Native Code
If you are most comfortable writting in C or C++ then you should look at:
Native Sensor Device API
A vendor would need to implement all the functions that start with SensDev_
Java Code
If you are more comftable with Java then you should look at the javadocs. These are still sparsely commented, but they should give you some idea.
One way to write a java sensor device is to extend the AbstractSensorDevice class http://xeon.concord.org/workspaces/docs/Sensor/org/concord/sensor/device/AbstractSensorDevice.html
In this case you would implement all the abstract methods.
Another way is to extend the AbstractJavaSensorDevice class. This should take care of several of the things you would have to do if you just extend AbstractSensorDevice.
The Java Code is not documented very well at this point. The best documentation is on the following pages:
http://xeon.concord.org/workspaces/docs/Sensor/org/concord/sensor/SensorConfig.html
http://xeon.concord.org/workspaces/docs/Sensor/org/concord/sensor/SensorRequest.html
