Subject: Re: NetBSD/pdp10 ?
To: Brian Chase <>
From: Julius Sridhar <>
List: port-vax
Date: 03/07/2002 12:47:19
On Wed, 6 Mar 2002, Brian Chase wrote:

> > > The machine only had 18 bit pointers. It is a little light in terms of
> > > real memory space -- only about a megabyte in a full Moby.
> > That's not entirely true. The KL10-E (Used in 2060/2065 IIRC, someone may
> > correct me) had extended mode addressing which gave you a virtual
> > address space of 30 bits (but I think only 23 bits were used).
> > It should be quite possible to memory-wise to get NetBSD to run on
> > such machine, but I think the amount of work to make it run would
> > not be negligable :-)
> I wouldn't really expect there to be any (or many) real PDP-10 systems
> that would run such a port port.  Given the 18-bit pointers, I can see
> that being an impass, and I don't know if any of the emulators out there
> specfically support the KL10-E.

If I had a PDP-10 (I'm working on it), I'd put NetBSD on it.  Of course,
most of the time, I'd probably be running TOPS-20, but NetBSD would be
there, nevertheless.

> My curiosity has mostly to do with wondering if it's even possible to
> support the PDP-10 processors (or a subset of them).  And it seems like
> it would be possible.  Then beyond that, is there any merit in doing the
> port?  Not so much to provide yet another OS for the PDP-10, but more of
> it being an excercise of the portability of NetBSD.  At least to
> something a bit more unusual than the run-of-the-mill 32 and 64-bit
> processors.  Someone pointed out the arm26 port, which may have already
> achieved this.

As soon as I can scrape together a good chunk of time to sit down and do
it properly, there will be support for 31-bit multi-tiered memory for the
ESA/370 port.

> It would be a lot of work, and there are probably are a lot more
> pressing things for us spend our time solving.  But maybe there will be
> some people here both curious and able to pull off a port.  There would
> be some worth in the bragging rights.  Sort of like Linux has with their
> IBM mainframe port.

There *will* be a NetBSD/ESA port, goddamnit!  8-)

Peace...  Sridhar