On 08/06/2019 03:42 AM, Dave Wade via cctalk wrote:
-----Original Message-----
From: cctalk <cctalk-boun...@classiccmp.org> On Behalf Of Grant Taylor via
cctalk
Sent: 06 August 2019 04:25
To: cctalk@classiccmp.org
Subject: Re: Alphaservers for free in Athabasca, Alberta
On 8/5/19 8:40 PM, ben via cctalk wrote:
Now why could it not be a nice little PDP 11.
I thought that it could be if it was running emulation software.
Or was that more that the VAX-11 could emulate a PDP-11 up to a specific
version & hardware combination? (Read: Did this functionality not get carried
forward to the Alphas?)
I think it went from the VAX fairly early in the model range. I don't believe
that any of the MicroVax machines implemented this.
The VAX Architecture manual
The VAX 11/780 definitely had PDP-11 emulation, apparently
in the microcode. I'm kind of guessing the 750 and 730 also
had this. As far as I know, no later machines had hardware
(microcode) emulation, and did it all by software. It
didn't take very long for DEC to recompile all the VMS
utilities into native VAX executables. I think we started
with VMS 3.x and very quickly updated to a 4.1 VMS version.
I was not aware of any PDP-11 code in them, but I did not
look very closely.
Jon
