Digitrac (logic analyzer) on XP

March 21, 2006 8:31 PM

Anyone with experience running Digitrac (logic analyzer) on XP?

I know XP is not friendly with IO control on parallel ports. I went to all (the few) pages Google turned up for Digitrac and accessing parallel ports on XP. Two programs came up (with direct reference to Digitrac) Porttalk and UserPort. I have installed both.
I can get Digitrac to start without getting "Privileged instruction" error, but it is not detecting my input signals, which are running through a 74HC245.
Under Printer Port Properties I have LPT1 set to range 0378-037B and use any interrupt assigned to port.
In Digitrac settings I have Input Port set to 378. I have tried each of the compatibility settings and none.
When I try using UserPort I have All User Mode set to 378-37B.
When I try using Porttalk I have the target line of my shortcut set to "C:\laz\AllowIo.exe digitrac /a". Setting to 378 instead of /a (all) gives "Privileged instruction" error.
Not sure what I am missing here. Any help is appreciated.

posted by sailormouth to computers & internet (8 comments total)

Try changing the port settings in the BIOS.

EPP, ECP, SDP... and so on. It should be under "Integrated Peripherals" or some such. It maybe listed as "Parallel Port Mode".
posted by ed\26h at 4:11 AM on March 22, 2006

I forgot to mention that I checked BIOS and port is set to bidirectional.
posted by sailormouth at 10:23 AM on March 22, 2006

I realize this is basic stuff, but you didn't say you had one, so to make sure: you are using a good quality IEEE 1284 parallel port cable, correct? Not all parallel cables are IEEE 1284 compliant, nor are all of them high quality. Within reason a shorter run is better for signal strength, although you should be good up to the 25' maximum recommended length using a proper cable.

Also, can you boot your machine into another OS that is supported (e.g. a Linux variant or FreeDOS) and see if your setup works there. Basically, there's a need to know that it's the XP interface that's failing rather than another culprit, unless you have already ruled out all other influences.
posted by mdevore at 11:19 AM on March 22, 2006

I am going to pickup another cable today to try. I'm using my old printer cable (Belkin db25 to centronics).
I was considering loading 98 (which would eleviate the IO permissions problem) but that gets into an area I have not done before, dual boot. I do not have enough room on my primary HD but plenty on my secondary.
posted by sailormouth at 11:54 AM on March 22, 2006

Well, if you have a CD-ROM you can boot a Linux like Knoppix or FreeDOS and not mess around with a hard disk install. Or a USB flash drive, if your computer supports booting a USB device. Linux support might be an issue for older hardware/software, but DOS has no port protections and enjoys the largest hardware and software support for older and DIY hookups.
posted by mdevore at 12:04 PM on March 22, 2006

This is the programmer's site. It runs on 95, 98, ME w/o a hiccup and on 2k, NT, XP with work arounds.
I did load DOSbox to run some programs to check port locations/settings. I even tried to run it in DOSbox but got a "This runs on win32 not dos" message. I do have a Knoppix cd but I do not think it'll be much help.
posted by sailormouth at 12:43 PM on March 22, 2006

Since the programmer can make it work with XP, that indicates your problem lies elsewhere than a general XP incompatibility, either with your hardware or your specific environment XP conflicting. Besides testing the cabling, it would be useful if you could get things to work with another OS, since that would either narrow down the problem to your specific XP setup instead of hardware/interface problems, or rule it out.

Anyway, besides what's already been suggested, I got nothing.
posted by mdevore at 1:09 PM on March 22, 2006

Thanks mdevore the cable was the problem.
posted by sailormouth at 7:25 AM on March 23, 2006