How does one do "parallel passthrough" on Win7 host?

[PipsTwiddles]

I have a Windows 7 host, and I have a Windows XP (SP2) guest on VirtualBox 4.2.18 which needs to use the physical parallel cable of the host. I have an application which only runs on up to WinXP SP2 and needs to communicate to a JTAG interface on a device which is connected over a parallel cable.

Is there a guide on "parallel passthrough", on how to pass through access to the parallel port to the WinXP guest?

I can only find a way-too-brief mention of '--lptmode<1-N> <Device>' and '--lpt<1-N> <I/O base> <IRQ>' in the user manual, which doesn't really explain anything.

When I had WinXP directly on the host, all I did with the application installed was to click on "connect" inside the app, and it worked. No settings or anything. - I only have one physical parallel connector on the back of the machine. But now I need Windows 7 on the host.

Any help would be gratefully appreciated.

[mpack]

Howto: Enabling and Configuring Parallel (LPTx) Ports.

However, I wouldn't have too much faith in a JTAG interface working in a VM.