesn't stop cards from being cross-compatible. > Is this a NuBus slot? No. Apple was very fond of the Euro Mini-DIN connector in various pin numbers, but it is not the same as a NuBus slot. >> A IIe expansion card enthusiast has a very informative website up on the >> topic. > Is this the one you're thinking about? > > <http://www.vintagemacworld.com/> > Apple IIe Card for the Macintosh LC Frequently Asked Questions That's it. Anywhere that FAQ and I differ, I'm probably wrong. Same for me and Cameron's post which I saw after I wrote mine. Jeff Walther

17 years, 1 month

At risk of polluting the list with micros- IRIS Indigo adv. for free.

by compoobah＠valleyimplants.com

See http://forums.nekochan.net/viewtopic.php?f=4&t=16095 Looks like a R3000 model with XS-24Z, XZ, or Elan graphics Not mine, in Oregon.

17 years, 1 month

CRC question

by dkelvey＠hotmail.com

> From: cclist at sydex.com > > On 11 Nov 2007 at 10:37, dwight elvey wrote: > >> To my knowledge, I don't know if any of the assemblers had >> a CRC calculator built in. The final check number was most >> likely calculated after the assembly and just added to the code. >> If in the listing, this may have been a second pass through >> the assembler. > > MAC certainly didn't have one. I assume that the last 2 bytes of the > ROM were the zero-CRC-makers. The "quick and dirty way" to get a > zero sum is to compuate the CRC for the first n-2 bytes of the size n > ROM, then iterate through the 65536 possible 16-bit combinations of > the "corrector" stopping when a zero CRC is hit. It shouldn't take > long, particularly if you're using an emulator on a modern PC. > > You could also work out the reverse polynomial, but that sounds like > too much work for what probably will amount to a one-off deal. > > Cheers, > Chuck Hi Chuck As I recall, you just play the CRC forward with 0's in the two bytes. The value in the CRC is then just put into the place of the two bytes. It the will cancel to zero. I'd have to check that but that is what I recall. I recall it wasn't all that complicated. Remember, CRC circuits in controller chip do this for floppy disk without complicated circuits. It has been some time since I played with CRC's. I once had to write test to check CRC chips that used the Chinese Remainder Theorem to make data correction. I had to make sure that it corrected correctly by checking each part of the error correction. That was many years ago. Dwight _________________________________________________________________ Boo!?Scare away worms, viruses and so much more! Try Windows Live OneCare! http://onecare.live.com/standard/en-us/purchase/trial.aspx?s_cid=wl_hotmail…

17 years, 1 month

cctalk Digest, Vol 51, Issue 37

by compoobah＠valleyimplants.com

On Nov 11, 2007, at 11:21 PM, cctalk-request at classiccmp.org wrote: > What I meant to say is that the investor who get in turn the hobby > into a > business. Get in buy low, trade items around between other investors to > drive up the costs, sell out and find another pump and dump hobby. It > leaves > people thinking their stuff is worth money when the people with the > money > are long gone. Granted people will dig up those rarities and trade them > around so they do not get trashed, so there is a plus side to it > (things get > preserved). > There's another factor here - people like Will and Paul and Sellam (probably) don't cater to deep-pocket collectors as their primary customers. They cater to businesses who still use the machines in day-to-day operations and are happy to pay what's needed for a part so they can get it next-business-day. The other market is lawyers looking for prior art evidence. In both cases the bankroll is substantially bigger than almost any collector, so collectors get locked out through no nefarious intent of the dealers. Remember there's quite a lot of overhead in locating, buying, storing, organizing, and dealing that one part that one person will need every 5 years (or longer for the lawyers - maybe only once in 50 years, but they're willing to pay). Off of this there is a certain amount of hype-induced market pumping (lookit how much that old thing sold for! I'm gonna dump my beanie babies and invest in cawm-pew-tuhs (yes, more sophisticated certainly, but it's a fun image), but that is vapor wealth because those people don't have the support to deal to businesses and probably have no interest in doing professional lawyer supply so the investment is probably as good as shares in "Gobi Rainforest Woods Limited" > The only thing stopping me from fighting over the big boys for my > collectables is that nothing I collect would interest the big deep > pocket > collectors in the first place. Everything I like was made in the > thousands > or millions, outbid me today and I just wait for the next one, or find > it at > a garage sale for $1. I guess if I was older and used computers pre > 1980, I > might want some of the rarer systems that command money, but they just > don't > mean anything to me so I don't bother. I certainly wouldn't mind trying out a HP2100 or 3000, or an IBM mini/mainframe, but definitely same boat here - wussy micros only (unless you count the TAAC board which might be a mini). I'm a bit gunshy too, after the trouble it took to outfit my $25 VAX 4200 I'm hesitant to get into something that I don't know especially if it's pricy.

17 years, 1 month

Older Apple Macintosh books, manuals, Apple 2e card.

by trag＠io.com

> Date: Sun, 11 Nov 2007 21:41:34 -0800 > From: Scott Quinn <compoobah at valleyimplants.com> > Subject: Re: Older Apple Macintosh books, manuals, Apple 2e card. > To: cctalk at classiccmp.org > The Apple // cards (I think it was a //e) fit in the LC PDS (LC, LCII, > LCIII, not sure about the '040 LCs) and are a genuine Apple product > that was pretty much 100%. While most of the (usually schools) using > them would move their Apple // software to either 3.5" or hard disk, I > think that Apple made a Macintosh-compatible 5.25" floppy that would > read Apple // disks (I know they made an IBM 5.25"-compatible floppy > drive for Macintosh back in the late 1980s), but not many were sold. The IIe card has an actual IIe-in-a-chip on board. It plugs into an LC slot. The "LC-slot" originated on the Mac LC, but was instantiated on many Mac models after that. The rule to distinguish 68040 based machines with an LC slot is that 68040 machines which can boot into 24 bit addressing mode will support the IIe card and 68040 machines which cannot boot into 24 bit addressing mode (IOW, 32 bit only) cannot support the IIe card, even though it will plug into the LC slot. IIRC, the Quadra 605/LC605/P605 supports the IIe card and the Quadra 630 family (Q630, 631, 635, 636, 640, and LC and Performas with same numbers) does not. Most machines with an LC style expansion slot have no other expansion slots, so installation of a IIe card precludes adding an ethernet card and other expansions. The Q63x family has a comm slot and an LC slot, so one could have an ethernet card in the comm slot and a IIe board in the LC slot, if they supported the IIe, which they don't. Grrrrr. The IIe card has a connector on the back plane for a custom cable. The custom cable splits into a joystick connector and a floppy drive connector. So one can connect a IIe joystick to the IIe card and one can also connect a 5.25" floppy drive to the connector on the special cable. IIRC, there is a model(s) of 5.25" drive which will work and another (others?) which will not, but I don't rememember which is which. Still, one does not need a special 5.25" drive. The connector is for one of the external 5.25" drives which was supported on the original Mac IIe. The IIe card uses the host machine's keyboard, mouse, display, hard drive and built-in 3.5" floppy drive. A IIe expansion card enthusiast has a very informative website up on the topic. And I will be useless here and fail to have the URL. But the resource exists and covers the information above to a useful level of detail. Jeff Walther

17 years, 1 month

← Newer
1
...
30
31
32
33
34
35
36
...
51
Older →

Jump to page:

2024

2023

2022

2021

2020

2019

2018

2017

2016

2015

2014

2013

2012

2011

2010

2009

2008

2007

2006

2005

2004

2003

2002

2001

2000

1999

1998

1997

test-drb November 2007