VMS Alpha emulator

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Dave Lightman

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May 26, 2021, 12:15:08 PMMay 26
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Anyone know of any good, updated open-source projects for AXP emulation that
they recommend? Has anyone successfully deployed it to AWS / GCP?

I messed with simh/vax a few years ago without much luck - I may revisit this
again for some old vax stuff... just curious if there are any new haps in the
AXP emulator space.

Lastly, anyone know of any decent VMS fpga projects of late?

dave

Arne Vajhøj

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May 26, 2021, 12:23:53 PMMay 26
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On 5/25/2021 11:19 PM, Dave Lightman wrote:
> Anyone know of any good, updated open-source projects for AXP emulation that
> they recommend? Has anyone successfully deployed it to AWS / GCP?
>
> I messed with simh/vax a few years ago without much luck - I may revisit this
> again for some old vax stuff... just curious if there are any new haps in the
> AXP emulator space.

There are several well known commercial Alpha emulators. Just write a
check and you can get everything you want.

Free is a bit more problematic.

I believe the most promising today is this:

https://github.com/lenticularis39/axpbox

Arne


Simon Clubley

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May 26, 2021, 2:25:54 PMMay 26
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On 2021-05-26, Arne Vajhøj <ar...@vajhoej.dk> wrote:
> On 5/25/2021 11:19 PM, Dave Lightman wrote:
>> Anyone know of any good, updated open-source projects for AXP emulation that
>> they recommend? Has anyone successfully deployed it to AWS / GCP?
>>
>> I messed with simh/vax a few years ago without much luck - I may revisit this
>> again for some old vax stuff... just curious if there are any new haps in the
>> AXP emulator space.

I've found simh to be very reliable for running VAX/VMS V7.3 and older
versions.

>
> There are several well known commercial Alpha emulators. Just write a
> check and you can get everything you want.
>
> Free is a bit more problematic.
>
> I believe the most promising today is this:
>
> https://github.com/lenticularis39/axpbox
>

There's also the limited configuration FreeAXP (which works just fine
for the things I use it for).

Simon.

--
Simon Clubley, clubley@remove_me.eisner.decus.org-Earth.UFP
Walking destinations on a map are further away than they appear.

Simon Clubley

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May 26, 2021, 2:29:20 PMMay 26
to
On 2021-05-25, Dave Lightman <Dave.L...@f143.n3.z21.fsxnet> wrote:
>
> Lastly, anyone know of any decent VMS fpga projects of late?
>

Your question is unclear, so for the benefit of anyone who might know:

Are you talking about doing FPGA work under VMS or are you talking
about FPGA implementations of the architectures that VMS runs on ?

Dave Lightman

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May 27, 2021, 10:15:14 PMMay 27
to
=?> There are several well known commercial Alpha emulators. Just write a
=?> check and you can get everything you want.
=?>

Yeah - certainly aware of those and don't have budget for those. No large
compute requirements.

=?> Free is a bit more problematic.
=?> I believe the most promising today is this:
=?> https://github.com/lenticularis39/axpbox
=?>
=?> Arne

Cool, I'll check out the project. Looks promising.

Thanks!

Dave Lightman

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May 27, 2021, 10:15:14 PMMay 27
to
SC> There's also the limited configuration FreeAXP (which works just fine
SC> for the things I use it for).
SC>
SC> Simon.
SC>

Yeah - I messed with FreeAXP a decade or so ago (it seems). IIRC it is WIN32
- I was hoping for something a little more akin to linux/bsd. Still a good
reminder. Thanks.

Dave Lightman

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May 27, 2021, 10:15:14 PMMay 27
to
SC> Your question is unclear, so for the benefit of anyone who might know:
SC>
SC> Are you talking about doing FPGA work under VMS or are you talking
SC> about FPGA implementations of the architectures that VMS runs on ?
SC>

Indeed.

The question was meant to ask if anyone knew of any recent FPGA projects that
emulate PDP/VAX. I'd be interested to run twenex / vms on one to compare it
to simh/charon.

I doubt I would mess with it, but if there were FPGA verilog/vhdl tools on
VMS, that would be an interesting bit of information as well.

Thanks!

dave

Chris Townley

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May 28, 2021, 9:50:00 AMMay 28
to
I think FreeAXP has improved. I use it extensively - you are limited in
the free version to 128Mb, a single SCSI bank and 1 NIC.

I run it under Windows running on a Ryzen 5 CPU with loads of memory,
and a dedicated NIC

Worth a try!

--
Chris Townley

Arne Vajhøj

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May 28, 2021, 10:18:04 AMMay 28
to
On 5/28/2021 9:49 AM, Chris Townley wrote:
> On 27/05/2021 14:29, Dave Lightman wrote:
>>   SC> There's also the limited configuration FreeAXP (which works just fine
>>
>> Yeah - I messed with FreeAXP a decade or so ago (it seems). IIRC it is
>> WIN32
>> - I was hoping for something a little more akin to linux/bsd. Still a
>> good
>> reminder.
>
> I think FreeAXP has improved. I use it extensively - you are limited in
> the free version to 128Mb, a single SCSI bank and 1 NIC.
>
> I run it under Windows running on a Ryzen 5 CPU with loads of memory,
> and a dedicated NIC
>
> Worth a try!

For some things 128 MB is OK.

But if one wants to mess with X, Java, Python, RDB, MySQL,
Apache, Tomcat, OSU, WASD etc. then it will likely be
too little.

Arne


John H. Reinhardt

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May 28, 2021, 2:39:08 PMMay 28
to
I don't know of anyone doing the VAX architecture in a FPGA.

One of the most popular (and best) PDP-11 implementation in FPGA is the PDP2011 project of Sytse van Slooten at https://pdp2011.sytse.net/wordpress/

There are a couple of others:

W11 - <https://wfjm.github.io/home/w11/>
POP11 - <http://labo.nshimizu.com/pop11.html>
Verilog PDP-11 - <http://www.heeltoe.com/download/pdp11/README.html>

Some haven't been active in a while. The PDP2011 project is active and Sytse is always working on improvements.

--
John H. Reinhardt

Dave Lightman

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May 28, 2021, 6:15:21 PMMay 28
to
JH> I don't know of anyone doing the VAX architecture in a FPGA.
JH>
JH> One of the most popular (and best) PDP-11 implementation in FPGA is the
JH> PDP2011 project of Sytse van Slooten at
JH> https://pdp2011.sytse.net/wordpress/
JH>

Thanks John! I'll check it out right now.

dave

gah4

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May 28, 2021, 7:50:10 PMMay 28
to
On Friday, May 28, 2021 at 6:50:00 AM UTC-7, Chris Townley wrote:
> On 27/05/2021 14:29, Dave Lightman wrote:

(snip)

> > Yeah - I messed with FreeAXP a decade or so ago (it seems). IIRC it is WIN32
> > - I was hoping for something a little more akin to linux/bsd. Still a good
> > reminder. Thanks.

> I think FreeAXP has improved. I use it extensively - you are limited in
> the free version to 128Mb, a single SCSI bank and 1 NIC.

Real 128M or virtual? Swapping from a RAM disk should be really fast compared
to 30 year old hardware. But if it is virtual, it is more of a problem.

Arne Vajhøj

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May 28, 2021, 7:57:47 PMMay 28
to
I believe it is emulated VMS RAM.

So:

|--128 MB VMS RAM--128 MB virtual memory on PC
processes on VMS--|
|--VMS disk--container file on PC

If the PC has SSD disk then it is a lot faster than the original RZ
disks. But I suspect some overhead.

Arne

Chris Townley

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May 28, 2021, 8:19:04 PMMay 28
to
The FreeAXP docs refers to virtual RAM, but as I have 32Gb RAM, I only
have very small swap file - only on an M2 SSD

--
Chris Townley

Zane H. Healy

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Jun 26, 2021, 4:29:07 PMJun 26
to
Dave Lightman <Dave.L...@f143.n3.z21.fsxnet> wrote:
> The question was meant to ask if anyone knew of any recent FPGA projects that
> emulate PDP/VAX. I'd be interested to run twenex / vms on one to compare it
> to simh/charon.
>
> I doubt I would mess with it, but if there were FPGA verilog/vhdl tools on
> VMS, that would be an interesting bit of information as well.

Here is the latest info I have, though it's very out of date. I have far
too many things going on and a lot of the website is out of date. It looks
like I last updated the FPGA section in 2017.

http://www.avanthar.com/healyzh/decemulation/pdp_fpga.html

Zane

Zane H. Healy

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Jun 26, 2021, 5:03:23 PMJun 26
to
John H. Reinhardt <johnhre...@thereinhardts.org> wrote:
> I don't know of anyone doing the VAX architecture in a FPGA.
>
> One of the most popular (and best) PDP-11 implementation in FPGA is the PDP2011 project of Sytse van Slooten at https://pdp2011.sytse.net/wordpress/
>
> There are a couple of others:
>
> W11 - <https://wfjm.github.io/home/w11/>
> POP11 - <http://labo.nshimizu.com/pop11.html>
> Verilog PDP-11 - <http://www.heeltoe.com/download/pdp11/README.html>
>
> Some haven't been active in a while. The PDP2011 project is active and Sytse is always working on improvements.

I wasn't even aware of the Verilog PDP-11, so you've inspred me to update my
webpage with links.

I thought that Tokai University had done a VAX-11/780 implementation, in
addition to the PDP-11 one you mention above. However, using Archive.org,
it looks like I may have been premature on listing that. They were
apparently at least working on it 15+ years ago.

I also have a line on the FPGA page that says "RT Logic" was reimplementing
the VAX in FPGA for HP, but the link is understandably dead.

Since the OP mentioned Twenex...
http://neil.franklin.ch/Projects/PDP-10/
http://fpgaretrocomputing.org/pdp10x/

Zane



Rich Alderson

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Jun 27, 2021, 2:17:43 PMJun 27
to
Dave.L...@f143.n3.z21.fsxnet (Dave Lightman) writes:

> The question was meant to ask if anyone knew of any recent FPGA projects that
> emulate PDP/VAX. I'd be interested to run twenex / vms on one to compare it
> to simh/charon.

Insert usual rant that "there's no such thing as 'a PDP'" in this context:
"Twenex" (i.e., TENEX or TOPS-20) runs on a specific architecture, the PDP-10,
not on some generic "PDP chip".

--
Rich Alderson ne...@alderson.users.panix.com
Audendum est, et veritas investiganda; quam etiamsi non assequamur,
omnino tamen proprius, quam nunc sumus, ad eam perveniemus.
--Galen

John Dallman

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Sep 24, 2021, 5:55:59 PMSep 24
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In article <3685462679@f143.n3.z21.fsxnet>,
Dave.L...@f143.n3.z21.fsxnet (Dave Lightman) wrote:

> The question was meant to ask if anyone knew of any recent FPGA
> projects that emulate PDP/VAX.

http://mail-index.netbsd.org/port-vax/2021/07/03/msg003899.html

John
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