run Unix V1
I am very interested in the MEM11
for this exact reason. I have a
PDP-11/20 that I'd love to do this
with. [Ethan Dicks]
You could also try Mini-Unix on your
11/20, which might support a wider
range of devices. [Jay Jaeger]
Very interesting. Does Guy's MEM11
provide what's needed for Mini Unix
without having to write special
drivers? [John S.]
Not sure what Mini-Unix requires
w.r.t. devices.
TTFN - Guy
I think Jay might know, but I copied and
pasted the following paragraphs from
some info I collected on Mini Unix:
"The normal configuration for MX
includes a PDP-11/10 CPU with 28K words
of memory and two RK05 disk cartridges
for secondary. The PDP-11/10 processor
is slower than the PDP-11/40 processor
and does not have the full instruction
set of the PDP-11/40 processor, thus
requiring the emulation of the missing
instructions. A typical C compilation
requires about twice the total time of
that required on the equivalent
PDP-11/40 configuration. However,
response to the editor commands is not
significantly longer than on a more
powerful CPU. The cost of a minimum
configuration:
PDP-11/10 CPU
28K words memory
2 RK05 disk drives
KL11 interface to control console
DL11E interface to dial-up line
60 cycle clock
is of the order of $20,000 at today's
prices (December 1976). This provides an
inexpensive tool for software
development in a UNIX time-sharing
environment for those configurations
which have insufficient hardware to
support a full Version 6 UNIX system."
"The MINI-UNIX system runs on any PDP-11
processor with 28K words of memory. The
PDP-11 computer is a 16-bit word
mini-computer with a UNIBUS for
interfacing DEC peripherals to the CPU.
The typical configuration consists of a
PDP-11/10 CPU with 28K words of memory,
a console terminal and an RK05
moving-head disk controller with two
removable disk cartridges for swapping
and file system storage. Each RK05 disk
pack has 2.5 Megabytes (8-bit byte) of
storage. However, the MX system also
supports the RF fixed-head disk (1
Megabyte) and the RP03 and RP04
moving-head disk controllers with 40M
bytes and 80M bytes, respectively. Other
peripherals supported include
line-printer, Dectape, magtape and
various asynchronous and synchronous
interface units.
The system is normally configured to be
12K words in size. This includes an
emulation package for interpreting the
10 extended instructions normally
performed by the EIS hardware available
as an option on some PDP-11 processors
and standard on the PDP-11/45 processor.
A minimum system has room for 6 or 7
system buffers. As new drivers are added
to the system, the number of system
buffers must be decreased if the system
size is maintained at 12K words. Thus it
is recommended that for some
applications it may be appropriate to
add the drivers for only a few
peripherals on any one version of the
system and thus maintain a few versions
of the system, one for each set of
drivers desired concurrently in the
system. This keeps the system size at
12K words in order to be able to support
all of the user software of Version 6 UNIX."
