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Comment by Pet_Ant | Hacker News Reader

How long till someone ports NetBSD to it now that it’s more viable?

There was work in the past: http://www.jp.netbsd.org/ports/pdp10/

The problem is that the PDP-10 is really unsuited to running C. It doesn't use 8-bit bytes and doesn't have a native "byte" datatype, just words and halfwords. There are byte instructions, but you have to construct a "byte pointer" to use them, which is a control word describing bytes of arbitrary size. The PDP-10 also has no single dedicated stack pointer, any AC except for the program counter can be used as a stack pointer, to its own independent stack if you want.

No dedicated stack pointer isn't much of a problem. Stack growing up might be.

Isn't stack direction an ABI convention rather than language or processor limit? I mean if you are trying to run existing PDP-10 binaries (I don't know of any that are publicly available), sure. But just to get to the point that you are running bash and serving and HTML Hello World from Apache, it shouldn't be an issue.

> 8-bit bytes

Doesn't the C standard just specify the minimum range of datatypes, and the max? Don't know if you can tell the size of actual bit without triggering UBI. (obviously not a C programmer)

The standard specifies that you must have an independently addressable unit of storage that corresponds to the basic character set. The PDP-10 does not have this.

Interesting. Found this story:

https://stackoverflow.com/a/8061758/254477

So, it has been ported to some weird platforms.

Oh, there is/was a C compiler for the -10 (KCC), but it wouldn't support the modern dialects that the *BSD kernels are written in. Just having the language isn't enough, you have to be able to support the build chain of a modern kernel.

Sadly it's just RPI inside

Does that matter? As long as system level instructions are emulated. I’m sure you could also whip up an FPGA if you wanted to.

http://pdp10.froghouse.org/

http://www.fpgaretrocomputing.org/pdp10x/

https://github.com/KS10FPGA/KS10FPGA

I haven’t checked, but I’m fairly certain it’s too big for Tiny Tapeout, so ASIC is out of the question unless you want to crowd source an older geometry.

TT supports multi block projects now, might be doable

It could be almost any $0.50 microprocessor from 2024 and still have more vastly horsepower than any PDP8 ever had.

The PDP10 was a 36-bit CPU with up to a few MIPS of compute power, however.

If you're going to make flip chips, let me know.

Oh I would love that so much, but missus already has issue with how I spent what little of my free time I have...

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