2.11 BSD

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Well over on the HECNet mailing list, there has been quite a bit of excitement over the opencores project, that is a PDP11/70 system on a chip.

It’ll run on two FPGA eval boards, and can even boot up 2.11 BSD!

So I figured I’d get into some of the spirit, and see how far I could get with SIMH. Following the great instructions on vak.ru to get a 2.11 BSD tape installed into SIMH. I then spent some time trying to work out a working Ethernet configuration to at least be able to telnet into the VM… It seems the de driver under the PDP-11 suffers the same problem the VAX 11/780 had regarding something being flagged somewhere with errors. I didn’t ‘fix’ the simulator I took the shortcut, and fixed the driver to ignore all errors on the interface, and now I can telnet into it!

I’ve also modified the boot program, and init to auto-boot the kernel, and bring the system up into multi-user automatically.

So I just slapped together a zip file, and placed it on my sourceforge page here for downloading. I didn’t do an installer program this time, as I wanted to build some programs to make it more fun, but it seems that the PDP-11 is limited to 64k data/ 64k instructions for executables, so although I’ve compiled ircII, it will not link. I can verify that you can telnet into the VM (localhost 42323), and the pdp11 executable I’ve enclosed includes my SLiRP patches.

And.. it runs Zork!

I guess for the more adventitious, you could extract out the rest of the source, and apply the some 400+ patches to 2.11 BSD and have a current system. But if anyone knows how to build something like IRC on 2.11 BSD give me a shout.

Oh, and much to my surprise, this version includes zork, and it’s the same RT-11/LSI-11 binary that the VAX loaded up in some RT-11 syscall emulator.

13 thoughts on “2.11 BSD”

  1. what do you mean by '400+ patches'? like making a FreeBSD out of it? or that 2.11 BSD is supported with patches upto this day? the latter would be insanely cool. 😀

  3. wow. that's awesome. i recently got a Toshiba 300CDT laptop, which, for its age is an neat little machine, and i'm using it to try out ancient OSs (my current project is installing Rhapsody DR2). too bad that there's no i386 port of 2.11BSD.

  4. Well the 2.11 BSD stuff is really 4.3 backported… so really what you want is 4.3 BSD for the i386, which basically is 386 BSD….

    If you have lots of patience, and a billion floppies you can do it…..

  5. i don't know if this is piracy ot not (personally, i like to think of everything older than 10 years as abandonware), so feel free to yell at me if you think i should shut up, but..

    do you know where to get the 386BSD 1.0 CD-ROM? i'd prefer not having to pay for it (it was free back then, IIRC), but hey, it's worth a few dollars/euros if i can try it out. 🙂

  9. I searched everywhere for an IRC client that would actually compile on a PDP-11, but kept running into issues with the 64K Program/Data limitation of the architecture. The solution to the issue, of course, was to write my own client.

    I wrote a VERY minimal IRC client that runs on 2.11 BSD, based on SIC. I just got around to putting it onto Github.
    https://github.com/TangentDelta/PDP11IRC

    I have not yet implemented a command line argument parser, so the nick and server are hard-coded into the source at this time, and must be changed. Building it is as simple as running “cc irc.c -o irc”.

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