Path: utzoo!utgpu!news-server.csri.toronto.edu!rpi!usc!apple!amdcad!dgcad!dg-rtp!webo!cheshirecat!lewine From: lewine@cheshirecat.webo.dg.com (Donald Lewine) Newsgroups: comp.arch Subject: Re: Wanted DEC-10/20 stuff, and emulator Message-ID: <1991Apr19.185433.5818@webo.dg.com> Date: 19 Apr 91 18:54:33 GMT References: <9104171333.AA12267@cwns1.INS.CWRU.Edu> <1991Apr18.221109.29852@sbcs.sunysb.edu> Sender: usenet@webo.dg.com (Usenet Administration) Reply-To: uunet!dg!lewine Organization: Data General Corporation Lines: 36 In article <1991Apr18.221109.29852@sbcs.sunysb.edu>, jallen@eeserv1.ic.sunysb.edu (Joseph Allen) writes: |> Cool project! Maybe you can skip the extended address instructions (is that |> what you mean?), I don't think TOPS-20 used them (although I could be wrong |> about this). The byte instructions must be fun. (1) TOPS-20 *does* make use of the extended addressing stuff. I think that TOPS-10 does also. In any event, it is not that difficult to include. I don't know of any compilers that generate code that runs outside of section zero, but I have not looked in a long time. (2) The byte instructions are fairly easy. The biggest problem is dealing with 36-bits on a machine that has 32-bit longs. |> |> Once I heard a rumor that someone was going to put a DEC20 on a chip... anyone |> here about this? I have no other details. No. I designed a one chip PDP-10 as a test for some CAD tools and gate array technology. It was never built. I think I still have the design someplace. Took me a whole weekend! The real questions is: would anyone want one badly enough to to pay to get the gate array built? Also, DEC still has the rights to the software and I don't think they are willing to give it away. Anyway, I spent from about 1969-1980 building -10 software, hardware, and microcode. I would love to see a PDP-10 emulator, but not enough to do any work on it. I will be happy to answer questions on how the machine, or Tops-10 or Tops-20 worked. -------------------------------------------------------------------- Donald A. Lewine (508) 870-9008 Voice Data General Corporation (508) 366-0750 FAX 4400 Computer Drive. MS D112A Westboro, MA 01580 U.S.A. uucp: uunet!dg!lewine Internet: lewine@cheshirecat.webo.dg.com