>I have an unproven hypothesis that it might be unnecessary to
>'slow-down' NCR 53C94 clock rate when PMAZ-A is attached with
>slowly-clocked (12.5MHz) TURBOchannel option slots found in 3MIN or
>MAXINE.  A crude try with my MAXINE shows PMAZ-A still works at 25MHz
>clock rate, but I'm not sure it's globally true.

I haven't seen them, but I understand that the DEC drivers (both OSF/1
and Ultrix) set a slow 53c94 clock on half-speed TC busses.  The
Mach/SPrite code in 4.4BSD/pmax did so, too I think we should
understand why they did that, and be sure it's safe not to, before
changing.

I'm guessing, but could it be poissble for 2 or 3fast-clocked 53c94
PMAZ-As to overrun a 12.5MHz TC bus (or the host memory system)
causing DMA overrun and data loss?

So even if it works in practice, I'd be reluctant to commit this
unless it's sysctlable and defaults to off. Make sense?