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The codec controller should only be run after the UCL HSI device driver has been loaded, and preferably after the data rate on the device driver and on the codec have been set to the correct values. The codec controller should be run by root, or should be made root setuid, as it attempts to renice itself to negative priority levels so that other processes on the machine do not cause synchronisation loss. The code can be run under a normal uid, but this is definitely not recommended. The user interface can be run by any user, and does not require special permissions. You can run it on the same machine as the codec controller, though it is designed so the user interface can reside on any machine with a suitable network connection to the codec controller.
As root, on the machine with the codec attached, run:
Nothing will happen, until a user interface connects.
On the machine your user interface is to reside on, run:
The interface should now connect to the codec controller, and the codec controller will open the codec device, and start reading and writing data.
The user interface is shown in figure 4.
If the interface has connected correct, the activity indicator will start flashing, alternately one half then the other half green. This indicates reads and writes from the codec. How fast it flashes depends on the data rate set, but it should not be more often that once a second. If it doesn't flash at all, probably the user interface has failed to connect to the codec controller. If it flashes many times a second, it is likely that the reading and/or writing LWPs have crashed, and the codec controller needs pressing. However, if you are connected to a codec controller over a network suffering considerable loss, the activity light will become very erratic, and will not be a good guide to anything.
First, you should set the to the same data rate as the device driver and the codec. When you have done this, the and lights should be both green. It may take a number of seconds to stabilise to this state. If it fails to stabilise, first check in the codec ``tip" or ``kermit" window that the Requested transmit rate and the RS449 interface rate are both set to the same as your . (You may have to press to stop the fast update messages appearing in the ``tip" window.) If you have all the data rates set correctly, it may be that the codec device did not open correctly, or the codec did not upgrade to your data rate correctly - in such cases press and wait for about 20 seconds.
When both and lights are green, the codec controller is ready to send and receive from other codecs.