Relay-Version: version B 2.10 5/3/83; site utzoo.UUCP Path: utzoo!mnetor!uunet!seismo!sundc!pitstop!sun!oliveb!amiga!cbmvax!grr From: grr@cbmvax.UUCP (George Robbins) Newsgroups: comp.sys.amiga Subject: Re: CBM and upgrade paths Message-ID: <2756@cbmvax.UUCP> Date: Fri, 13-Nov-87 12:40:58 EST Article-I.D.: cbmvax.2756 Posted: Fri Nov 13 12:40:58 1987 Date-Received: Sun, 15-Nov-87 10:34:18 EST References: <8711040542.AA29099@violet.berkeley.edu> Reply-To: grr@cbmvax.UUCP (George Robbins) Organization: Commodore Technology, West Chester, PA Lines: 90 In article <5885@jade.BERKELEY.EDU> mwm@eris.BERKELEY.EDU (Mike (My watch has windows) Meyer) writes: > > <(and it is confusing the issues > > You're right - what *I* want is the ability to connect to Zorro > backplanes. But others will (do, from the postings regarding hacks to > various SOTS boxes, whether they pass the bus or not) want to connect > a SOTS to a Zorro backplane. True, it won't work very well; it never > really did. But if CBM had an 86-pin connector on the A2000, it'd have > a *much* better chance of working than it does now. Mike, in case you didn't notice. The A2000 just happens to have an 86 pin connector in it. It's cleverly described as either the MMU connector or the coprocessor slot. It just happens (who me?) to have the same pinout as the 86 pin as the A1000 expansion connecter, but of course in true West Chester fashion, the sex has been changed, but this actually is a good thing, or at least the only reasonable solution. Now this connector can be used just like the A1000 expansion connector, IF, IF, and ONLY IF you *don't* have any Zorro expansion cards plugged in. If you do plug in cards, life is apt to become quite confusing and I don't even want to try to guess what will work and what won't. You might want to ask why this little coincidence came to be. First, it does give the technically sophisticated A1000 user a little bit of a temporary upgrade path, albeit messy and unsupported, but sooner or later he'll most likely find a victim for his A1000 peripherals and will want to get some of the new goodies for his A2000. Secondly, it assures that any A2000 coprocessor cards should be easily adaptable to work on an A500 or A1000. Again, *completely unsupported*, but if the hooks are there, the hackers of the world will come up with the adapters. Happy yet? Sure it would be nice if there was an 86-pin connector sticking out the left-hand side of the box, but it doesn't look like it could be done reliably, and many SOTS devices weren't any too reliable in the first place. The idea of daisy chaining backplanes or devices sounds nice, but this is a whiz-bang digital computer, not a f*****g freight train. I think the Amiga folk were being a little more optimistic than realistic on this. Now I think I may have been the person who set you off on this prolonged tirade in the first place, when you came up with a perhaps justifiably paranoid interpretation of a comment I made. It may not be obvious, but I don't have time to answer every question that comes up, especially if I can't come up with a quick, informative, helpful reply, but know I have to type in some complicated missive, taking great care to avoid stepping or toes here, or hurting someones feelings out there. Everytime I type "rn" there's over 100 messages marked as being something I think I should comment on, or at least think about. After all, they pay me for being a design engineer, not a PR flack or even a developer/customer support being. Now to try to make things clear, all the people here who have worked on the A500, A1000 and A2000 have taken considerable pains to maintain a high degree of hardware* and software compatibility, while trying to incorporate what we consider to be improvements and accommodating the tradeoffs and compromises associated with the new products. We do not expect a sudden nasty change intended to screw over and cut off the A1000 owners, and would strongly object to such a thing. However, it is not within our authority or lack thereof to offer you any guaranty or commitment as to what Commodore may do in the future. * note: the Zorro I/Zorro II change was not West Chester engineering idea or decision, although we did get a chance to review the overall A2000 concept. Further, please remember that this is engineering here, and we run in a time warp that is anywhere from a few days to a year ahead of even usenet grapevine time. It is perfectly obvious that as time goes on new features and products will inevitably make the system you bought a year or two ago obsolescent and then obsolete, despite whatever efforts we make to maintain compatibility and create upgrade opportunities. This doesn't mean that it will be less useful than when you bought it, just that there will be better things and the world will have moved on. There still isn't any real market for classic computers, I've seen a PDP-11/45 system, the premier minicomputer of its era, sold at a flea market for $250. Now to work back around to my original comment, if you prefer the A1000, fine. If you like newer and in some ways better toys and have been tempted by the A2000, there's a special deal on, and now's a good time to take advantage of it, since I don't see it continuing much longer, nor a better deal coming along in a hurry. In either case, there'll be something better out the next year, and the next year, and the year after that, but if you wait for technological change to slow down, you're in for a long wait... -- George Robbins - now working for, uucp: {ihnp4|rutgers|allegra}!cbmvax!grr but no way officially representing arpa: out to lunch... Commodore, Engineering Department fone: 215-431-9255 (only by moonlite)