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+## Protocol
+
+Every communication in either direction is prefixed with at most one byte indicating the kind of action/result.
+
+### from ebusd to device
+ * initialization (after connect)  
+   `<INIT>`  
+   This is not yet implemented in ebusd and supposed to be enhanced by another byte requesting certain features.
+ * send request  
+   `<SEND> <symbol>`  
+   Requests the specified symbol to be sent to the eBUS.
+ * arbitration start request  
+   `<START> <master address>`  
+   Requests the start of the arbitration process with the specified master address after the next received `<SYN>` symbol.
+
+### from device to ebusd
+  * initialization (after re-connect)  
+    `<RESETTED>`  
+    Indicates a reboot or an initial ebusd connection on the device.  
+    This is actually desired to be enhanced by another byte in future indicating availability of certain features (like full message sending instead of arbitration onnly).
+  * symbol received from eBUS  
+    `<RECEIVED> <symbol>`  
+    Indicates that the specified symbol was received from the eBUS.
+  * arbitration start succeeded  
+    `<STARTED>`  
+    Indicates that the last arbitration request was successful (arbitration was won).
+  * arbitration start failed  
+    `<FAILED>`  
+    Indicates that the last arbitration request failed (arbitration was lost or sending failed).
+
+
+## Symbols
+
+These are the predefined symbols as used above.
+
+### Generic
+ * SYN 0xAA
+
+### From ebusd to device
+ * INIT 0x00
+ * SEND 0x01
+ * START 0x02
+
+### From device to ebusd
+ * RESETTED 0x00
+ * RECEIVED 0x01
+ * STARTED 0x02
+ * FAILED 0x82
+
+