It's not quite as simple as just putting the MO2 data in record messages and using the nativeNum: option to identify it because there are many cases where more that one Moxy sensor is used at a time and it's necessary to keep track of which sensor was worn where.
The Muscle Oxygen FIT Profile uses the device_info messages to support multiple sensors in the FIT file. However, ConnectIQ only supports Record, Lap, and Session messages. It doesn't support device_info messages. Further, many data display software packages are not designed to use device_info data to keep track of data from multiple sensors of the same type.
The linked document uses several strategies to support multiple sensors. Different display software packages may make use of one or more of these strategies.
- The sensors can be identified as the "1st MO2 Sensor" and "2nd MO2 Sensor" and so on based on their FieldId or device_index without using any device_info information.
- The device_info can be encoded as a Session Message. This can include the serial_number and sensor_position.
- The field_name string lists the serial_number and sensor_position
Interestingly, none of these 3 strategies are useful in Garmin Connect. It sure would be nice if they displayed the field_name string with the Record Data to give some way to communicate metadata like sensor number or where it was worn.
I would appreciate any feedback on this approach.
http://my.moxymonitor.com/hubfs/documents/MO2%20Data%20in%20FIT%20Files.docx
I plan to update our Moxy data fields to use this approach within the next week.