Able board on eBay

Noel Chiappa jnc at
Fri Mar 3 10:34:24 CST 2017

    > It's one part of a DMAX/16.

Oooh, good catch. I hadn't looked carefully at those faint images, I was just
looking at the brochure which had the separate images.

    > Not nearly as cool as an Enable :).

Yes; the ENABLE was pretty clever: it used an MUD backplane as an EUB
backplane, to hold the ENABLE and stock EUB memory cards; both the CPU _and_
DMA devices were on the incoming UNIBUS, and the ENABLE could tell whether a
read-write cycle was from the CPU, or a DMA device (if you look at the UNIBUS
spec, there's just enough to do that, even without being able to see NPG), and
routed it through the appropriate mapping, depending.


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