Article 1482 of alt.sys.pdp10: Newsgroups: alt.sys.pdp10,comp.os.vms Path: shellx.best.com!news1.best.com!news.texas.net!news.kei.com!newsfeed.internetmci.com!in2.uu.net!world!mv!mv.mv.com!morris From: morris@mv.mv.com (Skipper W. Morris) Subject: Re: 36-bits or none at all! Message-ID: Organization: MV Communications, Inc. Date: Tue, 26 Dec 1995 05:51:20 GMT References: X-Nntp-Posting-Host: mv.mv.com Lines: 52 Xref: shellx.best.com alt.sys.pdp10:1482 comp.os.vms:31598 RE: VAXELN on a VAX front end. It was used on at least one VAX. If my foggy memory can be relied on I believe it was the VAX 9000. >> I think the Pascal-only support was in part inheritted from a product known >> as MicroPower Pascal, a real-time development environment (I'm not sure, >> that may have been a name shared with a PDP-11 product). Not quite. MPP and VAXELN were designed for similar markets (one for the VAX market, one for the PDP-11). As much as I can remember the decisions to use Pascal were made independently for each product, but for much the same reasons. >It *was* a PDP-11 product. I never looked at it closely, and I don't know >exactly how it fit in with RT-11 and RSX, both of which were aimed at the >real-time space. As I recall, it was a *really* "lean and mean" OS kernel. >(RSX-11S was, too, but in those days the only *supported* way to write >programs that did real-time stuff was in assembler - none of the RSX compilers MPP never really did "fit" in the RT-11 and RSX in the same way RT-11, RSX and RSTS were all kin. MPP was really aimed at the small programmable controller market. You'd have a large machine running VMS, RSX or RT with a large number of Kxx-nn series boards hanging off the Unibus/Qbus. You'd write your own realtime app that would be down-line-loaded onto all the controllers hanging off the bus. Before this product existed a customer would have to write KMS-11 microcode to do the same sort of thing. Since all the boards that MPP ran on were PDP-11 based, it was an easy thing for MPP to also be supported to run in standalone fashion on any PDP similar to VAXELN. I also seem to remember that both VAXELN and MPP could even be burned in ROM on a processor. RSX-11S was nothing more then a stripped down version of RSX-11M designed to be memory resident and down-line-loadable. Primarily used by the RSX customer base where they'd do their development on a big RSX timesharing machine, and they use small diskless PDP-11's for their apps. Similar in many respects to the apps that MPP was aimed at, however the product line groups and engineering groups were so far apart in DEC they never talked to each other. >> The product manager for VAXeln only knew Pascal. VAXeln may have been in >> part a renaming of MicroPower Pascal when C and Ada support were planned. > >Nope - separate product. Yes they were separate products, however for a time both products were supported by the same engineering group in the Mill. (Until MPP was retired). /Skip Morris