norman@a.cs.okstate.edu (Norman Graham) (09/11/87)
According to Rand Miller's artical in the September issue of Macazine, the "Mac II is designed so this new chip [the 68030] will pop right in to replace the 68020." Now grant you, I'm not a hardware type (in fact, semantics of programming languages is my game) but it seems to me that with the double bus structure of the 68030 the pinouts would not match. Would any enlightend hardware person like to comment on this? Are the pinouts the same (implying that the "Harvard style parallel architecture" is not seen off chip)? Norman Graham (norman @ okstate)
lalonde@nicmad.UUCP (John Lalonde) (09/11/87)
>"Mac II is designed so this new chip [the 68030] will pop right in to >replace the 68020." > >of the 68030 the pinouts would not match. Would any enlightend hardware >person like to comment on this? Are the pinouts the same (implying that >the "Harvard style parallel architecture" is not seen off chip)? I am not an enlightened hardware person but I do have pinout info on the 68030 from Motorola. The 68020 and the 68030 do *NOT* have the same pinout. I believe that Apple tried to come up with an architecture which will allow 68030 based designs. It may be possible to design a 68030 daughterboard that plugs into a 68020 socket but that would take an enlightened hardware person to give an answer for that. :=} I don't think Apple has ever said, implied or hinted that the Mac II's 68020 could be directly replaced by a 68030. If they did they are misleading people. If you want a real 68030 based system that does not use some type of kludge daughterboard, you will have to wait for the next machine in the Mac II architecture family. -- John LaLonde Systems Engineering Group Nicolet Instrument Corporation uucp: {ihnp4,seismo,decvax,harvard}!uwvax!nicmad!lalonde
stergios@rocky.STANFORD.EDU (Stergios Marinopoul) (09/12/87)
In article <2549@okstate.UUCP> norman@a.cs.okstate.edu (Norman Graham) writes: >According to Rand Miller's artical in the September issue of Macazine, the >"Mac II is designed so this new chip [the 68030] will pop right in to >replace the 68020." > {edited} >Are the pinouts the same (implying that >the "Harvard style parallel architecture" is not seen off chip)? > >Norman Graham (norman @ okstate) I'll speculate on this a little even though I have not read the article. Even though the 020 has 32 address lines and the 000 has 24, you can still pop in the former in the latter with a little glue simulating the requests for lower or upper word on data transfers. You simply map the higher data lines on the first 16, and let the 020 run at half the bandwith on long data moves. ( for a complete description on the how to's see EDN Jan. 23, 86) Now this probably not the problem you are refering to, however I suspect similiar gluing can be acomplished to make the two (020 & 030) compatable. In any event, you propbably wont get the full performance increase available, but half is still pretty good. Stergios Marinopoulos S&M Engineering -- % UUCP: !decwrl!rocky.stanford.edu!stergios % % ARPA: f.flex@othello.stanford.edu % % USnail: Crothers Memorial #690, Stanford, CA. 94305 % % Pa Bell: (415) 326-9051 %
jww@sdcsvax.UCSD.EDU (Joel West) (09/12/87)
The pin-outs of a 68882 match the 68881, so, theoretically,
you can pop it out. But no, the 030 and 020 are not pin-compatible,
so I have no idea what they were talking about.
--
Joel West (c/o UCSD)
Palomar Software, Inc., P.O. Box 2635, Vista, CA 92083
{ucbvax,ihnp4}!sdcsvax!jww jww@sdcsvax.ucsd.edu
or ihnp4!crash!palomar!joel joel@palomar.cts.comstuart@ihlpf.ATT.COM (Stu Ericson) (09/14/87)
In article <2549@okstate.UUCP>, norman@a.cs.okstate.edu (Norman Graham) writes: > According to Rand Miller's artical in the September issue of Macazine, the > "Mac II is designed so this new chip [the 68030] will pop right in to > replace the 68020." well, that's probably stretching it - more Motorolla's good design [he's not a hardware man..] > person like to comment on this? Are the pinouts the same (implying that > the "Harvard style parallel architecture" is not seen off chip)? The difference in pin-outs comes from the fact that they put a subset of the 68851 PMMU into the '030. This means they need to have PMMU special pins and such. Because the Mac II has a spot for the PMMU, it should be easy to wire up a board to map the pins of the '030 into the '020 and PMMU socket. In fact, I've heard rumors that Apple people in their labs have done this with sample '030s with success. Stu -- Stuart Ericson USnail: AT&T Bell Laboratories USENET: ...!ihnp4!ihlpf!stuart IH 6M-313 voice: (312) 979-4152 Naperville-Wheaton Rd. Naperville, Il 60566
devoz@encore.UUCP (Joe Devincentis) (09/16/87)
[] Guys. It is simple. You want a 68030, you wait for the 68030 macII BOARD TO BE DESIGNED. This should be a simple plug in :-) to the NUBUS, theoretically giving you a multiple CPU (can you say parallel?) workstation. Yes you can plug the new 68030 into your macII, but it must be on it's own CARD. The macII should last quite a while.... devoz@encore "And I turned around to see that even my shadow had deserted me"
susser@parcvax.Xerox.COM (Josh Susser) (09/17/87)
[gulp] In article <1945@encore.UUCP> devoz@encore.UUCP (Joe Devincentis) writes: >Guys. It is simple. You want a 68030, you wait for the 68030 macII >BOARD TO BE DESIGNED. This should be a simple plug in :-) to the NUBUS, >theoretically giving you a multiple CPU (can you say parallel?) workstation. > >Yes you can plug the new 68030 into your macII, but it must be on it's own >CARD. When I got my MacII, the first thing I did was open it up and look inside. (I didn't have a monitor, so what else was I supposed to do?) Aside from the overall cleanness of the design, the thing that impressed me most was that the 68020 was socketed (at least it looks that way) and was right next to the PMMU socket. From what I remember hearing about the 68030, it should be possible to build a tiny board with a 68030 and some SSI and plug it directly into the sockets for the 68020 and 68851. Voila, a MacII that runs twice as fast! Okay you Mac cognoscenti, am I on the right track here, or am I completely confused? By the way, looks like the 68881 is socketed as well, and the 68882 (which is twice as fast) is plug compatible. Apple, I like the way you guys design machines. --Josh Susser Xerox Special Information Systems Susser.pasa@Xerox.com Get up. What you seek is not written on the floor.