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README.md

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+
+**Services:**  
+The ROS driver offers several ROS services which can be used to communicate with the sensor. Especially
+services for sensor parametrization are available. For example to list, get and set parameters. See the 
+services documentation [services.md](./docs/services.md) for more details and how to use these services.

docs/services.md

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+## ROS Services
+
+The ROS driver provides the following services. They use the sensor specific Pepperl+Fuchs scan data
+protocol (PFSDP) which is a simple command protocol using HTTP requests and responses. Please see the
+following detailed descriptions and examples to call these services. The examples are based on the
+assumption that the node name is pf_r2000.
+
+**List parameters**  
+The service pfsdp_list_parameters returns a list of all available global sensor parameters.
+```
+ros2 service call /pf_r2000/pfsdp_list_parameters pf_interfaces/srv/PfsdpListParameters
+```
+
+**Get parameter**  
+The service pfsdp_get_parameter reads the current value of one global sensor parameters.
+```
+ros2 service call /pf_r2000/pfsdp_get_parameter pf_interfaces/srv/PfsdpGetParameter '{name: user_tag}'
+```
+
+**Set parameter**  
+Using the service pfsdp_set_parameter the value of any write-accessible global sensor parameter can
+be changed.
+```
+ros2 service call /pf_r2000/pfsdp_set_parameter pf_interfaces/srv/PfsdpSetParameter '{name: user_tag, value: test123}'
+```
+
+**Reset parameter**  
+The service pfsdp_reset_parameter resets one global sensor parameter to the factory default value.
+```
+ros2 service call /pf_r2000/pfsdp_reset_parameter pf_interfaces/srv/PfsdpResetParameter '{name: user_tag}'
+```
+
+**List I/Q parameters**  
+The service pfsdp_list_iq_parameters is similar to the generic list parameters service but returns
+all parameters related to the switching input/output channels I/Qn.
+```
+ros2 service call /pf_r2000/pfsdp_list_iq_parameters pf_interfaces/srv/PfsdpListIqParameters
+```
+
+**Get I/Q parameter**  
+The service pfsdp_get_iq_parameter is similar to the generic pfsdp_get_parameter service but operates
+on parameters related to the switching input/output channels I/Qn. The service returns the current
+value of one parameter.
+```
+ros2 service call /pf_r2000/pfsdp_get_iq_parameter pf_interfaces/srv/PfsdpGetIqParameter '{name: iq2_polarity}'
+```
+
+**Set I/Q parameter**  
+The service pfsdp_set_iq_parameter is similar to the generic pfsdp_set_parameter service but operates
+on parameters related to the switching input/output channels I/Qn. Using the service pfsdp_set_iq_parameter
+the value of any write-accessible I/Q parameter can be modified.
+```
+ros2 service call /pf_r2000/pfsdp_set_iq_parameter pf_interfaces/srv/PfsdpSetIqParameter '{name: iq2_polarity, value: active_low}'
+```
+
+**Get protocol info**  
+The service pfsdp_get_protocol_info returns basic version information on the communication protocol.
+```
+ros2 service call /pf_r2000/pfsdp_get_protocol_info pf_interfaces/srv/PfsdpGetProtocolInfo
+```
+
+**Reboot device**  
+The service pfsdp_reboot_device triggers a soft reboot of the sensor firmware.
+```
+ros2 service call /pf_r2000/pfsdp_reboot_device pf_interfaces/srv/PfsdpRebootDevice
+```
+
+**Factory reset**  
+The service pfsdp_factory_reset performs a complete reset of all sensor settings to factory defaults
+and reboots the device.
+```
+ros2 service call /pf_r2000/pfsdp_factory_reset pf_interfaces/srv/PfsdpFactoryReset
+```