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!

Building pdp7-unix

pdp7-unix requires Perl5 to build.

To compile it:

make pdp7

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

PDP-7 simulator V4.0-0 Current        git commit id: aff3346e
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-18> 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
@ ln dd ken .
@ ls
dd
system
sop.s
s1.s
s2.s
s3.s
s4.s
s5.s
s6.s
s7.s
s8.s
maksys.s
trysys.s
sys.rc
.
@ ls system
dd      
ttyin   
keyboard
pptin   
ttyout  
display 
pptout  
apr     
as      
bc      
cas     
cat     
check   
chmod   
chown   
chrm    
cp      
date    
db      
ds      
dskres  
dsksav  
dsw     
ed      
init    
ln      
ls      
lsd     
lsl     
nm      
od      
p       
pd      
mv      
password
roff    
rn      
rm      
sh      
stat    
tm      
@ 

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