>"Douglas H. Quebbeman" wrote:
> > Jerome writes:
> > There is a hobby version of Ersatz-11 which can be downloaded
> > for free: http://www.dbit.com/pub/
> > You will want to download at least /e11/ and /putr/ followed by
> > those portions that you want to initially focus on.
> > The commercial version does cost $ US 2999 for DOS/W95/W98/NT.
> Well, considering what John's done for the emulator movement
> I can't call that predatory pricing. If the market is there,
> then so be it... BTW, I realize we have many consultants on
> this list who can justify that cost as a business expense.
Jerome Fine replies:
I totally agree - for any commercial application, the cost of a real
PDP-11, including maintenance or proper hardware backup, is
almost always more than $ US 2999. On top of that, the
performance of even a current low end Pentium III is about
10 times a PDP-11/93. So for most commercial applications,
Ersatz-11 is far superior.
> I also realize people of various means are on this list. I
> do confess to wishing I had more "leverage"; I hope that
> doesn't get taken as class jealousy.
NOPE! There are many things I would appreciate having.
I know the difference between what I need and what I want
and what I would enjoy. And just because I can afford
something does not mean I need it - in fact more often
than not, if I can afford something and it would be "nice"
to have it, being able to say "YES!" is most often 99%
of the reason why I don't need to bother.
> > In particular, I am allowed to use a raw SCSI hard disk drive by:
> > MOUNT DU0: SCSI5:
> > where "5" is the SCSI ID of the SCSI hard drive. This allows me to
> > use the same SCSI hard disk drive with both Ersatz-11 and on
> > a real PDP-11 system.
> Ken Harrenstein's KLH-10 has this ability, although I haven't
> used it yet.
I might need some additional tools in W98 to manage without
this aspect of the MOUNT command in Ersatz-11, but it
sure makes things much easier.
The other feature that John Wilson added is the ability under
Ersatz-11 to associate a separate controller with each command as:
MOUNT DUA0: SCSI4:
SET DUA CSR=172150
SET DUA VECTOR=154
MOUNT DUB0: SCSI5:
SET DUB CSR=160334
SET DUB VECTOR=134
even though the drives at SCSI ID=4 and SCSI ID=5 are on
the same 50 pin SCSI cable connected to the same host adapter
on the PC - so the above is not possible (yet) on a real PDP-11
under RT-11 with just one SCSI host adapter.
By the way, under RT-11, you can
COPY DUX.SYS EUX.SYS
but don't try to boot from EUX.SYS until 7 words with a RAD50
value of DU are changed to EU.
Under RT-11, this means that if I have TWO SCSI hard drives
of 2 GBytes each, I can set up TWO MSCP device drivers
DUX.SYS and EUX.SYS, each one having 64 active RT-11
partitions. Thus I can reference up to 2 GBytes on each hard
disk drive (or DOS/W95/W98 hard disk file) simultaneously.
Since the current price of a 40 GByte EIDE hard drive is only
about $ US 100 and not much more for an 80 GByte hard drive,
having a few 2 GByte files is not so unreasonable.
Sincerely yours,
Jerome Fine
--
If you attempted to send a reply and the original e-mail
address has been discontinued due a high volume of junk
e-mail, then the semi-permanent e-mail address can be
obtained by replacing the four characters preceding the
'at' with the four digits of the current year.
Received on Tue Apr 16 2002 - 20:27:31 BST