diff options
Diffstat (limited to 'src/drivers/gps/ubx.cpp')
| -rw-r--r-- | src/drivers/gps/ubx.cpp | 58 |
1 files changed, 36 insertions, 22 deletions
diff --git a/src/drivers/gps/ubx.cpp b/src/drivers/gps/ubx.cpp index b0eb4ab66..e197059db 100644 --- a/src/drivers/gps/ubx.cpp +++ b/src/drivers/gps/ubx.cpp @@ -1,6 +1,6 @@ /**************************************************************************** * - * Copyright (c) 2012, 2013, 2014 PX4 Development Team. All rights reserved. + * Copyright (c) 2012-2015 PX4 Development Team. All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions @@ -748,17 +748,23 @@ UBX::payload_rx_done(void) timeinfo.tm_sec = _buf.payload_rx_nav_pvt.sec; time_t epoch = mktime(&timeinfo); -#ifndef CONFIG_RTC - //Since we lack a hardware RTC, set the system time clock based on GPS UTC - //TODO generalize this by moving into gps.cpp? - timespec ts; - ts.tv_sec = epoch; - ts.tv_nsec = _buf.payload_rx_nav_pvt.nano; - clock_settime(CLOCK_REALTIME, &ts); -#endif + if (epoch > GPS_EPOCH_SECS) { + // 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 = _buf.payload_rx_nav_pvt.nano; + if (clock_settime(CLOCK_REALTIME, &ts)) { + warn("failed setting clock"); + } - _gps_position->time_gps_usec = (uint64_t)epoch * 1000000; //TODO: test this - _gps_position->time_gps_usec += (uint64_t)(_buf.payload_rx_nav_pvt.nano * 1e-3f); + _gps_position->time_utc_usec = static_cast<uint64_t>(epoch) * 1000000ULL; + _gps_position->time_utc_usec += _buf.payload_rx_nav_timeutc.nano / 1000; + } else { + _gps_position->time_utc_usec = 0; + } } _gps_position->timestamp_time = hrt_absolute_time(); @@ -808,7 +814,7 @@ UBX::payload_rx_done(void) UBX_TRACE_RXMSG("Rx NAV-TIMEUTC\n"); { - /* convert to unix timestamp */ + // convert to unix timestamp struct tm timeinfo; timeinfo.tm_year = _buf.payload_rx_nav_timeutc.year - 1900; timeinfo.tm_mon = _buf.payload_rx_nav_timeutc.month - 1; @@ -818,17 +824,25 @@ UBX::payload_rx_done(void) timeinfo.tm_sec = _buf.payload_rx_nav_timeutc.sec; time_t epoch = mktime(&timeinfo); -#ifndef CONFIG_RTC - //Since we lack a hardware RTC, set the system time clock based on GPS UTC - //TODO generalize this by moving into gps.cpp? - timespec ts; - ts.tv_sec = epoch; - ts.tv_nsec = _buf.payload_rx_nav_timeutc.nano; - clock_settime(CLOCK_REALTIME, &ts); -#endif + // only set the time if it makes sense + + if (epoch > GPS_EPOCH_SECS) { + // 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 = _buf.payload_rx_nav_timeutc.nano; + if (clock_settime(CLOCK_REALTIME, &ts)) { + warn("failed setting clock"); + } - _gps_position->time_gps_usec = (uint64_t)epoch * 1000000; //TODO: test this - _gps_position->time_gps_usec += (uint64_t)(_buf.payload_rx_nav_timeutc.nano * 1e-3f); + _gps_position->time_utc_usec = static_cast<uint64_t>(epoch) * 1000000ULL; + _gps_position->time_utc_usec += _buf.payload_rx_nav_timeutc.nano / 1000; + } else { + _gps_position->time_utc_usec = 0; + } } _gps_position->timestamp_time = hrt_absolute_time(); |