[dox] some doxygen updates

sw/airborne/modules/cam_control/rotorcraft_cam.c

@@ -20,6 +20,23 @@
  * Boston, MA 02111-1307, USA.
  */
 
+/**
+ * @file modules/cam_control/rotorcraft_cam.c
+ * Camera control module for rotorcraft.
+ *
+ * The camera is controled by the heading of the vehicle for pan
+ * and can be controlled by a servo for tilt if defined.
+ *
+ * Four modes:
+ *  - NONE: no control
+ *  - MANUAL: the servo position is set with PWM
+ *  - HEADING: the servo position and the heading of the rotorcraft are set with angles
+ *  - WP: the camera is tracking a waypoint (Default: CAM)
+ *
+ * The CAM_SWITCH can be used to power the camera in normal modes
+ * and disable it when in NONE mode
+ */
+
 #include "modules/cam_control/rotorcraft_cam.h"
 
 #include "subsystems/actuators.h"

sw/airborne/modules/cam_control/rotorcraft_cam.h

@@ -20,7 +20,9 @@
  * Boston, MA 02111-1307, USA.
  */
 
-/** Camera control module for rotorcraft.
+/**
+ * @file modules/cam_control/rotorcraft_cam.h
+ * Camera control module for rotorcraft.
  *
  * The camera is controled by the heading of the vehicle for pan
  * and can be controlled by a servo for tilt if defined.

sw/airborne/subsystems/datalink/telemetry.h

@@ -29,21 +29,21 @@
  *
  * In order to use it a subsystem/module:
  * - include this header:
- *
+ *    @code
  *    #include "susystems/datalink/telemetry.h"
- *
+ *    @endcode
  * - write a callback function:
- *
+ *    @code
  *    void your_callback(void) {
  *      // your code to send a telemetry message goes here
  *    }
- *
+ *    @endcode
  * - register your callback function (if the message name doesn't match
  *   one of the names in your telemetry xml file or is already registered,
  *   the function return FALSE)
- *
+ *    @code
  *    register_periodic_telemetry(&your_telemetry_struct, "YOUR_MESSAGE_NAME", your_callback);
- *
+ *    @endcode
  * In most cases, the default telemetry structure should be used
  * (replace &your_telemetry_struct by DefaultPeriodic in the register function).
  */