Path: utzoo!utgpu!news-server.csri.toronto.edu!cs.utexas.edu!usc!wuarchive!udel!rochester!pt.cs.cmu.edu!a.gp.cs.cmu.edu!koopman From: koopman@a.gp.cs.cmu.edu (Philip Koopman) Newsgroups: comp.arch Subject: Re: Harrix RTX bites the dust? Summary: that's essentially a true statement Message-ID: <11135@pt.cs.cmu.edu> Date: 17 Nov 90 01:43:10 GMT References: <13287@encore.Encore.COM> Organization: Carnegie-Mellon University, CS/RI Lines: 67 In article <13287@encore.Encore.COM>, jcallen@Encore.COM (Jerry Callen) writes: > Speaking of stack-oriented architectures, has anyone else noticed > that Harris has stopped work on a 32 bit version of the RTX-2000 > stack-based processor? There was a blurb to this effect in the > November 12th issue of Electronic Buyer's News, of all places. This is an understatement. To quote an official Harris policy statement: "Harris has decided to discontinue future investments in new RTX standard products and development tools...". A more comprehensive version of this statement was posted on comp.lang.forth. The reasoning was that they are de-emphasizing digital in order to concentrate on analog, power, and mixed signal products. So, they are severely curtailing work (one is tempted to say, somewhat incorrectly stopped work), on all 16-bit RTX systems, and have definitely stopped all 32-bit RTX work. RTX is by no means the only project to suffer this fate at Harris, but certainly the highest profile project to be cut back. > I think this is the processor Harris touted in ads with a big fish > hook, saying something like "Don't buy that line about what a RISC > can do for your embedded system." Note that Harris is using the > Moto 88K in its line of real-time computers. Yes, this is the processor (and they took some heat for those ads too...). 1) The RTX was, IMO, an excellent solution for moderate- to low- cost embedded controllers. We saw several instances where RISC system solutions were just too expensive or not capable of doing the job (because of predictability problems or high interrupt overhead, usually) in things such as disk drive controllers and LAN controllers. Harris made its decision based on cash flow and high-level management woes, not on the quality of RTX technology 2) The division of Harris that makes the Nighthawk is not the same division as Harris Semiconductor. They don't talk. They don't collaborate. It seems that they'd rather avoid getting involved with each other. Also, the Nighthawk is a "big" real time system, clearly out of the class of system the RTX 2000 was ever intended for, so the technology would have been an inappropriate match. The 32-bit RTX maybe, but that was never really far enough along to be considered for the Nighthawk. > I don't know much about the RTX-2000 other than it is stack-based > and its preferred language is Forth. Does anyone have more details > about either the chip or the cancellation? The RTX 2000 was a stack-based "Forth" machine. But, it also had a C compiler. Its strength was low system cost and high real time responsiveness. Its weakness was being different than all the rest of the world. It appears that since Harris won't give it a real chance, we may never find out whether it was really a better solution. If you want to know more about stack oriented architectures, I recommend my book "Stack Computers", P. Koopman, Ellis Horwood Ltd, 1989. You can get it through inter-library loan, so this is not a pitch to actually buy it. Also, there is a summary of stack-based machines in Jack Woehr's article "Forth Machines" in the November 1990 issue of Embedded Systems Programming (although this article is perhaps as much or more about the players than the actual technology). Phil Koopman koopman@greyhound.ece.cmu.edu Arpanet 2525A Wexford Run Rd. Wexford, PA 15090 *** this space for rent *** I _used_ to be the senior scientist in charge of architecture for the RTX group at Harris. But, the above is only me talking since I don't work for Harris anymore.