Update common-sonar-L04xMTW-GL04xMT.rst

common/source/docs/common-sonar-L04xMTW-GL04xMT.rst

@@ -1 +1,42 @@
+.. _common-sonar-L04xMTW-GL04xMT:
 
+=======================
+Sonar L04xMTW / GL04xMT  
+=======================
+
+The L04xMTW / GL04xMT is an echosounders (aka underwater sonar) with a 2 / 6 m range. More details can be found in the `datasheet <https://github.com/AlksSAV/Sonar-to-i2c-NMEA-/blob/main/L04xMTW%20%20GL04xMT%20datasheet.pdf>`__ 
+
+
+Supported sonar models:
+
+- L041MTW, GL041MT (max 6m range)
+- L042MTW, GL042MT (max 2m range)
+
+Recommended Hardware
+--------------------
+
+- L04xMTW / GL04xMT
+- Arduino nano
+
+The firmware file (sonar_to_nmea__SDDBT.ino) is located in this `repository <https://github.com/AlksSAV/Sonar-to-i2c-NMEA-/blob/main/sonar_to_nmea__SDDBT.ino>`__ 
+
+Connecting and Configuring
+--------------------------
+.. image:: ../../../images/Sonars nmea.png
+
+The L04xMTW / GL04xMT provides distance measurements using the NMEA protocol over serial at 115200 baud.
+
+The sensor can be connected to any available serial/uart port on the autopilot.  In the diagram below the first sensor is connected to SERIAL2.
+
+
+If the SERIAL2 is used then the following parameters should be set:
+
+-  :ref:`SERIAL2_PROTOCOL <SERIAL2_PROTOCOL>` = 9 (Lidar)
+-  :ref:`SERIAL2_BAUD <SERIAL2_BAUD>` = 115 (115200 baud)
+
+Then the following range finder related parameters should be set:
+
+-  :ref:`RNGFND1_TYPE <RNGFND1_TYPE>` = 17 (NMEA)
+-  :ref:`RNGFND1_MIN_CM <RNGFND1_MIN_CM>` = 5
+-  :ref:`RNGFND1_MAX_CM <RNGFND1_MAX_CM>` = 600 (i.e. 6m).  *This is the distance in centimeters that the rangefinder can reliably read.*
+-  :ref:`RNGFND1_ORIENT <RNGFND1_ORIENT>` = 25 (i.e. down) if mounted on a boat