But at least the coders at Semtech/Cycleo were aware of that:
And each time an NAV-TIMEGPS UBX message has been received:
- get the concentrator timestamp (using lgw_get_trigcnt, mutex needed to protect access to the concentrator)
- get the GPS time contained in the UBX message (using lgw_gps_get)
- call the lgw_gps_sync function (use mutex to protect the time reference that should be a global shared variable).
Then, in other threads, you can simply used that continuously adjusted time reference to convert internal timestamps to GPS time (using lgw_cnt2gps) or the other way around (using lgw_gps2cnt). Inernal concentrator timestamp can also be converted to/from UTC time using lgw_cnt2utc/lgw_utc2cnt functions.