10 Apr
2012
10 Apr
'12
11:02 a.m.
I used to keep a PDT-150 at my parents house for late night games of ADVENTURE.
Small footprint, a little slow, but worked out well with a VT100.
On Tue, Apr 10, 2012 at 1:36 AM, Ethan Dicks <ethan.dicks at gmail.com> wrote:
On Mon, Apr 9, 2012 at 11:33 PM, Cameron Kaiser
<spectre at floodgap.com> wrote:
How much does a "bare" 11/23 do,
however? What do you use for mass storage?
(I did say I was totally ignorant of PDPs.)
It is not uncommon for the PDP-11/23 (or even PDP-11/03 for that
matter) to be paired with a DLV11J quad serial card. ?One serial point
is typically strapped as the console interface leaving three ports at
your disposal. ?One thing that's easy to do is set up a DOS or Linux
box as an emulated TU58 and boot RT-11 from that. ?Transfer rates are
usually 38400 bps, and emulated tape skips the long seek times. ?One
can also do this with a PDP-11/23+ board that happens to come with two
ports (and boot ROMs) on the CPU board.
In terms of traditional mass storage, an RLV11 was cheap back in the
day ($50 to $100 when I was seeing them in the mid-1980s) but it needs
a particular type of backplane and can only see, IIRC, 18-bits worth
of memory. ?The single-board RLV12 works anywhere there's room for a
quad card (i.e., nearly any one except for the dual-height mid-1970s
backplane for the LSI-11/2) and sees all 22 bits in a full-blown
machine. ?Either controller can address up to four RL01 (5MB) or RL02
(10MB) drives. ?More common was a floppy controller - an RXV11 that
could only talk to an RX01 drive (or an RX02 set to work as an RX01),
or an RXV21 that can talk to an RX02 in RX02 mode. ?Newer systems,
mid-1980s and on, tended towards an RQDX1 or RQDX2 or RQDX3. ?There
are a few differences between them, but they all talk to RX50 dual
5.25" drives and various models of ST506/ST412 hard drives ranging
from 5MB (a real ST506) to 154MB (a Maxtor XT2190 badged as an RD54).
In terms of physical size, the emulated TU58 is only a serial cable to
a laptop or desktop in the same room, the RQDXn interfaces to drives
that fit in a shoebox, then the RX01/RX02 are microwave oven-sized,
then the RL01/RL02 are as tall and wide and at least twice as deep as
a floppy drive. ?There are other options, but these were quite common
in their day and were typically larger still.
In terms of size, I'd say an emulated TU58 has the smallest footprint,
followed by an RXQD3 with a Teac FD55GFR strapped to be an RX33 (I
think that's supported on the RXDX3 - it is on the MicroVAX 2000).
-ethan