23 Nov
2010
23 Nov
'10
9:59 p.m.
On 11/23/2010 01:32 PM, Shoppa, Tim wrote:
t in an F11-based PDP-11 (11/23 or 11/24).
Off the top of my head... DEC also has 2901's in
the CI780, and the UDA50, and probably
A bunch of other peripherals/interconnects/host adapters I cannot recall at the moment.
Tim.
They were used in the RX02 as well.
2901:
There are 17 registers, 16 of which are addressable (RAM) and there is a
Q register that can be
used as accumulator. Both the Ram and the Q paths have shifters in them
and since the
alu can take data from ram and Q it makes sense that it can so 32bit
floating point with
modest external logic.
However the 2909/10/11 microprogram sequencers are not required. It's
possible to do
a fast (10mhz range) 4bit dedicated math processor or a lot of other things.
I still have maybe 16 of the 2901C (imox process) parts.
Allison