Windows versions that will work with PCRTA

[Rodon]

Hello.

I have a few questions about the PCRTA. I am considering buying one from a friend and want to know about the software. I believe his is about 4 years old or so.

Is there updated software available for this meter?

Can I run it under Windows XP or Windows 98SE?

Where is the ftp site for this software and what are the user name and passwords for this site?

Any info would be great.

[Mike Frost]

The pcRTA version 2.30 software was released in July of 2001, and it will function under the following operating systems:

Windows 95/98/98SE/ME
Windows NT4/2000/XP

The software is available in the Downloads > Program Updates section of the LinearX website at:

http://www.linearx.com/downloads/DownloadUpdatesTop.htm

[Matthew]

I am running the PCrta in a PAC IV under XP. I have no problems except for the %$#@ COM port timeout error. I used to use the correct driver but that got zapped when I installed XP. Any new drivers or where I can get the old one if it still works.

And is their a new Manual out for the PCrta. I have one which is severly dog eared.

Many Thanks

[cstrahm]

If you are using a PAC4, there are no drivers involved. It simply uses the serial COM port. We provide a com port driver replacement for Win9X that solves a bug in the stock com driver. However that is not needed under NT.

What is the speed/kind of computer? It is possible you could get a time out error if the computer cannot keep up, or you are doing something else in a different app, or opening other dialogs in the program while the analyzer is running. Have you also tried different Baud settings? If it is a speed bottle neck problem then you should see it go away at lower baud rates.

If you want a PDF of the manual, send us an email directly to support@linearx.com

[Matthew]

I am running XP on a DELL Laptop with a 440MHz Celeron so I don't thing speed is the problem. I am also running the PCrta 2.3 SW on it's own so no CPU bottlenecks there.

I will try the lower BAUD rates and let you know.

Thanks for the info

[Matthew]

I am still getting the error despite changing the BAUD rates.

Any assistance would be most helpful as the link always bombs at the wrong time and is getting a bit frustrating.

Many thanks

[Mike Frost]

There is probably a driver chewing up your CPU bandwidth.

You can check this by opening System Monitor under Programs > Accessories > System Tools. If the CPU is running at 50% to 75% utilization when you are not touching the computer, then you can be fairly certain that it is the touchpad mouse driver to blame. Use an external PS/2 mouse and remove the driver for the touchpad mouse.

[Rodon]

Not sure if you want member input but.....

I had a similar problem when I first used XP and the PCRTA 2.30. Here is what I did.

I went into my hardware settings in XP (My Computer, view system information, Hardware, Device Manager) . Double click ports, double click the correct com port, and then go to port settings. I raised my port speed to 128000. Also click on resource and write down the I/O range and make sure there are no conflicts.

I then went to the PCRTA application, Utilities, PAC Interface, selected the the correct com interface, verified the addr was in the same range as the I/O range that was listed for this com port in XP. Then I selected 57,600. Then Start Link and begin the calibration.

Try that and let me know if it works for you.

I would try this before disabling other devices like the touchpad. touchpads are on comA usually and are on a different I/O bus than the external ports.

[Matthew]

Mike , Rodon thanks for your input. I havent tried either yet but I will let you know once I have. Hopefully tonight as I have a client tomorrow.

Matt

[Matthew]

Hi Guys

Have tried increasing the baud setting on the com port to 128000 but still get bumped off the connection after about 1-2 minutes.

I also tried to diconnect the laptop mouse with no success. Any other suggestions?

Matt

[cstrahm]

It sounds like you have tried about everything. If you are getting this kind of problem even at low baud rates, then something is very wrong. We can run the pcRTA in continuous measurements on a old i486 for 24 hours at the highest baud with no problem.

I assume you have tried other cables to eliminate the connection itself as a source of the problem.

If the PAC unit works fine with other computers, but does not work correctly with that one machine, then it may well be a defect in that particular model or unit.

Problems with the hardware chips that implement the COM ports in some laptops are well known. It is a fact that IBM and others have had defective I/O chips in their various models of laptops. Have you contacted the manf to ask them about reported problems with that model's COM ports? You also might wish to search the web and see if there are other bad reports about COM port usage for your model.

[Matthew]

I will try it with another PC and see if I get similar results. Any date for a USB upgrade to the PAC IV ;) .

[cstrahm]

There are no plans at the moment to do a USB version of the PAC4. And if you think that having a USB interface is going to eliminate all problems, just do a search on the web for USB problems. There are probably more bugs reported on that than there are COM port problems by far. Such is life in the PC world.

[Rodon]

Different COM port
New Cable
Shorter cable
Maybe try serial copying of large files (ones that will be longer than 3 minutes to copy) on that port
Maybe look for a serial port analyzer to watch for errors or noise on the port.
Try a USB to Serial adapter
Try new PC
Try another slot in the PAC four
Try other jumper settings
Look for kinks in cable or breaks



Just spouting off ideas to try

[Matthew]

Tried the pcRTA & PAC IV on my desktop and no problems so it must be the serial port on the DELL.

I am downloading new BIOS and new pointing device updates from DELL to see if it will help. They have no updates for the Serial ports.

I ran diagnostics on the COM ports on the DELL and they passed so who knows.

The exact error I get is:

PAC3: DLL COM Port Error
RX-Timeout

in a pcRTA Message box in the middle of the screen.

I have a DELL Latitude CPt S

[cstrahm]

That's exactly what I expected. The laptop is the problem. We see that all too often. These problems always seem to be on laptops and never on desktop machines.

Running simple diagnostics on the COM port really won't tell you anything, other than the UART registers are there and responding. It is not checking TX/RX in/out of the port. To do that you need a full test with a loopback connector. Even then you would need to send large quantities of data back and forth to fully exercise the buffers. Actually the PAC4 is one of the best diag tools for checking com ports.

There are so many ways to use an RS232 port, that testing the same operating mode is also very important. The PAC units use full hardware handshaking with parity checking. If a COM port has any problems with this, you get an error. Mice and other low performance devices generally use software handshaking and may never see problems that exist in the COM hardware for other operating modes.

You might try changing the COM/UART settings in your Control Panel. Typically there are adjustments for buffer size. But from our experience when a laptop has these kinds of problems it is due to hardware defects in the I/O chip. There is no way to fix it.

[Matthew]

I am happy to report that the problem is over, well at least the one I mantioned. I still get the odd RX overrun error and the COM port shuts down but it happens every now and then nothing like before.

I downloaded the XP update for the touch pad on the laptop as well as a BIOS update for the machine. I installed both and hey no more problem. I can't tell which solution solved the problem as I did both without testing.

I do however notice that the pcRTA maxes the CPU out to 100% while in Test mode.

I would like to caution all out there who are considering buying a new Laptop. Try it with the PAC IV before you buy!!!

Any other tips which would stop the RX-Overrun would be helpful.

Thanks to all who helped I appreciate it!

[cstrahm]

If you are getting Overrun errors, that means your computer can't keep up. More data is coming in faster than the CPU can process it. Processing means floating point calculations and screen repaints.

My guess is that the laptop has a limited graphics processor, and relies more heavily on the CPU to do many raster calculations. If you watch the screen redraws on laptops vs. desktop machines they are often visibly slower. Redrawing the bar graph readout is basically an animation algorithm. It takes a significant amount of graphics processing.

How much work that is for the CPU all depends on how much work the GPU does. If the GPU is weak, then the graphics overhead falls on the CPU. If the GPU is highly accelerated then the CPU sees little graphics overhead.

As I said before, a 486 machine with a modest video card has no problem at all handling the processing. But a laptop with a non accelerated GPU must have a much faster CPU.

[Matthew]

Thanks for the info Chris.

Although it may not save me a little aggrivation now it will help me when buying a replacement laptop.

BTW have you ever considered doing a 1/6 octave or a 1/12 octave RTA?

[cstrahm]

I forgot to mention before, that many people get around the problems with their built-in laptop COM ports by adding a COM port on a PCMCIA card, USB, etc. Some of these have strange UART register setups that can be a problem too, but they also have solved many problems as well.

The next analyzer will be able to do those kinds of things. Of course if you want higher resolution, then that is exactly what LMS is for. You can get the equivalent of 1/64 octave with that. But it is a swept sine wave analyzer not a noise analyzer. Different kinds of animals.

[Ray]

We recently purchased a Dell Lattitude C640 which has a Pentium 4-M 1.7GHz processor. We are running Windows 2000 and are having the same problem with RX Overrun.

Surely the pcRTA software can be changed so that it reconnects automatically if an overrun occurs. Having an overrun is not really a problem, it is having to open the Utilities and PAC interface dialogs and restart the link manually that is the real pain.

Also the suggestion that we go out and test each new laptop for compatibility with the pcRTA software is quite ridiculous. How many computer retailers will allow a customer to install their own software and then hook it up to some third party equipment to test the system BEFORE they buy? Certainly none in this part of the world.

Please just add an auto link restart option to pcRTA software.