On 11/23/2019 2:10 PM, Noel Chiappa via cctalk wrote:
From: Rob Doyle
Your memory is correct. The RH11C was the buffered version of the
RH11
Umm, both the -AB and -B have FIFOs - confirmed from the prints. (I
have an M7294 if we want to confirm that the prints aren't confused.)
Now, maybe the -C has a _bigger_ FIFO (e.g. large enough to hold a
complete sector), I could definitely see that.
What's your source - I'd like to study/cite it? The only KS10 prints
I can find don't show the RP11-C?
Noel
http://www.bitsavers.org/pdf/dec/unibus/RH11-C_Engineering_Drawings.pdf
Well. I think you right about that. I compared the M7294 in the -AB
to the M7294-YA in the -C and they have the same size FIFOs.
Apologies. I think I was told that incorrectly.
However there is plenty of DEC documentation that mentions that the
RH11C has a "bus hog" mode for the KS10 disks so that the Unibus can do
back-to-back 18-bit transactions.
http://www.bitsavers.org/pdf/dec/pdp10/KS10/ksrefRev2.pdf
Rob.
