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+KNX cEMI Server 
+===============
+
+Implementation Notes
+--------------------
+* currently only implemented for KNX USB Data Interface (Tunnel) and not KNXnet/IP for now
+
+* basically provides a complete KNX device (TP or RF) that also has a USB interface built-in which can be used to program either the local device stack or 
+remote devices via the attached medium (TP or RF).
+  * tested with ETS 5.7.x
+  * tested with Net'N'Node
+  * **Be careful when using this with TP as your HW setup might not have a galvanic isolation between the KNX bus and USB!**
+    * An [USB isolator](https://www.olimex.com/Products/USB-Modules/USB-ISO/) might be the easiest option. Not tested!
+    * ToDo: How is this realized in commercial KNX USB Data Interfaces?
+
+* cEMI client address (e.g. ETS) is based on KNX physical address of the local device stack +1
+  * Example: local device: 1.2.10 -> cEMI client address: 1.2.11
+  * PropertyWrite commands to change the cEMI client address are only temporary until next device restart
+
+* requires a USB stack which properly work with USB HID and provides interrupt IN/OUT endpoints for KNX HID reports.
+  * normal Arduino USB device stack does NOT work as it is missing required functionality
+  * TinyUSB stack is used instead, therefore the Adafruit SAMD core with TinyUSB enabled is used as the Arduino core
+
+Development environment
+-----------------------
+* PlatformIO
+* Segger J-Link EDU
+* [GY-SAMD21 Board, compatible to Adafruit Feather M0](https://eckstein-shop.de/GY-SAMD21-Mini-Breakout-fuer-Arduino)
+