Running Unix System 7 or original BSDs (FreeBSD v.2.1, v4.2,...)

Hello,

Are there ways to run original Unix System 7 or original BSDs to build on hardware with modern architecture (x86, arm raspberry,...)?

Best regards
 
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PDP-11s are a type of computer (to be exact, I should say they are an architecture). They are not built to run a modern system. Look at the architecture, look at the word length, look at the address space: 16bit registers, 64K address space (can be doubled starting on the 11/45 by doing I/D split), FPU not built in (instead it is a peripheral that's accessed as IO), physical memory limitation to 22bits of address space. I've used various PDPs (mostly the 11/55 model, because it had good bus bandwidth with the Unibus and a reasonably fast CPU), and an LSI-11 (which by modern standards is dreadfully slow, but in the 80s was a good laboratory instrumentation control machine).

SystemV is not a computer. It is a flavor of Unix. Grammatically correct would be to say: It was a flavor of Unix, since I don't know whether it is sold any longer; that's all the complicated story of Novell, USL, SCO, and so on. To my knowledge, no pure SVR4 is sold today, although some commercial Unixes (AIX, HP-UX, ...) may still contain licensed source code from it.

The idea of running FreeBSD on System V is just wrong. It's like saying you want to drive a Ford on a Chevy. It makes no sense. And the idea of running a modern Unix-style OS on a PDP-11 like saying that you want to build a modern passenger car, but using the engine from a bicycle.

I'm sorry to be blunt, but your post seemed to be mostly confused word salad.

(Side remark: A friend of mine has a PDP-15 and a PDP-8 at home in the garage; the PDP-15 is fully functional, and last time I visited, the PDP-8 was down for maintenance. I don't know anyone who has a PDP-11 that still works, but most likely those exist.)
 
PDP-11s are a type of computer (to be exact, I should say they are an architecture). They are not built to run a modern system. Look at the architecture, look at the word length, look at the address space: 16bit registers, 64K address space (can be doubled starting on the 11/45 by doing I/D split), FPU not built in (instead it is a peripheral that's accessed as IO), physical memory limitation to 22bits of address space. I've used various PDPs (mostly the 11/55 model, because it had good bus bandwidth with the Unibus and a reasonably fast CPU), and an LSI-11 (which by modern standards is dreadfully slow, but in the 80s was a good laboratory instrumentation control machine).

SystemV is not a computer. It is a flavor of Unix. Grammatically correct would be to say: It was a flavor of Unix, since I don't know whether it is sold any longer; that's all the complicated story of Novell, USL, SCO, and so on. To my knowledge, no pure SVR4 is sold today, although some commercial Unixes (AIX, HP-UX, ...) may still contain licensed source code from it.

The idea of running FreeBSD on System V is just wrong. It's like saying you want to drive a Ford on a Chevy. It makes no sense. And the idea of running a modern Unix-style OS on a PDP-11 like saying that you want to build a modern passenger car, but using the engine from a bicycle.

I'm sorry to be blunt, but your post seemed to be mostly confused word salad.

(Side remark: A friend of mine has a PDP-15 and a PDP-8 at home in the garage; the PDP-15 is fully functional, and last time I visited, the PDP-8 was down for maintenance. I don't know anyone who has a PDP-11 that still works, but most likely those exist.)

Thank you !!
 
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Hi,

The source code for the AT&T releases for the PDP-11, and 32V (essentially V7 for the VAX), plus the original Berkeley sources (PDP-11 and VAX) and some derivatives are on github.

I don't recall that AT&T System III and derivatives were ever released publicly (they were protected by "trade secret"). But there appear to be some incomplete "dumps" on the net.

To run them, you will need either some ancient hardware or a simulator, like SimH.

The purpose of all this is almost always educational, and in that light, you may be interested in reading Lions’ Commentary on UNIX 6th Edition, with Source Code. The commentary and related source (you need the line numbers) are also available on-line in pdf format. You can also download Lions' specific V6 source from github.

I commend the Lions books to anyone wanting to understand the basics of how Unix works. Yes, they are old, very old. But they are elegant and instructive, rather than hardware-efficient or expansive. However, once you get the basics, the missing bits like virtual memory, networking, threads, video controllers, multi-CPUs, and the like, are all just adornments requiring a small incremental comprehension.

Cheers,
 
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