diff options
Diffstat (limited to 'src/drivers/gps/ashtech.cpp')
| -rw-r--r-- | src/drivers/gps/ashtech.cpp | 28 |
1 files changed, 23 insertions, 5 deletions
diff --git a/src/drivers/gps/ashtech.cpp b/src/drivers/gps/ashtech.cpp index a2e292de2..a50767c22 100644 --- a/src/drivers/gps/ashtech.cpp +++ b/src/drivers/gps/ashtech.cpp @@ -38,7 +38,7 @@ ASHTECH::~ASHTECH() int ASHTECH::handle_message(int len) { char * endp; - + if (len < 7) { return 0; } int uiCalcComma = 0; @@ -99,8 +99,26 @@ int ASHTECH::handle_message(int len) timeinfo.tm_sec = int(ashtech_sec); time_t epoch = mktime(&timeinfo); - _gps_position->time_gps_usec = (uint64_t)epoch * 1000000; //TODO: test this - _gps_position->time_gps_usec += (uint64_t)((ashtech_sec - int(ashtech_sec)) * 1e6); + if (epoch > GPS_EPOCH_SECS) { + uint64_t usecs = static_cast<uint64_t>((ashtech_sec - static_cast<uint64_t>(ashtech_sec))) * 1e6; + + // FMUv2+ boards have a hardware RTC, but GPS helps us to configure it + // and control its drift. Since we rely on the HRT for our monotonic + // clock, updating it from time to time is safe. + + timespec ts; + ts.tv_sec = epoch; + ts.tv_nsec = usecs * 1000; + if (clock_settime(CLOCK_REALTIME, &ts)) { + warn("failed setting clock"); + } + + _gps_position->time_utc_usec = static_cast<uint64_t>(epoch) * 1000000ULL; + _gps_position->time_utc_usec += usecs; + } else { + _gps_position->time_utc_usec = 0; + } + _gps_position->timestamp_time = hrt_absolute_time(); } @@ -611,8 +629,8 @@ void ASHTECH::decode_init(void) } -/* - * ashtech board configuration script +/* + * ashtech board configuration script */ const char comm[] = "$PASHS,POP,20\r\n"\ |