Downtown Doug Brown

Hi Doug,

I have been trying to equip my Win 7 64 PC to run some old Analog Devices software that wants to communicate with an eval card via a parallel port. I installed a Rosewill RC303 PP PCI card which seems to function Ok, but it puts the port address up at 0xD030. Your Parallel Port Tester finds it and I can toggle all the pins. Thanks for a great piece of software. However the AD softwate does not seem to be able to deal with the non standard port address. I installed Windows Virtual Machine and their XP OS for it. Under XP running virtual the port appears at 378h according to the Device Manager but the AD software still does not find the port.

I tried to install your test software in the XP OS running virtual to see what was happening, but I have been unable to get it to load. It throws an error “unable to initialize”. I am using the recommended version of inpout32.dll. Do you know of anybody else’s experience of running your software in the virtualized XP OS?

Sorry for the long winded question. Thanks,

Dick Grubb

Hi Doug,

Would it be possible for me to take a look at your source code for this project? I downloaded your program and it works great with my card and relay board. I’m writing a simple program in c# to do the same thing. However when I run my program the led on the relay lights up then shuts off again. It should just stay lit. Any help would be great!

Thanks

Hi Nitzan,

Unfortunately I’ve never seen that problem before. I’m not exactly sure what would be causing it to happen. I’ve seen that happen in the past if I run a .NET program on a computer without .NET installed, but Windows 7 would come with .NET installed already. I could try to build some other binaries for you to help find exactly where it’s crashing, but I won’t be able to get around to that until next week if you’re interested.

Hi Arc,

I’ve gotten several requests and just haven’t had time to fully describe the detection until now. I just wrote a new blog post about how to detect parallel ports. It describes the algorithm I use in Parallel Port Tester. I hope this helps!

Hi Doug,
I tried to run the program on my Win XP 32-bit machine but get the error parallel port tester has encountered an error and needs to close. I have put the recommended 32-bit InpOut32.dll in the program directory.
Any ideas?

Hi Chris and Simone,

I am able to reproduce this problem in my VMware virtual machine running XP. I’ll see what I can do to fix it. I’m not sure exactly what’s causing it.

hi Doug,

it works! 😀 perfectly, it seems like my parallel port is working on XP too 😀

thank you very much!

mmm.. do u have a paypal account for donations? 😀 i owe you a beer

Unfortunately it does not have any switches for running automatically from a batch file. I’d recommend writing a small program that uses a library like Inpout32.dll to do it.

Have you tried directly connecting an input pin to ground to make it go black? If the input pins don’t go black when you ground them, I’m not sure what would cause that…

Have you verified the cards are set up to work in SPP (standard parallel port) mode? Other modes might not work the same way.

Hi Doug,

Do you have any experience, or can you offer any advice about running your Parallel Port Tester under Windows 10/64?

I’ve gotten tied up in a customer support snafu and was hoping to use your tester on their Win10 system to double-check what was actually getting written to the port.

Thanks,
Bruce

Hi again Bruce,

I just tested in a Windows 10 64-bit VMware virtual machine on a Linux guest with Inpout32 1.5.0.1, and Parallel Port Tester appears to work just fine. I will go ahead and update the compatibility information on this page to add Windows 10 as a compatible OS.

Will this work on dos 6.2 and/or windows 3.1?
We have an old 486 computer that runs a coil winder machine. We replace a crashed hard drive and reinstalled the software and files on the replacement drive, but the coil winder doesn’t run. We are trying to determine what the problem is and want to test the Parallel port.

I just bought a sunix pci parallel port board (SUN1989 chip) It installed fine on windows 10 and I can see it in device manager. When I try your parallel port tester it will not detect anything. I stepped through the code laid out in your other blog. I can find the port by name LPT3, but when it gets to finding the associated resources it find nothing. resourceQuery looks like ASSOCIATORS OF {Win32_PnPEntity.DeviceID=”SNXPCARD_ENUM\\SNXPCARD_PARPECP\\1FD4&1999_01001FD4_0000E4_PORT0″} WHERE ResultClass = Win32_PortResource.
I saw a comment about turning on legacy plug and play on the card, but no difference.

Do you have any tips for me?

Hi Doug,

If I look in device manager I find “SUNIX LPT port (LPT3)” but I could not find any resources shown. After some digging in the manual I finally noticed a screenshot showing that for the resources I had to look under multifuncton adapters which shows a “SUNIX 1-Port Parallel Card”. This node defines a resource number (0xC020) which when typed in your application dropdown gives me the parallelport status. It works, but it seems I will need a different resource query for this adapter than your code provides for. To bad I find WMI very untransparent

No, you were quite right about Win32_ParallelPort, that one does not work at all.
When I remove Win32_portresource from the where of the resourceQuery I get four results.
The classnames are as follows. CIM_Datafile, Win32_Bus, Win32_ComputerSystem and win32_systemDriver. (for the record I’m running win10 x64).

If I get more information about it I will forward it here. Thanks for replying

I downloaded wmiexplorer 2.0 from github and basically search for sunix and win32pnpentity. That got me two items
SELECT * FROM Win32_PnPEntity WHERE Caption like ‘%SUNIX%’
The first one class ports and the second one class multifunction (I believe this card is also sold in variant with a second parallel port and maybe some serial port).
Direct query for multifunction:
SELECT * FROM Win32_PnPEntity WHERE Caption like ‘%SUNIX%’ AND ClassGUID=”{4d36e971-e325-11ce-bfc1-08002be10318}”
I can than do an query for its associators (all learned from your post)
ASSOCIATORS OF {Win32_PnPEntity.DeviceID=”PCI\\VEN_1FD4&DEV_1999&SUBSYS_01001FD4&REV_00\\5&29DF5497&0&0000E4″}
and that gets me several port resources among which is the correct one.

I have little Idea about WMI an no clue how to “jump” from one device to the other. So I do not think this is to usefull for you, other than if you meet someone with a similar card. I will mail the manufacturer, but I don’t expect much from that.

Thanks again.

Hi Joe,

I don’t know off the top of my head, but you should be able to figure out the calling conventions of Inpout32 by looking at its header file. With that, it would be possible to call it from assembly. At the very least, you could just write a simple C program that calls it and then see what the generated assembly does.

Did you code a subroutine to handle the OUTP calls to the port? If so, can I see this subroutine?

Hi Doug,

Would you please give a “for dummies” type tutorial to a layman like myself, who has no programming skills, on how to interpret your software results? For example, which pins should be green and which black on a healthy parallel port?

I’m in a world of pain trying to get two CAD programs in a VMware Player Windows XP guest VM to recognise their respective Sentinel dongles (hardware locks/keys) plugged into a parallel PCI (not PCIe) card on the host. The card has jumpers, currently set to IRQ 278.

Frustratingly, both dongles work just fine on one computer, a Dell T7610 workstation, but refuse to get recognised on a newer T7910. Both machines have almost identical specs, identical PCI cards, and Windows 10 64-bit build 1809. By the way, I have also swapped out the PCI cards to make sure that neither was dead, but the problem persists. Help!

Brian

Thanks for the quick reply Doug. I think it’s best if I leave things alone then, since I do not have confidence in my own technical abilities. The last thing I want is to make things worse!

Brian

Hi Evan,

Thanks for your kind words! That isn’t really related to Parallel Port Tester as far as I can tell. The first thing I do when I open a port is read the current value of the registers in it and use it as the current state. So if it’s showing up as high when you open the app, it means it was already high before you opened it. I suspect something else is defaulting it to high.

Hi Pascal,

Hmm…I’ve never seen this happen before. Did you run InstallDriver.exe included with Inpout32 (in the Win32 directory)?

Hi Pascal,

When you download Inpout32 from the link I provided, it comes in a zip file. After extracting the zip file, there should be a folder called Win32 inside there. That folder contains the dll file you should use. It also contains a program called InstallDriver.exe that you should run to install the Inpout32 driver.

Hi Alireza,

Parallel Port Tester is actually written in C#. See http://www.highrez.co.uk/Downloads/InpOut32/default.htm for .NET example code.

Hey Jeff,

Basically there are three byte registers (for example, at 0x3000, 0x3001, and 0x3002 if the parallel port base address is 0x3000). Register 0 is the data register, register 1 is the status register, and register 2 is the control register. You have to do whatever your OS requires to do direct port access. I use InpOut32. Here is what I do when bitbanging:

The 8 bits of the data register are outputs (in standard SPP mode). You just set or clear the bits to change their state. 1 = high, 0 = low. That’s the easy part.
The status register contains the input status of busy (bit 7), ack (bit 6), paper out (bit 5), select in (bit 4), and error (bit 3). Bit 7 (busy) is inverted, so if it reads 1, the input is actually low. On the rest of them, 1 = high, 0 = low.
The control register contains the “bidirectional” signals. Select = bit 3, reset = bit 2, linefeed = bit 1, strobe = bit 0. All of them are inverted except for bit 2 (reset).

The bidirectional control register signals are interesting. They are supposed to have pullup resistors (although some cards don’t have them), so you can actually ask them to be driven low if you want. If they are high, they are basically simultaneously an input and a high output (because of the pullup resistors). On the inverted control signals, writing a 1 bit turns them into a low output, writing a 0 bit turns them into a pulled-up input. On the noninverted reset signal, writing a 1 bit turns it into a pulled-up input, writing a 0 bit turns it into a low output.

Note that because of this, the value you write into the control register might not match the value you read back. If you tell the reset pin to be a pulled-up input by writing a 1 to bit 2 of the control register, and ground is connected to it, you will read back a 0 bit indicating the input value is low even though you just wrote a 1.

It’s probably a good idea to make sure bits 4 and 5 of the control register are also written as zero to disable interrupts and the bidirectional data port (which is not always available).

Hope this helps! For which pin is which, this Wikipedia article works well.

Hey Joe,

I’m not aware of any issues with detecting parallel ports in the program anymore; that’s really weird. The original version had a problem where it would sometimes make a mistake when detecting port addresses. But either way, you can always manually type the base address into the selector box even if the program doesn’t detect it properly. It should be fine that only one I/O range is detected. If only one is available, it will pick the first one. So even in your first example when LPT3 doesn’t show up, you could still type 0xCCF8 into the box.

Is there any setting to tell the port to be in SPP mode?

Would you be willing to run this program and copy and paste the text it displays as a result? I used this when helping another user diagnose an issue with detecting different ports, which led to the release of version 1.0.0.1 where I stopped using Win32_ParallelPort to detect the ports and their addresses. Windows SmartScreen complains about it because it’s only been used by one person ever, but it’s completely safe.

https://www.downtowndougbrown.com/ParallelPortDiagnostics.exe

Either way, even if the port detection doesn’t work, Parallel Port Tester should still be able to control the pins on the port if you enter the base address manually. Is there a possibility that the card doesn’t like the motherboard you’re using it in or something? I’m grasping at straws at this point.

Hi Mike,

That’s strange! When you say nothing happens, are you saying that the main window of the Parallel Port Tester program doesn’t even appear? Do you have “.NET Framework 3.5 (includes .NET 2.0 and 3.0)” turned on in the “Turn Windows features on and off” settings? It needs to be on — but I’m guessing pretty much everyone already has that turned on. Just a shot in the dark!

Does the Win32_PnPEntity section from the ParallelPortDiagnostics.exe output contain any information about your parallel port? I stopped using Win32_ParallelPort because it returned invalid results for some other users. If you can get the main window to pop up, you should at least be able to manually enter 0xE100 as the base address in the lower right corner of the window in order to use it if it doesn’t automatically detect it.

Hi Bojan,

The problem is that USB-LPT adapters aren’t “real” parallel ports — they’re basically just simple adapters only meant for hooking up printers through USB. So when you get special gadgets like EEPROM programmers that are hooked up over USB, they aren’t printers, so the USB adapters don’t know how to use them. Unfortunately there is no workaround that I’m aware of. It has to be a “real” parallel port with the bulky DB-25 cable in order to work with every industrial/gadget parallel port application I have ever seen, and that includes the way that Parallel Port Tester controls it.

Hope this helps, although it’s not the answer you’re hoping for!
Doug

Dear Doug,

Thank you for your LPT tester. It has been very helpful. However, I had a couple of questions regarding the same. After selecting the port, I use the output buttons to change a particular pin. But that does not change the color of the input pins on the tester. Is that indicating of a problem with the port or the parallel port card? Additionally, one of the control buttons is only on/off halfway. Does it point towards the possibility that there may be something wrong with the port? Also, while testing the port, I had connected it to a parallel port cable. I would really appreciate your inputs.

Thank you.
Prashanti

Hi Doug,

Thank you for your prompt reply. Going by your advice, I connected two PCs with a parallel port cable to use the tester. And I changed the four control pins to output on one PC and input on the 2nd PC. When I toggle the control (output) pins on the first PC, the control (input) pins on the 2nd PC are automatically updated. However, if I toggle the other non-control (output) pins that does not reflect on the input pins of the 1st PC. Is that an issue or does that mean the port works?

Thank you,
Prashanti

Hi Doug,
Thank you the quick response. I will be using a multimeter for this purpose.

Thanks,
Prashanti

An interesting observation. I finally figured out what the Example program does and how to use it from Phils highrez website. I can read the LPT1 data port values all OK, but I cannot Write the data port values using the example program.
Any thoughts?????

Karin

Thanks for the reply Doug. A bit of background. Many years ago I wrote a bit of code, actually a very large bit of code, that used PortTalk on XP to access the parallel ports. I have since migrated to a Win 11 64 bit machine and PortTalk will not work on this machine. I have downloaded the example source code from Phil’s highrez website and compiled with Visual Studio 2022 professional. I can read the parallel port all OK but when I try to Write the code does nothing. It does not return any error codes when debugging, just does not write the bits to the data port. Obviously your code works OK on my Win 11 machine but there must be something I am missing. I am using the Example code verbatim, not making any changes at all. That code does exactly what you suggested above. I might add that the only way I can read the port is to use the Read LONG function the other two functions cause errors.
Karin

Hi, I’m looking for a tool that can capture data on a parallel port as it is being sent to a printer. Any suggestions?
Thanks!

Philip,

I fixed the URL of the diagnostics utility. The problem was this site is an https site, but the URL was http, so Chrome didn’t want to go to the link. Now the link is https so it should work. If all else fails, copy and paste the link into a new tab instead.

Unfortunately if it’s USB, it’s not going to have a hardware address. I’m not aware of any USB to parallel adapters that actually implement a full parallel port. USB doesn’t have any notion of an underlying mapped hardware address for a plugged-in device, so I don’t think it’s possible.

Hi,
I’m trying to use your LPT1 test software, but it always says I need to install .net 2.0 or higher when I run it. I have .net4 installed.

Doug, This program has saved my bacon! Very usefull!

Some PCI LPT cards have an extra control register at BASE+3 that is used to set the MODE (SPP, EPP, ECP) – it would be very usefull if your program supported that port as well.

I realize that it is a non-standard port and may vary from card to card but it is within the reserved range so shouldn’t cause any problems.

Regards,
David

Hi Doug!

Been trying to install this on a windows XP Professional 64 bit machine, not virtualized. Using the installer I get the following error during installation: “Failed to install InpOut32 driver. Try running InstallerDriver.exe manually.

Upon opening the program it states “Inpout32.dll was found, but the driver is not installed. If you’re on winodws Vista/7/newer, have you run InstallDriver.exe?”

Upon running InstallDriver.exe from the program file I once again get the following error: “Unable to install or open the 64bit InpoUt driver InpOutx64.sys. Please try running as administrator.”

Any help is appreciated, programs are being run as administrator.

Kevin.

Hi Doug – I like this program. I wanted to ask some noob questions regarding general parallel port testing. I have an iOmega Zip100 drive that I cannot get to work. I wanted to rule out communication problems between the unit and my PC. What would be some first steps? Does the tester software actually show activity while peripherals are running?

Very nice program.
I have a question (maybe 2) and a feature request.

1. I’m a bit confused about the description updates about the inpout.dll. Is it the case that the same dll will work for both 32 and 64 bit?
2. If not, does the program detect and select the dll to be used?

3. It seems the state of the data lines are static displaying the state at time of program launch. Is it possible to add a button to update the status of the data lines.

I’m attempting to refine my VB net (Visual Basic Express 2008) LPT control program for Jasper T Jowels which I acquired decades ago from a Chucky cheese auction. I have it working to a point but it would be really helpful to have a program such as yours update the data line states as my program toggles them. Your Pin 17 status lines update nicely.
Thanks, MIke.

Doug, thanks for the response.

1&2. I’m using VB Basic Express 2008. It will not work on a 64bit computer with the 32-bit DLL. (But does work with the 64bit DLL) So, obviously I’m not doing something right. But then I don’t know how to specify the program to be 32 bit.

3. Although space may be a problem, another suggestion would be to add to the pin descriptions which register they belong to, and what bit number they are within the register. For example, for pin 13 the description could something similar to:
“Select
Sta-4
Input”

And… It would be helpful to indicate which pins are inverted by computer hardware. It appears your program shows states as they result in computer and not what is actually on the pins (or maybe I have that reversed).

Despite all these suggestions, I want you to know that the program has been extremely helpful.

Just wanted to let you know that items 1&2 have been resolved.
Thanks, Mike D.

Hi fishbeetle,

Unfortunately, the USB LPT ports aren’t real parallel ports. USB has no way of mapping to a physical address on the computer like these dongles need, so they only really support printers.

Your best bet is probably to find an older computer that has a built-in parallel port. If it’s a super old product, I wonder if someone has developed a crack to avoid needing the dongle. Seems like it would be reasonable to bypass the protection as a legit owner.

Hi TC, unfortunately I don’t know how to monitor reads/writes in Windows. I wonder if there is some kind of external data logger you could wire up to the port and record every time it changes, and then toggle it in a Windows 10 computer on a regular interval. What about a known good Windows XP computer constantly reading a pin as an input and logging when it changes?