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> It would be interesting to know why they didn't go with Motorola's own VME bus. VME cards are huge, and IIRC not keyed. IIRC Nubus was not only smaller but
by gumby 3y ago
> It would be interesting to know why they didn't go with Motorola's own VME bus.
VME cards are huge, and IIRC not keyed. IIRC Nubus was not only smaller but faster. Also, thanks to Apple at least, there were a wider variety of nubus boards; though VME was quite extensively used, it was mostly in industrial cases.
ISTR the CADR cardcage was VME, or at least had VME-sized boards.
- lispm 3y agoBoth NuBUS and VME were large. Apple was choosing a smaller form factor for their NuBUS use. The NuBUS probably was generally cheaper and faster than the VME-Bus. They were also easy to use for the end user. The original large VME-Bus cards was problematic for end users: large, fragile, expensive, ...
- jecel 3y agoIt is funny to see VME boards considered "large" (though there were options to allow them to be huge). The name is "VersaModules European format" replacing the 370x230mm VersaBus boards with 233.35x160mm 6U for typical VME boards. Simple i/o could use 3U (100x160mm) boards. This reduction was possible because of denser chips, specially PALs. Very large boards (9U height and/or 340mm or more depth) were used later, as I mentioned above. But I consider them the exception. Apple wanted an ISA-like form factor so the cards became 101.6mm high and between 177.8 and 327mm deep. So a bit smaller, but not that much than more typical VME boards. The less squarish form factor does make routing signals to the connector a little more complicated.
- lispm 3y agoMy Symbolics XL1200 Lisp Machine had size 9U x 400 Eurocard boards, with 7 slots. It comes with one Ivory Main Board and one Ivory I/O Board.
- Suzuran 3y agoCADR is XBus (its own thing) and Unibus.
- gumby 3y agoah yes, Unibus!