Re: A simple cpufreq(9)

[Rhialto <rhialto%falu.nl@localhost>]

On Thu 29 Sep 2011 at 08:50:24 -0400, Mouse wrote:
> > The cache and mmu are probably harder than the cpu :-)
> 
> I'm not sure the PDP-10 even _had_ cache; I'd have to do some digging
> on that score.  And I have no idea what it had for an MMU.  The only

I think the MMU differed depending on what operating system you used
(TOPS-20 or ITS), or rather the reverse: each OS needed its own
particular hardware. And the microcode differed too.

> non-power-of-two-word-size machine I've ever actually used, as far as I
> can recall, was a PDP-8.  I'm interested in NetBSD/pdp10 less for
> personal nostalgia value than for the code cleanup it would enforce.

It is quite nice actually to play with TOPS-20. It is surprisingly
advanced for its time. The Kermit command line interface is modeled
after its shell. ITS on the other hand is totally for hackers: its
user interface was basically the machine language debugger (DDT)
expanded with a few small utility commands. On the other hand, BSD's job
control must have been stolen from there, and probably the idea that a
command you run is executed in a separate process from the CLI.

Via http://panda.com/tops-20/ one can find an emulator and disk image to
get started. I actually improved network support in the emulator
(klh10-2.0h); I sent patches to the author but the release schedule is a
bit.... slow.

> SIMH has PDP-10 support; that would probably be a useful resource for
> anyone taking on a PDP-10 in an FPGA.

See http://neil.franklin.ch/Projects/PDP-10/ . Unfinished,
unfortunately.

> /~\ The ASCII                           Mouse
-Olaf.
-- 
___ Olaf 'Rhialto' Seibert  -- There's no point being grown-up if you 
\X/ rhialto/at/xs4all.nl    -- can't be childish sometimes. -The 4th Doctor