RAW_IMU/HIGHRES_IMU : Add id extension to support multiple IMU (mavli…

…nk#1200)

message_definitions/v1.0/common.xml

@@ -3853,7 +3853,7 @@
       <field type="int16_t" name="zmag" units="mgauss">Z Magnetic field</field>
     </message>
     <message id="27" name="RAW_IMU">
-      <description>The RAW IMU readings for the usual 9DOF sensor setup. This message should always contain the true raw values without any scaling to allow data capture and system debugging.</description>
+      <description>The RAW IMU readings for a 9DOF sensor, which is identified by the id (default IMU1). This message should always contain the true raw values without any scaling to allow data capture and system debugging.</description>
       <field type="uint64_t" name="time_usec" units="us">Timestamp (UNIX Epoch time or time since system boot). The receiving end can infer timestamp format (since 1.1.1970 or since system boot) by checking for the magnitude the number.</field>
       <field type="int16_t" name="xacc">X acceleration (raw)</field>
       <field type="int16_t" name="yacc">Y acceleration (raw)</field>
@@ -3864,6 +3864,8 @@
       <field type="int16_t" name="xmag">X Magnetic field (raw)</field>
       <field type="int16_t" name="ymag">Y Magnetic field (raw)</field>
       <field type="int16_t" name="zmag">Z Magnetic field (raw)</field>
+      <extensions/>
+      <field type="uint8_t" name="id">Id. Ids are numbered from 0 and map to IMUs numbered from 1 (e.g. IMU1 will have a message with id=0)</field>
     </message>
     <message id="28" name="RAW_PRESSURE">
       <description>The RAW pressure readings for the typical setup of one absolute pressure and one differential pressure sensor. The sensor values should be the raw, UNSCALED ADC values.</description>
@@ -4574,6 +4576,8 @@
       <field type="float" name="pressure_alt">Altitude calculated from pressure</field>
       <field type="float" name="temperature" units="degC">Temperature</field>
       <field type="uint16_t" name="fields_updated" display="bitmask">Bitmap for fields that have updated since last message, bit 0 = xacc, bit 12: temperature</field>
+      <extensions/>
+      <field type="uint8_t" name="id">Id. Ids are numbered from 0 and map to IMUs numbered from 1 (e.g. IMU1 will have a message with id=0)</field>
     </message>
     <message id="106" name="OPTICAL_FLOW_RAD">
       <description>Optical flow from an angular rate flow sensor (e.g. PX4FLOW or mouse sensor)</description>