User talk:Vaxorcist

From Computer History Wiki
Jump to: navigation, search

Duplicate links

The Wikipedia Manual of Style's guidance on 'Duplicate and repeat links' seems sound (good) to me: "Generally, a link should appear only once in an article, but it may be repeated if helpful for readers". Not that it is a real problem to have a repeated link in a page! Jnc (talk) 17:49, 22 May 2022 (CEST)

750 option manuals

Do you have documentation for the CI750/DR750? I looked, but was unable to find anything on them (even the 1986 'VAX Hardware Handbook Volume 1') I did find mention of the second DW750 (I forget where I saw it - probably in the KA750 TD). Jnc (talk) 19:12, 29 May 2022 (CEST)

I will add that, I promise! Vaxorcist (talk) 21:56, 29 May 2022 (CEST)
That was not a 'push' to add content, but a real query. :-) RH750 Massbus Adapter mentions them, but I was unable to find any DEC documentation that mentions them. (Oh, I see BitSavers has the CI750 FMPS.) Jnc (talk) 23:38, 29 May 2022 (CEST)

750 Revision Control document

I am curious; where did the VAX-11/750 & VAX-11/751 Revision Control document come from? (It is a very interesting document, by the way; thank you for putting it online.) It does not seem to be online anywhere else. Did you scan/OCR a physical document that you have? Or did some VMS or diagnostics release include it? Jnc (talk) 00:29, 31 May 2022 (CEST)

See new page: "DEC MDS" Vaxorcist (talk) 09:26, 31 May 2022 (CEST)
Thanks! I wonder why Web search engines don't know of them? They must have robots.txt files, or something. Alas, I didn't see any PDP-11 information there, though! :-) Jnc (talk) 13:45, 31 May 2022 (CEST)

CMI clarification

I think we need to be more careful the CMI material. It turns out that is only one large backplane in the 750, into which plug:

  • the KA750 cards (which have internal busses, such as the MBus and WBus, running between them)
  • /750 CMI option cards (RH750, etc)
  • memory array boards (in a separate section of the backplane, with different connectors from the other two types of boards)

The CMI appears on the CPU backplane, and goes to some slots/cards, but most of the 'main' slots (specifically, slots 1-6 and 10) are 'special'; i.e. they are customized to a particular board, which has to go in that slot - and that slot can't hold anything else. (An example is the MIC board's slot, 10; the CMI runs to it, but the internal memory bus to the memory array boards - which does not seem to have a formal name - also goes to this slot.) Similarly, according to the KA750 TD, pg. 15, the MBus and WBus both run to the DPM, MIC and FPA cards/slots; but the UBI card/slot has only the WBus, but not the MBus. The CMI runs to some cards/slots - MIC and UBI - but not others: not the DPM, nor the FPA.

So it would be wrong to describe the FPA as a 'CBI' card. It's not; it's part of the KA750, and plugs into the /750 backplane which carries the CMI to other slots, but that's all.

I think we shouldn't put much weight on whether boards plug into the 'main' slots (1-10) on the /750 backplane, because that section holds a mix of special-purpose slots, and 'CMI option' slots (7-9). Although cards that the CMI goes to (MIC, UBI, RDM, WCS) are in some sense 'CMI' cards... because they have dedicated, customized, slots, I would rather reserve the term 'CMI card' for the cards that can go in the CMI option slots: RH780, etc.

Does this make sense? Jnc (talk) 19:10, 2 June 2022 (CEST)

Yes, you are right! I read some manuals again caring how DEC named its components.
There is neither a "Memory Backplane" nor a "CMI Backplane", but only ONE "CPU Backplane" with 10 "Extended hex slots" for CPU cards including 3 "CMI option slots" (7, 8, and 9), and 9 "Hex slots" for memory boards. The 9-slot UNIBUS Backplane DD11 is a separate unit, of course.
So there is a CMI bus, and there are three CMI option slots in the CPU backplane, but there is no CMI backplane.
May I leave the corresponding corrections to you? Vaxorcist (talk) 13:18, 3 June 2022 (CEST)
Yes, I would be happy to do them; in fact, I have been thinking since last evening how best to arrange the overall 750 description. (And I uploaded that wonderful block diagram, File:VAX750block.jpg, which I believe should be central to most articles about the 750.) Let me go re-do the main 750 article (as the first step). Jnc (talk) 15:45, 3 June 2022 (CEST)
Wonderful diagram indeed - go ahead! Vaxorcist (talk) 18:31, 3 June 2022 (CEST)
OK, all done. In addition to trying to clean up the main /750 article, I also tried to rationally allocate content between it, and the KA750, MS750 and CMI pages. E.g. I left the 'CMI configuration' table in the CMI page, as it could logically go either there or the main /750 page, but leaving it in the CMI page meant the /750 page was shorter.
Thank you for putting up with my 'help' on the /750! :-) Jnc (talk) 23:50, 3 June 2022 (CEST)

Category: DEC Hardware

Category:DEC Hardware is for (as the header says) "ancillary mechanical hardware". So not boards of any kind. (Although there is a Category:DEC Boards, they mostly all go into separate categories Category:DEC Memories, Category:DEC Peripherals, etc - actually often sub-categories of those, such as Category:UNIBUS Memories.)

There are some pages in the Category:DEC Hardware (e.g. Three cycle data break) which aren't mechanical, and should probably be elsewhere - but the question is 'where?' We don't have a category DEC Electronics, or anything. Maybe time to add one, or something like that? Do you have any suggestions?

I see that MicroVAX I uses Template:InfoboxVAX-Data, which automagically adds any page that uses it to Category:DEC VAX systems, so that page does have a correct category already. (I think that is probably the best category for it. If you do a separate page for the processor board, that can/should go in Category:DEC VAX Processors - and probably in Category:QBUS Processors too. Actually, by analogy with Category:PDP-11 QBUS Processors, probably in Category:VAX QBUS Processors; I see we have several already, I will set that sub-category up, and move them into it.)

I am not wild about templates adding pages to categories; I feel that it is better to do it explicitly, where anyone working on the page can easily see exactly which categories it is in. I have left this template alone, though, as I am not up for changing all the pages that use that template to have an explicit category. Jnc (talk) 23:56, 14 June 2022 (CEST)

So, there's a good example of why having templates automagically add pages to categories is a bad idea! I went to set up Category:VAX QBUS Processors and move pages into it, and discovered that Template:InfoboxVAXCPU-Data was adding them to Category:DEC VAX Processors! @%$^$!! So I removed that 'feature', and now we can assign pages to categories as we see fit. Jnc (talk) 00:09, 15 June 2022 (CEST)

3BSD

Everyone seems to call it just plain '3BSD': that is certainly what the people who did it called it - see e.g. Kirk McKusick here: "an enhanced version of 3BSD for the use of the DARPA community". (You will find the same thing in Peter H. Salus' book, "A Quarter Century of Unix".) The original documentation doesn't seem to include a short name; see e.g. Setting up the Third Berkeley Software Tape. (If you do Web searches for "3.0BSD" and "3.0 BSD", almost all the hits are for BMW car parts.)

The 'BSD X.Y' form did not really arrive until 4.1BSD (see here: "Rather than continue shipping 4BSD, the tuned-up system ... was released as 4.1BSD in June, 1981"). So, I'm going to move it back to the '3BSD' name.

When I said/say "Follow naming system', I was referring to not using names of the form "DEC xxx". Although some pages are called "{organization} {thing}" (e.g. Interlan NI1010A/NI2010A Ethernet interface (which is actually slightly incorrect; Interlan called it the 'Ethernet Communications Controller'; I will have to fix that), in general I don't use 'DEC' to start page names unless either i) the rest is a common term that might be used by someone else (e.g. DEC Alpha), or ii) it is a natural part of the name (e.g. DEC standard power wire colour coding). (Yes, I know that making DEC pages special is itself inconsistent! But the page names would all be longer, if not: 'DEC PDP-10' instead of PDP-10.)

But in general I try and follow the rule 'use what the original contemporary documentation used' - mostly because that is easy to find out, and then one does not have to think about choosing something! There are some places which fail to do that (e.g. KL10 - although now that I look, that might be correct): KA11 CPU should be 'KA11 Processor' (because I started calling all the PDP-11 CPU pages 'xx11 CPU' - although DEC has a lack of consistency in their naming for them; e.g. they call the KD11-E CPU just "KD11-E"). But I am slowly fixing many of them. Jnc (talk) 13:07, 22 June 2022 (CEST)