[A lot of old-school tech chatter today!] Discussion of Multibus vs S-100 bus Joe apparently missed both Jeff's message about retrobrew computers, and my message on auction-site prices for S-100 boards. On price S-100 boards will be cheaper than Multibus (except collectables). I imagine he's caught up now. And a S-100 board of 5 X 10 inches is an awful lot of space. Multibus is about 6 X 12: whadda gonna do with either size? It's a lot of chips, especially modern chips. Jonathan makes the point: do something with something, then see where you go next. You don't have to start with your destination design, in fact it's advisable to start simpler and make your mistakes early. I'm relatively active in vintage Multibus. Certainly enough to agree with Jonathan Chapman's assessment of Multibus. It's a little more complicated than S-100 and IEEE-696. It can get a lot MORE complicated because these were used in complex industrial settings and industrial products (as were some S-100 systems). As David Guesswein suggests, there's not widespread vintage interests in Multibus, as those who worked on Multibus have aged-out of the vintage computing discussion. Also Multibus was an industrial product, whereas S-100 was both industrial and popular-computing in its lifetime. Essentially S-100 was the cheaper alternative to Multibus. Today there's a somewhat private Google group who have revived Intel-based Multibus development systems. https://groups.google.com/g/intel-devsys Otherwise a Web search may find various Multibus pages and sites with information (including mine). I'm not aware of all that many, but i don't engage much with many online discussion groups. If you find more activity online about Multibus, let me know! So discussion about Multibus that I'm aware of, quickly becomes discussions with engineers of decades of experience in programming or hardware design, about fairly busy systems that performed control or ran 20th century operating systems. I get intimidated, and I know some stuff. But the early bussed stuff - Multibus or S-100 bus or say STDbus - is approachable for the technically minded. Jon Chapman has revived the old OSI bussed systems and one 8080 multibus board. There's SWTPC, the SS-50 bus, with some revived new boards by corshamtech.com, that's a 6800 6809 classic bus. Busses get more obscure from there. There's many points of entry, for people who want to design up something at the vintage processor-chip level. and for each kind of "entry", there's of course people who have been there and know what's went on. But some of these are pretty complicated and busy, with lots of legacy stuff that can be intimidating or simply not of interest. Others are simpler: the single-board stuff was intended to be simpler and introductory. As I and others said: Joe, where you start may not be where you end up. There's good reason to make a few simpler things first, then more complicated things later. from the experience of doing so, you'll know what to look for and what's of interest to you in the next step. Put another way: I've had lots of people contact me (I have some reputation in the S-100 world) about their "ultimate S-100 system" who never got there. One reason may be, they didn't get enough prior experience on simpler systems or projects, and so were not able to "get traction" on critical S-100 concepts or complexities or about CP/M (the predominant OS for S-100). So they gave up. Regards, Herb Johnson -- Herbert R. Johnson, New Jersey in the USA http://www.retrotechnology.com OR .net preserve, recover, restore 1970's computing email: hjohnson AT retrotechnology DOT com or try later herbjohnson AT comcast DOT net