Paralle ECP LPT port on Windows guest

[CorsariF]

Hello to all of this great community

I have Lenovo i5 PC with still the LPT port which is ECP

with reference to this thread viewtopic.php?t=54187

I kindly ask how to enable an ECP LPT port to pass through and become available to a virtualized Windows XP (either if I don't think the Windows version could make any difference)

Before to issue these commands viewtopic.php?p=248885#p248885 I have read the settings of the physical ECP LPT port in the Windows 10 host, they are set accordingly and so those are not the issue (hopefully)

Virtualbox is the current version 7.0.10

THE BIG ISSUE

is that as soon I issue the commands that modify the .vbox XML file and right after I attempt to boot the Windows Xp VM, the boot fails with the Guru error

THE NASTY BEHAVIOR

is that either if i restore a backup of the Windows XP VM' config *.vbox file, the Windows Xp VM boot will keep on failing and will never boot anymore.

Unique solution, restore the VM backup I have made before to do these experiments

Thank you for any hint
Robert

[mpack]

If you have read the thread you reference then you should understand that the address and IRQ parameters passed to the guest have nothing to do with the physical parameters of the host. The only goal of those parameters is to choose what guest LPT port to emulate, and in practice that is nearly always LPT1. The associated tutorial tells you exactly this and gives you exact commands. The only thing you have to provide is the name of the host port that guest data should be redirected to.

The tutorial already has everything I could say here, honed for clarity over many years. Please read it again.

I frankly don't believe that you are restoring the .vbox file correctly to avoid the crash. I suspect you are misnaming the file because you have a Windows host which is configured to hide filename extensions.

[CorsariF]

Hello

thank you for the hints

I'm 55 and always worked in the IT , on my Windows , files extensions are always enabled, either if I restore the previously (working state) .vbox saved file, the VM XP won't start anymore, but this is not the issue and not the topic

I have the whole VM folder saved and so I restore it at every failed attempt, it is only 4.5GB .vdi

The port is ECP and there are threads out there , like this viewtopic.php?p=378017#p378017 , that tells ECP has been an issue

Maybe after that last working version, this has been totally abandoned and ECP wont' really work anymore, that is why the title of this thread specifies "ECP LPT"

[CorsariF]

Ok

luckily in the BIOS there is the LPT mode setting

I have changed the BIOS setting of the LPT port to normal and now the same instructions are working

Windows Xp device manager shows the LPT1 port available

What a nasty news ... I must abandon VirtualBox for something else, because I need the LPT ECP (extended capability port) otherwise one Dongle that should enable the unique needed application to run ... it is not recognized ... what an awful news

Unbeliavable

[mpack]

No, as far as I'm aware the LPT passthrough feature has not been abandoned.

That said, even when people were directly using physical LPT they were notoriously finicky and unreliable. Even when the port claimed to support ECP you couldn't know if it was done correctly.

And VirtualBox wouldn't care that the host port is ECP: it's a passthrough feature, so whatever features the host hardware has, AFAIK that's what the guest should see. E.g. there is no guest emulation of ECP on non-ECP hosts.

[CorsariF]

Believe me , it doesn't work (unfortunately)

I run the same identical commands with according LPT port address and IRQ (checked in the host hardware device settings)

The virtual machine doesn't start if ECP in the BIOS is enabled and, nevertheless, the VDI gets some sort of damage

[CorsariF]

Info: The PC is a Lenovo ThinkCentre

[CorsariF]

Also see this

https://www.virtualbox.org/ticket/16127

There are behaviors behind LPT ECP ports

[CorsariF]

I have read carefully this

viewtopic.php?f=35&t=54187

The unique thing I can and will test tomorrow is to disable interrupt , this is possible in device management

For the rest I'd say tried everything

[CorsariF]

Any chance to get a good hint?

Thank you

[scottgus1]

All we have on the subject is the "Enabling and Configuring Parallel (LPTx) Ports" tutorial that you've already found. If you followed that tutorial exactly, then this is as far as we can take you.

If your parallel device still does not work, it may not be possible to run it in a Virtualbox VM.

Please see your Private Messages.

[CorsariF]

Ok
Sad
Thank you

[klaus]

The parallel port passthrough code on Windows host was disabled with VirtualBox 7.0.0. Since then it gives this not so great diagnostics (guru on VM start). It was never officially supported...