diff --git a/doc/mqtt.md b/doc/mqtt.md
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+# mqtt interface
+
+The mqtt interface serves two purposes.
+* Data is made available at regular intervals.
+* Defined commands can be sent to the device.
+
+Every topic starts as subtopic of **ebus/**
+
+These topics are available on every device.
+|***topic***          |***description***
+|:-                   |:-
+|**device**           |
+|ebus/device          |information about your device                                   
+|ebus/device/ebus     |basic ebus adapter settings (Configration)
+|ebus/device/firmware |details of installed firmware
+|ebus/device/wifi     |wifi details
+|**counter**          | 
+|ebus/arbitration     |arbitration over common interface 
+|ebus/arbitration/won |details of won arbitration 
+|ebus/arbitration/lost|details of lost arbitration     
+|**commands**         |
+|ebus/config/restart  |restarting of the device 
+|-                    |
+|**EBUS_INTERNAL=1**  |
+|**output**           |
+|ebus/commands        |list of installed commands
+|ebus/value           |received values of installed commands
+|ebus/system          |time and outdoor temperature of system (Service 07h 00h)
+|ebus/nodes           |decoded answer from an active sent identification telegram (Service 07h 04h)
+|ebus/sent            |values of 'send' command: subtopic=master; value=slave;
+|ebus/raw             |values of 'raw' printout: subtopic=master; value=slave;
+|**counter**          |
+|ebus/messages        |processed messages
+|ebus/errors          |errors of finite state machine  
+|ebus/resets          |resets of finite state machine 
+|ebus/requets         |bus requests (arbitration)
+|**commands**         |
+|ebus/config/insert   |insert new command
+|ebus/config/remove   |remove loaded command
+|ebus/config/list     |list loaded commands
+|ebus/config/load     |loading saved commands
+|ebus/config/save     |saving loaded commands
+|ebus/config/wipe     |wiping saved commands
+|ebus/config/send     |sending of given ebus command(s) once
+|ebus/config/raw      |enable/disable of raw data printout
+|ebus/config/filter   |filter for raw data printout
+|**response**         |
+|ebus/config/loading  |bytes of loaded commands
+|ebus/config/saving   |bytes of saved commands
+|ebus/config/wiping   |bytes of wiped commands
+|ebus/conifg/error    |message of last occurred error
+
diff --git a/doc/mqtt.txt b/doc/mqtt.txt
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index 0000000..69c3197
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+++ b/doc/mqtt.txt
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+# mqtt interface
+
+The mqtt interface serves two purposes.
+* Data is made available at regular intervals.
+* Defined commands can be sent to the device.
+
+Every topic starts as subtopic of **ebus/**
+
+These topics are available on every device.
+|***topic***          |***description***
+|:-                   |:-
+|**device**           |
+|ebus/device          |information about your device                                   
+|ebus/device/ebus     |basic ebus adapter settings (Configration)
+|ebus/device/firmware |details of installed firmware
+|ebus/device/wifi     |wifi details
+|**counter**          | 
+|ebus/arbitration     |arbitration over common interface 
+|ebus/arbitration/won |details of won arbitration 
+|ebus/arbitration/lost|details of lost arbitration     
+|**commands**         |
+|ebus/config/restart  |restarting of the device 
+|-                    |
+|**EBUS_INTERNAL=1**  |
+|**output**           |
+|ebus/commands        |list of installed commands
+|ebus/value           |received values of installed commands
+|ebus/system          |time and outdoor temperature of system (Service 07h 00h)
+|ebus/nodes           |decoded answer from an active sent identification telegram (Service 07h 04h)
+|ebus/sent            |values of 'send' command: subtopic=master; value=slave;
+|ebus/raw             |values of 'raw' printout: subtopic=master; value=slave;
+|**counter**          |
+|ebus/messages        |processed messages
+|ebus/errors          |errors of finite state machine  
+|ebus/resets          |resets of finite state machine 
+|ebus/requets         |bus requests (arbitration)
+|**commands**         |
+|ebus/config/insert   |insert new command
+|ebus/config/remove   |remove loaded command
+|ebus/config/list     |list loaded commands
+|ebus/config/load     |loading saved commands
+|ebus/config/save     |saving loaded commands
+|ebus/config/wipe     |wiping saved commands
+|ebus/config/send     |sending of given ebus command(s) once
+|ebus/config/raw      |enable/disable of raw data printout
+|ebus/config/filter   |filter for raw data printout
+|**response**         |
+|ebus/config/loading  |bytes of loaded commands
+|ebus/config/saving   |bytes of saved commands
+|ebus/config/wiping   |bytes of wiped commands
+|ebus/conifg/error    |message of last occurred error
+