jawi edited this page Sep 11, 2014 · 13 revisions

This page tries to answer some frequently asked questions on the OLS client. See the different categories for more information.

Table of Contents


Your client does not run; OSX tells me that the application is "damaged and can't be opened."
OSX 10.8 introduced a new security feature called Gatekeeper, which is enabled by default and prevents applications distributed outside of the Mac App Store from launching. There is a workaround for this by allowing applications to be installed from anywhere, see http://www.yourkit.com/download/mountain_lion.html. To summarize, you need to open "System Preferences > Security & Privacy" and set "Allow applications downloaded from:" (on the General tab) to "Anywhere". After the application is run at least once(!), you can revert this change if desired.
Your client does not run. It cannot find the classes and/or complaints about incorrect version numbers!
The OLS client is written in Java 7 and runs on Java 6, 7 and 8 (be sure to use 0.9.7 SP1 when using Java 8!). Ensure you have installed the latest Java version (currently 8) on your system. For Windows/Linux, see this page; for OSX, see this knowledge base item and this knowledge base item, or use your regular Software Update mechanism.
When running your client on Linux, the only thing I see is a large gray rectangle, nothing more!
You are probably running a "non-re-parenting window manager", such as Awesome. There are several workarounds: either set the environment setting AWT_TOOLKIT=MToolkit; export AWT_TOOLKIT, or use a tool like wmname to let your JVM believe it is running on a different window manager. See this page for more details on how to do that;
I get an error upon capturing about There is an incompatible JNA native library installed on this system!
There is already an JNA library present on your system that is not compatible with the one supplied in OLS client. To work around this, you can add the property -Djna.nosys=true to the startup script of the client, e.g., java $MEMSETTINGS -Djna.nosys=true -Dnl.lxtreme.ols.bundle.dir="$PLUGINDIR" -DPlastic.defaultTheme=SkyBluer -cp "$CLASSPATH" nl.lxtreme.ols.runner.Runner in either run.bat or run.sh. Note: this is fixed in 0.9.7!
Your client crashes with an OutOfMemoryException on heap space!
If you're performing large captures (e.g. with RLE turned on) it can be that the client hasn't enough memory by default to store all samples. For now, you can enlarge the memory settings by adding -Xmx1024m to the Java command in the run.bat, run.sh, or the VMOptions option in your Info.plist. Note: As of 0.9.2, these options are added by default!
Does your client store the settings I made between sessions?
Yes it does! All settings made in dialogs are saved between sessions.
Can I just remove these implicit user settings file?
Yes, this is possible. The client does not depend on its contents. Be aware that it will recreate this file each time you end the client.
Where can I find these implicit user settings? Where do you store them?
It depends on your host platform:
  • On Mac OS, they are stored in ~/Library/Preferences/nl.lxtreme.ols.client.Application;
  • On Linux/Solaris, they are stored in ~/.nl.lxtreme.ols.client.settings;
  • On Windows, they are stored either in:
    • %LOCALAPPDATA%\nl.lxtreme.ols.client.properties, or
    • %APPDATA%\nl.lxtreme.ols.client.properties, or
    • <root>\Documents and Settings\<username>\nl.lxtreme.ols.client.properties.


I cannot capture anything; nothing happens (perhaps exceptions in the console)!
If you've played with the original SUMP client, you installed the RXTX libraries separately. Try deleting the RXTX libraries from your Java installation as they might interfere with the libraries included with this client.
My OLS-device isn't recognized by your client. It does not appear in the list of devices!
Try entering the device name of your device (e.g. /dev/ttyACM0, /dev/tty.usbmodemfd142, or COM13) directly as port name. Note: in 0.9.5 this will be fixed!
I've got multiple serial devices that go mad when/no longer react after opening the device list!
The RXTX library shortly opens and closes each port in its detection routines. Try entering the device name directly as port name.
Opening the device list takes a very long time!
The RXTX library probes lists of possible devices, for example, on Windows, it tries to open COM1 through COM256(!). Try entring the device name directly as port name instead of selecting it from the drop down.

User interface

How can I remove (all) cursors?
Removing a cursor is done by opening the context menu, and selecting the cursor again. This will remove the cursor. To remove all cursors, use the "remove all cursors" option from the context menu.
How can I remove annotations from the tools I've run?
Removing the annotations is done by choosing the "Remove annotations" from the "Diagram" menu.
Not all channel groups are shown in my acquisition result!
Check whether all desired channel groups are enabled the "Diagram mode settings" (see "Diagram" menu).
Why are there two ways of selecting channel groups, one in the "Diagram mode settings" and one in the acquisition settings?
The first denotes how the acquisition results should be displayed, that is, with or without the byte value and/or scope. The chosen channel groups in the acquisition settings denotes how much data is acquired from the device.


How can I decode only parts of my captured signal(s)?
Mark the area you want to decode with cursors 1 and 2; this will cause most decoding tools to decode only that part of your signals.
The measurement tool is broken! I've captured a clock signal of a known frequency, but the measurement tool calculates a different frequency!
When capturing a clock signal asynchronously, you are introducing a certain "error" in your capture. The sample moment can deviate with a certain time-delta for each captured clock cycle. An example: suppose you are capturing a 16MHz clock signal at 100MHz. A single period would take 6.25 samples (= 100/16). However, since sampling is done discretely, your capture will only have 6 or 7 samples in a single period, resulting in a signal of somewhere between 14.29MHz (= 100/7) and 16.666MHz (= 100/6). Only when capturing a clock source that is an exact multiple of your sampling frequency (say: 1MHz captured at 100MHz), you can determine the exact clock frequency. In 0.9.4, the measurement tool will display the 'error' of its measurement.
Ok, but how can I verify the frequency of a clock/oscillator more precisely?
A logic analyzer is not the best tool to do this. Instead, you should use a frequency counter instead.