pdp7-unix

About

pdp7-unix is a project to resurrect Unix on the PDP-7 from scans of the original assembly code done by Norman Wilson. The scans of PDP-7 Unix are in the Unix Archive as the files 0*.pdf.

Current Status

March 2016

We've written an assembler, a user-mode simulator and commented several source files. We now have these utilities running: as, cat, chmod, chown, chrm, cp, date, ln, ls, mv, stat. We have a working shell with some functionality missing. We have a working filesystem and we can now boot the kernel, launch init, login, get to a shell prompt and run the utilities.

Things to do: bring the system fully up on a PDP-7 system, fix any bugs and document everything. We have a real PDP-7 and SimH as target platforms.

October 2019

A second notebook with missing sources has been discovered and scanned. New files are being added to the scans directory as they are typed in!

January 2010

Unixv0 is running on a real PDP-7 at the Living Computer Museum. YouTube link

Building pdp7-unix

pdp7-unix requires Perl5 to build.

To compile it:

make

Running pdp7-unix

You will need simh 4.0 to run pdp7-unix. You can get the source code here. On 64-bit systems, you may need to set the C compiler's optimisation level to -O1.

Running from source

To run pdp-unix from the pdp7-unix source tree, do:

make run

Press ctl-e to break out the simulator into simh

Typical Output

A typical pdp7-unix session on simh looks like:

pdp7 unixv0.simh
k
PDP-7 simulator V4.0-0 Current        git commit id: b848cb12
CPU	idle disabled
	8KW, EAE
/Users/tom/projects/pdp7-unix/build/unixv0.simh-13> att rb image.fs
RB: buffering file in memory
/Users/tom/projects/pdp7-unix/build/unixv0.simh-17> att -U g2in 12345
Listening on port 12345
PDP-7 simulator configuration

CPU	idle disabled
CLK	60Hz, devno=00
PTR	devno=01
PTP	devno=02
TTI	devno=03
TTO	devno=04
LPT	disabled
DRM	disabled
RB	devno=71
DT	disabled
G2OUT	devno=05
G2IN	devno=43-44

login: ken
password: ken
@ ls
..
dd
maksys.s
s1.s
s2.s
s3.s
s4.s
s5.s
s6.s
s7.s
s8.s
sop.s
system
sys.rc
trysys.s
@ ls system
..
adm
apr
as
b
cas
cat
check
chmod
chown
chrm
cp
date
db
dd
display
ds
dskres
dsksav
dsw
dttt
ed
init
keyboard
link
list
ln
ls
moo
mv
nm
od
p
password
pptin
pptout
rm
rn
roff
salv
sh
stat
tm
ttyin
ttyout
ttt
un
@ 

Source Tree

The code in the original scans are (c) Novell who own the rights to the Unix source code. Everything that didn't come from the scanned files is GPLv3.

• /build is an area to build the kernel & filesystem and run them
• /man holds man pages
• /misc holds miscellaneous notes and information
• /scans holds the unmodified OCR versions of the scanned files
• /src/cmd holds the modified source code of the user-mode programs
• /src/sys holds the modified source code of the kernel
• /src/other holds PDP-7 source code which did not come from the scanned files
• /tools holds the source for the tools written to assist the project

License

pdp7-unix is under the GPLv3

Mailing List

We have a mailing list for those people actively involved in the restoration effort. Send e-mail to Warren Toomey (DoctorWkt) if you are keen to help out.

Travis Status