16 May
2012
16 May
'12
10:53 p.m.
On 5/16/2012 11:28 AM, Ethan Dicks wrote:
On Wed, May 16, 2012 at 1:37 PM, Eric Smith<eric at
brouhaha.com> wrote:
I think Glen Slick may have written that. I have one as well, purchased
before the above was discovered; it seemed too good to be true -- a
faster-than-11/93 CPU (w/4mb onboard) for ~$100 on eBay. And it mostly
was, alas.
The slim documentation Glen managed to find describes it as being "J-11
compatible," I'm not sure how one could claim that given that it doesn't
support the FP instruction set at all. Supposedly there's an add-on
board that adds that support, but I imagine those are in short supply.
Rod Smallwood wrote:
I didn't
recognize the QED993, so I googled it. Found this comment on
the v-c forum...
"The QED 993 is a Xlinix FPGA emulation of a PDP-11. It does not
appear to be fully compatible with a J-11 processor. For example, it
does not appear to have any FP11 instruction support, which is assumed
to be present in a J-11. I haven't been able to get RSTS/E 10.1 or
2.11BSD to run on one I have so for me it is not as interesting as I
had hoped." QED993 $175.00
Those are nice, but a lot
of us hobbyists are more interested in running
real DEC gear than in replacing a DEC CPU with an aftermarket CPU.
I would personally consider a PDP-11 implementation that could not run
2BSD to be seriously broken for my uses (yes I know about 2.9BSD vs
2.11BSD and Split I&D, etc - that's just about picking the correct
PDP-11 type). I surely don't need an uber-fast PDP-11 to run RT-11.
I got along fine with an 11/23 system for professional software dev
for years - as long as the compiles take a handful of minutes or less,
it's fast enough.
Agreed. I haven't yet put the QED to good use (not quite sure what that
would be at the moment -- anyone have suggestions for a good -11 OS (+
fun software) to run that doesn't use FP instructions (at all?). I've
been thinking of recompiling all of 2.11BSD with FP emulation but that's
a lot of work. Even the bootloader appears to use them.
- Josh
I don't have anything faster/newer than an 11/53, but for what I do,
it's enough. Mostly, I run RT-11 and a little 2BSD.
-ethan