Channel Access Markup Language Plugin Installation and Configuration Instructions

Supported Operating Systems

Windows support

Note: CAML does not support Internet Explorer, which is not compliant to applicable W3C standards. CAML does work with Firefox, Chrome and Safari. ORNL and CosyLabs, the originators of CAML, are working on IE support.

If you haven't yet installed the Channel Access (CAML) browser plugin,

download this executable binary, exit the browser, and run ARD_webCA_plugin_installer.exe. You will need admin privileges on the machine. Start a new browser and view the page again. If the installation fails or CAML annoys you somehow, download and run the Uninstaller. The Installer works with Windows XP and EPICS R3-14-9 on x86 systems.

How to tell if the CAML plug-in is installed on Windows:

Go to the browser's "Tools ... Add-ons ... Plugins" menu to see if "EPICS Channel Access Plug-In 1.2.0" is listed. Alternatively check C:\\Program Files\Mozilla Firefox\Plugins to see if npca.dll is present. On Windows, the installer must allow add a line describing the plug-in to the Registry.

If you have installed the Channel Access (CAML) browser plugin,

and still don't see updating PVs, then your EPICS environment variables need to be reset to ARD values and then you will need to restart the browser for the changes to take effect. In order to view the LCLS PVs, you will need to revert the environment variables to those settings. Here are some .exe programs that accomplish the task for users with and without administrative privileges. To see if the environment variables are set properly, open the Control Panel, choose System, go to the Advanced tab and click "Environment Variables." With ARD settings, you should see opi00gtw04 as the EPICS_CA_SERVER value, while with LCLS settings the value should be lcls-prod01.

Linux support:

If you haven't yet installed the Channel Access (CAML) browser plugin,


download and run this script as root. The script works on RHEL5 and RHEL4 on x86 with EPICS R3-14-9 but has not been tested with other versions of EPICS. (The script overwrites existing EPICS environment variables, but only in the shell window where you run it.)

How to tell if the WebCA plug-in has installed on Linux:

Go to the browser's "Tools ... Add-ons ... Plugins" menu to see if "EPICS Channel Access Plug-In 1.2.0" is listed. Alternatively, check to see if libnpca.so has appeared in /usr/lib/mozilla/plugins. If these conditions are met, the plug-in is installed.

If you have installed the CAML plugin

and still don't see updating PVs, then most likely your EPICS environment variables are not properly set. (If you have run the plugin installation as root and started the browser as a regular user, then your EPICS environment variables won't be set.) Without root permissions, download this script, close your browser, and run as a regular user with the command "source resetCAMLepicsParameters.bash". Open a new browser from the shell window where you have run the script, not from a toolbar pulldown or a different shell window, and try viewing the page again.

Alternatively, close your browser, download an alternative script and use "source start_ARD_Web.bash" to open a new browser session that provides a view of all the ARD PVs.

Troubleshooting and Support

If you still can't get the CAML PV view to work, please report the following to Alison Chaiken:

  1. Operating system
  2. Browser, including version (pull-down menu Help . . . About Mozilla Firefox)
  3. Error message, if any from a shell window where you started the browser or from the Firefox Error Console (pull-down menu Tools ... Error Console)
  4. On Windows, check to see if the file npca.dll is present in c:\Program Files\Mozilla Firefox\plugins. On Linux, check to see if the file libnpca.so is present in /usr/lib/mozilla/plugins.
  5. Go to pull-down menu Tools . . . Add-ons . . . Plugins in the Firefox browser and see if the EPICS plug-in is installed
  6. On Windows, open Control Panel and choose System. Go to the Advanced tab and click the "Environment Variables" button. Please report the value of any variables with "EPICS" in the name. On Linux, type please report the result of typing set | grep EPICS at a bash shell.