Massbus - was: Re: VAX 11/750

[Noel Chiappa]

    > From: Chris Zach

    > technically the MASSBUS cable is just an extension of the Unibus

No.

For one thing, the MASSBUS has no lines for carrying memory addresses. So
there is no way to even build a box that 'translates' MASSBUS to UNIBUS; the
semantics ('the things you can say', basically) of the two busses are so very
different.

(The MASSBUS is actually two separate busses; a control bus, and a data bus.
The former has 5 lines for 'register address', but that's all. While the
control bus is asynchronous, the data bus is synchronous.)

	Noel