Parallel port problem

[Al_change_little_to_big]

Always nice to start with some alliteration

I have a parallel port dongle for some old 16 bit SCADA software
(intellution fix v5.6) and this works fine on a Dell latitude laptop running
XP pro.

When I came to try it on desktop PC's the SCADA startup screen freezes when
trying to access the dongle.

One of the desktops is running the same version of XP Pro and uses the same
parallel port (and ParVDM.sys) file. The other a running either xp pro sp1,
xp pro sp2 or xp home sp2.

If I disable the parallel port in Device Manager the startup screen is fine
and reports that the dongle is missing (and allows demo mode to run)

I've tried altering BIOS settings and driver settings (use interrupt etc)
but to no avail

I also tried using user port drivers (PortTalk, UserPort) but I suspect part
of the problem with them may be that the startup screen then loads DLL's or
other exe's

I've contacted Intellution (the SCADA programmers) and they just said sorry
our stuff doesn't run on XP unless you give us £10,000 for our nice new one.

Any ideas anyone?

Info

Dell latitude - this one works

XP Pro V5.1 build 2600 xpclnt_qfe 010827-1803

parport.sys Version 5.1.2600.0 xpclient.010817-1148

parvdm.sys Version 5.1.2600.0 xpclient.010817-1148


Dell optiplex GX260 - this one doesn't work

XP Pro V5.1 build 2600 xpclnt_qfe 010827-1803

parport.sys Version 5.1.2600.0 xpclient.010817-1148

parvdm.sys Version 5.1.2600.0 xpclient.010817-1148

 

[Cari \(MS-MVP\)]

What is the parallel port set to in the BIOS? EPP, LPT or something else.

 

[Al_change_little_to_big]

Hi,

the port on the laptop (which works) is set to ECP

the port on the desktop with the same drivers (which doesn't work) is also
set to ECP

 

[Al_change_little_to_big]

A breakthrough!

I realised that the only unique thing about the laptop that works is the
fact that is has an old HP Laserjet 4 attached (and consequently its driver
which specifies LPT1 as the port) when I set up this driver (but no printer
attached) on my XP Home PC the dongle checking code now works (I haven't
checked it with the dongle as its at work but I'm sure it will be OK).

If I then disable the HP, or specify another port, the dongle code then
freezes again so for some reason it needs this hardware link.

Incidentally the printer queue for the HP shows 40 single byte print jobs
when the dongle program starts but I can live with that.

Thanks for your help