[Info-vax] SimH with framebuffer and hobbyist kit?

Wed Apr 10 06:11:32 EDT 2013

On Wednesday, April 3, 2013 1:59:15 AM UTC+2, Vertis Sidus wrote:
> On 2013-04-02, John E. Malmberg <wb8tyw at qsl.network> wrote:
> 
> > On 4/2/2013 4:59 PM, Vertis Sidus wrote:
> 
> >> On 2013-04-02, Bob Koehler <koehler at eisner.nospam.encompasserve.org> wrote:
> 
> >>> In article <slrn3vfsklkdre.pc1.vrtsds at sdf.lonestar.org>, Vertis Sidus <vrtsds at sdf.org> writes:
> 
> >>>> I'd like to use DECwindows in an emulated framebuffer, but the only option I
> 
> >>>> can find for that is the VAXstation 2000 emulator at
> 
> >>>>
> 
> >>>>    http://www.9track.net/simh/vax410
> 
> >>>>
> 
> >>>> This is a rather limited system! From what I've read, it really wants VMS
> 
> >>>> 4.x or so, but unfortunately all I have is the current 7.3 hobbyist kit. Is
> 
> >>>> it at all possible for VMS 7.3, with DECwindows, to run in this emulator? Or,
> 
> >>>> is there another framebuffer emulator option that I don't know about?
> 
> >
> 
> > The author of that variant of SimH has posted on this forum about it, 
> 
> > and you might contact him to get the source.
> 
> 
> 
> I may do that, but I'd like to at least try to get it
> 
> running as-is first. I haven't done any real programming in
> 
> years, so I wouldn't be surprised if it's completely beyond
> 
> my ken.
> 
> 
> 
> >> Not so lucky in the case of this particular emulator. As
> 
> >> near as I can tell, the memory won't go above 16MB, and the
> 
> >> only supported storage is two hard drives (RD31, RD32,
> 
> >> RD53, or RD54) and a floppy drive. No CD-ROM, of course. I
> 
> >> don't even get a tape drive.
> 
> >
> 
> > Even with those limitations, I think I could get VMS 7.3 to run on it as 
> 
> > a LAVC client.
> 
> 
> 
> I tried that once, months ago. It died horribly on startup,
> 
> because I don't know what I'm doing. :)
> 
> 
> 
> That's something I plan to try again, later, after a lot of
> 
> research.
> 
> 
> 
> > I used to run a farm of VS2000s for a display only application.  The 
> 
> > VS2000s network booted VMS.  Oh, and I only had 4 to 6 MB of ram on 
> 
> > them.  The actual application being displayed on them ran on a VAX 
> 
> > 4000-500.  A fake keyboard plug on them allowed unattended booting.
> 
> >
> 
> > Way below supported specification, but ran for years.
> 
> 
> 
> That's encouraging to hear!
> 
> 
> 
> > The problem is that the framebuffer in the emulator is too primitive for 
> 
> > DecWindows Motif to support.  You need at least 8 bit graphics.
> 
> 
> 
> That's fine. I never really liked Motif anyway. :)
> 
> 
> 
> I guess that may be another reason I need an old kit,
> 
> though...
> 
> 
> 
> > But that still is not good enough.  GTK+ needs at least 24 bit color.
> 
> > And your performance will be probably slow.
> 
> 
> 
> It hadn't even occurred to me to try to get GTK+ working in
> 
> this thing.
> 
> 
> 
> > Now some answers to issues raised on your previous posts.
> 
> >
> 
> > 1. A modern Linux running in a VM using paravirtualized I/O drivers has 
> 
> > negligible overhead.
> 
> >
> 
> > So it is cheap to create a Linux VM to dedicate to running Simh.  Set up 
> 
> > for emulated NICs on the VM.  2 for the Linux host, 2 for SimH.
> 
> > On the host and the emulated system, you have one NIC each for a private 
> 
> > LAN and one for access to the external network.  Using a VM makes this 
> 
> > trivial to set up.
> 
> >
> 
> > You can set up VMs to cause performance loads, but the current Linux 
> 
> > kernels detect that they are running in an emulator and just turn many 
> 
> > operations over to the host instead of simulating them like was done in 
> 
> > ancient times.
> 
> 
> 
> Actually, I only mentioned the challenge of getting VMS to
> 
> network with the host as a general response to the "why do
> 
> you want a framebuffer? just use X!" meme. I've noticed
> 
> that when novices try to actually get help with setting X
> 
> up, they quite often get a response of "why are you trying
> 
> to do something that hard when you've only just gotten
> 
> started?"
> 
> 
> 
> Networking between VMS and the host is a problem that, for
> 
> myself, I've pretty much solved - either with VMs or with
> 
> taptap and bridging, depending on the circumstances.
> 
> 
> 
> > 2. SimH built with netorking support can handle 512 MB of emulated ram, 
> 
> > access to a CD-ROM image controlled by the emulator, and emulated disks, 
> 
> > probably up to a terabyte.  I have only used about 10 GB disks myself.
> 
> 
> 
> These are beautiful and useful features and I deeply wish
> 
> the VS2000 version of SimH had them.
> 
> 
> 
> In particular, extending the system memory past 64M (I
> 
> think) depends on using the ka655x.bin that comes with
> 
> SimH - it's a specially modified version of ka655.bin for
> 
> that specific version. I don't think any similar
> 
> modification of ka410.bin exists.
> 
> 
> 
> And the VS2000 emulator seems to only support four models
> 
> of hard drive and two models of floppy drive. There's no
> 
> RAanything, much less RAUSER, and the SCSI controller
> 
> needed for tape is listed as unimplemented.
> 
> 
> 
> Entering anything else gets a "Non-existent parameter"
> 
> error.
> 
> 
> 
> > 3. For X11, HP TCP/IP does not support SSH tunneling, so you have to 
> 
> > lower the security of the X server.  But you only have to do it on your 
> 
> > private internal network that is local to your system running a VM.  Or 
> 
> > it may be that of the Process Software TCP/IP products can be used to 
> 
> > provide SSH tunneling, and they have a hobbyist program.
> 
> 
> 
> Is that MultiNet? I actually have that, but I haven't quite
> 
> got round to installing it yet. (The kit is huge!)
> 
> 
> 
> > 4. You will need to get VMS specific fonts on the X-Server.  The VAX X11 
> 
> > software does not have a compatible font server.  The Alpha and IA64 
> 
> > versions can serve fonts.  So consider an Alpha emulator.  A Windows VM 
> 
> > will use a bit more resources than Linux.  I have not tried running an 
> 
> > Alpha emulator on Linux yet.
> 
> 
> 
> I've had some success with Alpha emulation on Linux. The
> 
> hardest part of setting it up was connecting to the
> 
> console. I don't quite remember how I solved that, but
> 
> I'm pretty sure I mentioned it here at the time.
> 
> 
> 
> As for fonts.. wow. I just don't know. I'll get to that
> 
> later, I guess.
> 
> 
> 
> >
> 
> > Regards,
> 
> > -John
> 
> > wb8tyw at qsl.network
> 
> > Personal Opinion Only
> 
> >
> 
> 
> 
> Thank you for your insight.
> 
> 
> 
> -- 
> 
> vrtsds at sdf.org
> 
> SDF Public Access UNIX System - http://sdf.org

Hi,

Stromasys has a VCB02 for their VAX emulators, it's the only colour framebuffer I know of, if a VCB02 suits your needs and it will cost you a little of course.

^P