Talk:Digital Equipment Corporation/Archive 1

Date links
Re my last change - Lee, someone (I forget who, sorry) recently had the excellent idea to link all time-specific stuff with the standard text "as of " - e.g., "as of 200x, The Screaming Rhinoceroses have released 3,452 albums". The "as of " pages themselves just redirect to the "year" entries, but this way at the end of each year someone can look at all the pages that link to that year's "as of" page. Then they can all be checked, and either amended or changed to "as of ". Makes sense and should work a treat. --AW

Expansion ideas
What about TECO? And let's have more about PDP-8 and PDP-11 computers!

Could a better distinction be drawn between Lycos and Altavista? IIRC, AV was the first *automated* search engine (the first to gather data using a spider) - ISTR that all Lycos' data used to be collected manually. Is my memory correct? --AW

Data General and DEC
Although I am a former DEC employee, I admit that I don't know much about the whole DG-DEC saga, I did a google search, and I found this web page:. Based on that, I think we might want to be careful about what we say about Data General's alleged use of a DEC computer design. Here is what the web page says about this subject (I cannot vouch for its accuracy, of course). soulpatch It is worth mentioning that it is widely (but somewhat incorrectly) accepted that the Data General Nova (see photo, Computers and Automation, Nov. 1968, page 48) grew out of the PDP-X, a 16-bit multi-register version of the PDP-8 designed by Edson DeCastro, Henry Burkhardt and Dick Soggee. (DeCastro was one of DEC's key design engineers; his name appears on many of the blueprints for machines from the PDP-5 up through the PDP-8/L).

A prototype PDP-X was built at DEC; this and a competing 16-bit design were apparently submitted to Harold McFarland at Carnegie-Mellon University for evaluation; McFarland (and perhaps Gordon Bell, who was at C-MU at the time) evaluated the competing designs and rejected both in favor of what we now know as the PDP-11. (I was at Carnegie-Mellon at the time, and McFarland gave a guest lecture in a class I attended telling part of this story.) Some speculate, incorrectly, that Bell rejected the Nova design because the competing proposal used the register-transfer notation he had introduced in "Bell and Newell, Computer Structures -- Readings and Examples". An alternate and equally unfounded story is that the reason DEC never produced a PDP-13 was because the number 13 had been assigned to what became the Nova.

In any case, when DeCastro, Burkhardt and Soggee founded Data General, Ken Olson at DEC was very angry, claiming for a long time that the Nova design was stolen. Gordon Bell and others concluded that the Nova design was sufficiently original that a lawsuit was unwarranted, but the feud between DeCastro and Olson lasted until after Ken Olson left DEC. It is more correct to say that the Nova is a reaction to the PDP-X than to say that it is based on the PDP-X. I am indebted to Jim Campbell, retired VP at Data General, for some of the details of this story.

Closure of Peurto Rico subsidiary
On a personal note, I want to express my appreciation for the generous severance packages we received when the Puerto Rico subsidiary was closed down in 1993. Dick Beldin


 * Your thanks is no doubt appreciated, but it should not be on the head article. --drj


 * The fact that they had a Puerto Rico subsidiary and it was closed down in 1993 should be. But at the moment it would seem like a very incongrous piece of history to record.

HP-Compaq merger and DEC
I have identified DEC as being part of Compaq rather than HP, because the Compaq-HP merger hasn't actually taken place yet. Once the two companies merge, then the article can be changed.


 * I edited the page to show they merged with HP before checking here. But the merger has taken place now, right?


 * Also, I commented on them being called DEC within the industry, despite their attempt to rebrand themselves as Digital. I note that the rest of the article calls them Digital, which I have no objection to, but I'm wonderering whether they should be refered to by the brand that everyone actually uses to refer to them (including everyone on this page) rather than the brand that they wished everyone used to refer to them.

corporate strategy of Digital
My interest in Digital is from the standpoint of Ken Olsen's vision as a business leader and community promoter. Every time the company needed to grow, he bult a new plant in a smaller community in Massachussets. Each was connected by a helicopter shuttle service. He perceived the benefits of small town life for his employees.[Compare this scenario with Microsoft's mindless grwoth into the "blob that ate Redmond"].


 * Is it true, as I once heard, that the helicopter service was instituted because Ken Olsen had a bladder problem and wanted to be sure that he was never caught in traffic? Just wondering... Dpbsmith 13:22, 26 Nov 2003 (UTC)

Can readers a) give me more details about what Massachusetts towns DEC had plants in, and does HP-Compaq still have those plants running? b) provide examples of similar public spirited growth strategies in other companies (not necesarily computer companies)?

Thanks jrodwell@rvcog.org

The first laptop mentioned on the wiki/Digital_Equipment_Corporation page, namely the "DEC One" was actually the "Data General One". I don't believe DEC used the name 'One' in the fashion that DG did, nor could it claim the title of having the first laptop.


 * Yes, that's right. I remember the Data General One. It was notable for having a highly reflective, mirror-like screen with barely legible dark-grey text on a light-grey background. Ahead of its time, but not in a good way! Dpbsmith 13:13, 26 Nov 2003 (UTC)

There are some funny things in the article. The DEC One being one of them. DEC made several PC machines, but none named DEC One. You hade the DECmate, Rainbow, Professional and the VAXmate, to mention the more known ones.

And VAX with VMS didn't introduce virtual memory. The PDP-11 OSes also have virtual memory, as does Tops-10 and Tops-20.

There is no mention of the DEC terminal products, which is a rather major piece of history. Most people still run terminal emulators that act like a VT100.

And DECnet had been developed since the mid-70s. EASYNET was getting close to 60.000 nodes when I was at DEC in the mid-80s. I think it was the largest private internet in the world at the time. Internet (with a capital I) was growing fast and probably passed EASYNET around that time however. But Internet was not a private internet.

And DEC was the second largest company until Sperry and Burroughs were merged and renamed Unisys. This was around 1986 or so.

And the PDP-11 was not the last PDP made. The PDP-16 was the last. And DEC didn't build all early machines based on a 18-bit architecture. The PDP-1, PDP-4, PDP-7, PDP-9 and PDP-15 was 18-bit machines. The PDP-3, PDP-6 and PDP-10 were 36-bit machines, while the PDP-5, PDP-8 and PDP-12 were 12-bit machines. Finally you had the PDP-11 which were a 16-bitter. (The PDP-16 could also be called a 16-bit machine I think). That leaves the PDP-2, PDP-13 and PDP-14. I don't remember for sure (the information is out there somewhere, written by MRC) but I think the PDP-2 was a 24-bitter. The PDP-13 was never even designed (DEC avoided that number?) and the PDP-14 was perhaps best described as a 1-bit machine.

--bqt@update.uu.se


 * You are right. Don't have time to work on this now, but I did snip out the "DEC One" reference as that is utterly bogus. I'm not quite so sure about your claim that the PDP-11 OS's used virtual memory, but then I was an RT-11 user.


 * It would be nice to have a numerical table of the PDP-s with a concise summary of their characteristics.


 * And more details on the failed personal computers--I'll probably get around to saying something about that. The saddest to me was the 300-series, PDP-11-based PC running an RSX derivative. I truly think Digital could have changed the course of history if they had dropped the price on those to make them affordable to college professors and bundled BBN's RS-1 with it. Digital had a real, real problem with the concept of any machine that sold for less than $10,000.


 * And certainly there could be some work on what Digital's contributions were. I agree that the VT100 belongs there (I still remember how sensuous it was to have a smooth scroll). Digital's command-line languages certainly influenced the microcomputer generation, as did the name-dot-extension filename convention. And so did David Ahl's book on BASIC computer games! Dpbsmith 12:35, 11 Apr 2004 (UTC)


 * The PDP-11 OSs did not use virtual memory. Certainly not RSX-11M. I don't believe that the architecture of the machine would support virtual memory.  RSX-11M used overlays.  As the PDP-11s were essentially 16 bit machines, it hardly seems likely that any of them had virtual memory.  --206.127.177.59 05:51, 11 Mar 2005 (UTC)

DEC and virtual memory
1. The PDP-10 (running TOPS-10) most certainly did use virtual memory in its later incarnations (by 1977).

2. None of the DEC operating systems for the PDP-11 used virtual memory. The PDP-11 *DID* use virtual addressing and contained optional hardware to transform 16 bit (+/-) virtual addresses into 18 or 22-bit physical addresses. Wikipedia currently conflates the two concepts, redirecting "Virtual address" to the "virtual memory" article. In fact, they're quite different concepts and someone should fix that.

Atlant 20:58, 11 Mar 2005 (UTC)

Dave Cutler's exit
I was disappointed to see that the &quot;interesting&quot; story of how DEC very stupidly fired David Cutler, who was then hired by Microsoft and transformed NT from a joke into a monster that helped slit their throat, is missing from the otherwise high-quality entry.


 * (Cough) Well, why don't you fix it then? Assuming you can tone down your point-of-view a bit. Although according to http://www.melbournelinux.com/nt_history.html "fired" does not sound correct at all. We already have an article on David Cutler, a one-sentence description with a link to that article would certainly be in place.


 * Me, I'm still searching for a quotable and appropriate description for the story that when Robert Palmer took over, one of his first acts was to build himself a large and luxurious office suite in the Marlboro offices. It would be nice to have figures for the actual square footage of Olsen's office and his. Dpbsmith 13:06, 30 Apr 2004 (UTC)


 * I don't know about square footage, but Palmer's construction of his Powdermill Palace was legendary within DEC at the time. Olsen's office on ML10-2 was entirely commensurate with the rest of Digital and K.O.'s position in the company; nice, but not ostentatious, and obviously functional; the place an engineer could work. And Ken was the one guy in the corporation who had a reserved parking spot; you could often see his blue Ford Pinto (and later, a brown Ford Escort) parked right outside of Building 10. Palmer, in the meantime, even when he was in the Mill, was building palaces. His floor in Building 1 was vast, and practically empty, with lots of couches and glass-enclosed offices and conference rooms and the like. And every day, you could find his white Porsche parked up in "visitors" parking near the Thompson Street entrance to ML-5.


 * Meanwhile, Ken used to brag about how the Mill was very inexpensive space, even after all the renovations that Digital had done through the years as they first acquired all of the Mill and later transformed it from mightily-ugly to a very nice bare-brick/bare-wood/big-windowed space. But for some reason, when Ken was booted out and Palmer took over, the Mill suddenly became far too expensive to be productively occupied. Palmer had his palace built up at the old H.H. Scott building on Powdermill Road, complete with a private entrance. And Digital began decamping from the Mill, its spiritual heart and soul, and source of its corporate logo. Soon after, Digital decamped from the computer business and its corporate life.


 * As if to tweak DEC, when Sun Microsystems built their huge campus up in Burlington, Massachusetts, they constructed a clock tower.


 * Atlant 20:58, 11 Mar 2005 (UTC)

Some notes on the PDP-11 entry:

I seem to recall the following languages being available on RT-11 from DEC: Basic, FORTRAN-IV, APL, MU-Basic (A Multi-user basic; RT-11 didn't support multiple users, the BASIC environment did - up to eight terminals, as I recall). There was also FOCAL (altho I never saw/used it) and MUMPS (never saw/used).


 * I used FOCAL on a PDP-12, but not a PDP-11 (thought it was available). I used MU-Basic. Dpbsmith 14:39, 23 May 2004 (UTC)

The entry completely misses one of the OS's for the PDP-11's: RSTS/E, which was commonly found in educational environments. Interesting side-note to RSTS/E -- the system programming language for RSTS/E system was BASIC-Plus. BASIC-Plus bore only a slight resemblance to Dartmouth BASIC -- BASIC-Plus was BASIC on steroids and then some. It was a very powerful language in it's day.

Other languages available on PDP-11's included Algol (never saw/used), Bliss-11 and MACRO-11. Bliss-11 (for PDP-11's) and Bliss-32 (for VAX/VMS) were interesting language developments. They came from Carnegie-Mellon U. and were "highly optimizing compilers." This was putting it mildly -- Bliss-32 was the language that most of VMS was written in. The PDP-11 OS's were mostly written in Macro-11. Bliss-32 did things that no other high level language could do for you in that it allowed you very explicit control over the bitwise representation of your data structures, the physical location/alignment of your data structures in memory and exactly what instructions your program would generate. Long before C compilers were allowing programmers to insert assembly statements in-line with C code, Bliss compilers allowed the programmer to say things like "I want to divide this number by two - and use a logical right shift instruction to do it."

Perhaps something else that should be added to this entry is the fact that the PDP-8 and PDP-11 series of computers were some of the first computers that were dedicated or "embedded" into their applications. Today, we think of an "embedded system" as being physically small and having no terminal interface for the user to access. Well, the PDP-8 and PDP-11, using modules and user-programmable cards (available and supported from DEC, called "Flip-Chips") allowed the customer to design read-only memory and logic to support the embedding of a PDP-8 or PDP-11 into their application without a terminal interface. The computer would immediately start, read the customer's application code from ROM and commence running the application. Ergo, being "embedded" -- just not small, that's all.


 * Yeah, someone should write about their applications, in particular in typesetting machines. And, of course, there was a PDP-11 physically hidden inside the main bay of the VAX-11/780, doing various mysterious but important things, and rarely seen except on occasions when one could have the VAX access the 8" floppy drive in the PDP-11. Dpbsmith 14:39, 23 May 2004 (UTC)

In this vein, around about 1982 or 1983 (memory fails me now), DEC put out a truly "embedded OS" for PDP-11's called "MicroPower Pascal." This was a true multi-tasking kernel that could use memory mapping on PDP-11's that supported it or a simple single-address space model on PDP-11's that didn't support mapping. Software for this environment was typically developed with a cross-compilation environment hosted either on PDP-11's running RT-11 or on VAX/VMS systems. The Pascal compiler was a derivant of the Oregon Software Systems'(?) Pascal compiler. The compiler had some limitations and faults, but the MPP kernel was outstanding in it's day. At the time, there was no other "embedded OS" like it from any other minicomputer vendor.

It should be noted that the early VAXen could run PDP-11 software in a hardware compatibility mode. ie, beside the VAX instruction decode in the VAX hardware, there was also decode logic for the common PDP-11 instruction set. This was true on the VAX-11/780, 750, 730, 8600 and 8650. The MicroVAX product, wherein DEC implemented the VAX instruction set on a microprocessor, required that DEC jettison the PDP-11 instruction set out of the hardware, along with several very "fat" and little-used instructions for decimal string handling and other esoteric instructions. For the migration of PDP-11 s/w to VAX/VMS, DEC sold a PDP-11 migration product called "RTEMS", or the "RT-11 Emulation & Migration System." It literally used the PDP-11 instruction set available on the VAX, coupled with a special IO-mapping library, to allow the user to boot a copy of RT-11 in their process and then load/run "well-behaved" RT-11 programs. For those VAXen that did not have hardware PDP-11 instructions, DEC supplied a software emulation of PDP-11 instructions. On the highest-end VAXen available at that time (the VAX 8800 series), this ran acceptably fast.


 * One of the things that I've never forgiven Digital for--and I'm afraid I didn't save the relevant documentation, so I can't prove it--was that I attended a number of sessions when the VAX was brand-new and Digital was selling the concept. VAX stood for, and was billed as, a virtual address XTENSION--of the PDP-11, as indicated by the name VAX-11/780. At the time, I am 99.9% sure that Digital and the official VAX architecture manual billed PDP-11 instruction execution, not as some form of "emulation," but as an integral part of "the" VAX architecture. My belief is that the document that supposedly defined the VAX architecture was altered to redefine the PDP-11 instructions as not being a required part of the architecture, so that it could be claimed that the MicroVAXen were full implementations of the VAX architecture. Let me be very clear: I'm not complaining that the MicroVAX II wasn't a good machine or that it wasn't an appropriate tradeoff by the time the machine was released. What I'm complaining about is that they changed the architecture definition for marketing reasons and pretended that they hadn't done it. If they'd had the honesty to say "OK, the MicroVAX II implements the VAX architecture with the exception of the PDP-11 instructions," I'd have had no quarrel. As I say, I let the relevant documents go down the memory hole so I could be dead wrong about it, although other Digital users--who also didn't have the original edition of the architecture documents to refer to--have memories that agree with mine. Dpbsmith 14:39, 23 May 2004 (UTC)

At the time of the introduction of the MicroVAX I, DEC followed MicroPower Pascal with a similar environment for the VAX, called "VaxELN". Languages supported were Macro-32 (ie, assembler), VAX Pascal and VAX Ada-83. VaxELN was not well received, largely because DEC's management didn't want to sell VAX hardware as an upgrade. For example, the MicroVAX I and MicroVAX II computers were Q-bus systems. There was no reason why you could not pull out your PDP-11 CPU board from a Q-bus system and slip in a MicroVAX II CPU card. That is, there was no technical reason why you could not do this - DEC's engineers had made certain that this would work. DEC's management decided that customers could not buy only the MicroVAX II CPU cards without cramming a complete system and VMS down the customer's throat. The flexibility in pricing and support available to the customer upgrading from the PDP-11 product line to the VAX vanished when DEC hired ex-IBM management types and installed them into the VAX management team. The net:net effect was that embedded/dedicated-application PDP-11 customers had no upgrade path for their needs within the DEC product family. This was one of the things that, IMO, eventually led to DEC's demise. When they forced their loyal (fanatic might be a better term) PDP-11 customer base to seek upgrade paths outside of DEC's products, DEC lost their most long-term and zealous customer base.

One of the things that needs to be said about DEC and their machines was their early support of networking. DEC was one of the first companies to support Ethernet interfaces across many/most of their product line, and DECnet software supported at least a minimal "least common denominator" of functionality across all implementations. Most all implementations of DECnet would allow a user to log a terminal session into a remote machine or transfer files between machines. The full-fledged versions of DECnet (ie, really only the VMS implementation) would allow remote command execution, remote printing, etc.


 * I administered DECnet running on three or four VAXes. It was sweet. Cleanly designed, easy to administer, it "just worked." DECnet on other platforms was a bad joke. Some of my worst memories were trying to use the PC implementation of DECnet that they supplied for... whatever they called their overpriced AT clone. Feature after feature was not implemented, or implemented differently from the way it was on the VAX, or broken, or unreliable, or just plain wrong. We eventually gave up on it. Dpbsmith 14:39, 23 May 2004 (UTC)

Where DEC went wrong with DECnet was in pouring a great deal of engineering resources into what they called "DECnet Phase V", which was an implementation of the OSI network implementation, with X.400, FTAM, etc, etc. All for naught, because at that time, the Unix workstation market and cisco Systems made TCP/IP the de-facto standard. DEC was very, very slow to respond to customer needs for TCP/IP implementations on their products. This, coupled with DEC's tardy introduction of OpenVMS and the Alpha architecture, meant that DEC's customer base was easily picked off by the various Unix workstation vendors.

DEC was perhaps THE company that did more to lay the groundwork for personal computing than any other. PC-DOS looked more like RT-11 than anything else at the time. If Ken Olsen had been more open-minded, DEC could have owned the personal computing market. Engineers had long thought of PDP-11's running RT-11 as "personal" computers in that they didn't have to share the computer with anyone else and RT-11 was very user-friendly, yet exceedingly powerful, with a good selection of software and languages. Sadly, when DEC finally caught a clue that they had all the components necessary to capitalize on the idea of a "personal computer", they responded with the DEC "Professional" line of computers, which were castrated PDP-11's. Only the Professional 380 had an acceptable leveádÓdáàáá åTå£


 * Digital had, I think, three chances to own the personal computing market. The first was when the Intersil chip came out--the PDP-8-on-a-chip. Compared to the PC world, they had 12 bits instead of 8--meaningless but a good marketing point; a relatively slick and mature OS (OS/8 versus CP/M); and a relatively large library of comparatively well-written software. Plus a well-established users' group and hundreds of happy academic and commercial customers who knew and liked PDP-8's. If they'd only marketed that, heavily, instead of relegating it to the bastardized word-processing what-was-it-200....


 * The second, was, of course, the Pro-300 and its offshoots, together with BB&N's RS/1 software. That was such a sweet combination for any scientist or engineer. RS/1 was far more appropriate than any spreadsheet. Easy to use, knew all about the major statistical techniques, had what at the time was a pioneering compound document capability--a RUNOFF-like word processor that could embed RS/1 graphs and equations in it, sort of a primitive version of MathCAD or Mathematica. But... Digital insisted on charging $10,000 for the box, and BB&N, used to $25,000 licenses, charged $2000 for RS/1. Scientists and professors tend to be cheapskates and wouldn't have paid that kind of money for a system no matter how good it was, not when PC's cost $3000 and 1-2-3 cost $500. Digital could and should have used that system to own the educational market...


 * The third would have been a personal VAX. Had Digital ever decided to make one. Dpbsmith 14:36, 23 May 2004 (UTC)

"This finessed EBCDIC": Adherence to the ASCII standard was a real DEC accomplishment. They could have tried a proprietary character set like EBCDIC, but by sticking with a standard, and seriously adhering to it, DEC allowed interoperability at a very basic level. Thus the sucess of other standards efforts, per the article. Ancheta Wis 01:53, 24 May 2004 (UTC)

Up above, someone mentions MicroPower Pascal for the PDP-11. The proper name of the company that owned the base compiler technology was Oregon Software, Inc. I was the principle author of Oregon Software's compiler technology, and was a consultant to the team that produced MicroPower Pascal. I have no idea whether or not Ken Olsen's bladder had anything to do with the company's starting its helicopter service, but I must say that as a kid spending a week a month hacking for the MicroPower Pascal team, I appreciated being able to fly the DEC Airforce helicopter from Logan to one of DEC's facilities, and a DEC van from there to the Mill. One of the MicroPower Pascal team commuted daily from Rhode Island to the Mill using the corporate helicopter service. In essence the service was available to anyone who could show a legitimate business reason for using it. Amazing. There was a reason people loved to work for DEC. Don Baccus 70.59.134.42 01:19, 17 December 2005 (UTC)

The Maynard Mill
Back in the early 70s DEC used to make great play of having started in an old wool mill (used to be a standing joke since the Stroud valleys around were at that time full of disused mills) - could a little more be added on the famous Maynard Mill.

Dairy Equipment corporation
An anon snipped this:


 * This acronym was once officially used by DEC itself[ 1 ], but discarded in favor of "Digital" in order to avoid a trademark dispute with the Dairy Equipment Company of Madison, Wisconsin).

with the edit comment:


 * 68.109.114.240 (Removed nonsense about Dairy Equipment Corp trademark issue. As a long time employee I know that never happened.)

The existence of the Dairy Equipment Company, and their use of the DEC initialism prior to Digital's use of it is verifiable.

So is Digital's one-official use of the DEC acronym, although I have had long term Digital employees deny this. (I don't have any explanation as to why Digital employees wouldn't know about Digital's former use of "DEC." My assumption is that for whatever reason Digital must have been very assertive about promoting the new name internally and downplaying any use of "DEC.")

I have old manuals with the DEC logo. (And,yes, it's DEC by itself, not as part of a product name such as DECtape or DECwriter or DECsystem).

IIRC it was Alan Kotok who told me about the dispute with Dairy Equipment Company, but since this was a long time ago and I'm not presently in touch with him and don't have any verifiable evidence of this I won't reinsert the reference to the Dairy Equipment company until and unless I can come up with something verifiable.

(There may not have been any formal dispute, since it is hard to see how the dairy equipment company could claim any possibility of confusion with a computer company. Perhaps they just asked Digital to stop and Digital agreed, or something like that).

I would appreciate it if 68.109.114.240 would identify their position within Digital and, if I'm mistaken or Alan Kotok was kidding me or something, indicate the correct reason for Digital's abandonment of the "DEC" acronym. Dpbsmith (talk) 16:39, 20 September 2005 (UTC)

The oldest manual I have is for the LA210, printed in 1980. This uses the Digital logo throughout the manual. The copyright page also shows that "DEC" (among a number of others, which is of interest in itself) is a copyright of Digital. Gadget850 18:58, 20 September 2005 (UTC)


 * One of these days I'll get around to posting a picture of one of my "DEC Laboratory Modules". These were the very first products that Digital ever manufactured; each one was one or two logic gates packaged in a very cool extruded aluminum case that could be stacked up in a rack and wired with banana-plug patch cords. They feature a very bold use of the "DEC" logo.


 * Atlant 14:06, 21 September 2005 (UTC)


 * Well, my apologies to all. I contacted Alan Kotok, he remembers nothing of the sort. So I don't know from whom I heard this. I still hope something will eventually surface, as the first time I ever heard of Dairy Equipment Corporation it was in the context of someone at Digital saying something like "the marketing people are all stirred up and want to get rid of the name DEC because it's the same name used by the Dairy Equipment Company." But I shouldn't have put it in Wikipedia without better evidence. Dpbsmith (talk) 22:40, 21 September 2005 (UTC)

DEC Printer Supplies
Hello, we sell supplies online. There is still a demand for DEC printer ribbons and cartridges so we added them to our site. However, we are having a hard time identifying the DEC printers from the Compaq or the Genicom ones. Is there anyway to find a list of the Digital-branded printers only? Michael