ArduPilot is configuring a newer u-blox GPS
What ArduPilot says:
- GPS N: updating GNSS mode
- GPS N: VALSET NACK, falling back to single key setting
- GPS N: u-blox fetching config
- GPS N: u-blox configured
- GPS N: u-blox identifying signals
Version 4.7 can configure u-blox receivers by reading and writing their settings as lists of keys and values. It does so when the receiver supports nothing else (protocol 40 and later), or when bit 8 of GPS_DRV_OPTIONS asks for it. The lines follow its steps: finding which satellite signals the module has (“identifying signals”), switching them to match GPSn_GNSS_MODE (“updating GNSS mode”), reading the settings (“fetching config”) and, once every setting matches, “u-blox configured”. “VALSET NACK, falling back to single key setting” means the module refused a batch of settings, and ArduPilot now sends them one at a time.
Until “u-blox configured” appears, arming is held back with “GPS 1 still configuring this GPS”. If it never appears, the module is refusing a setting: GPSn_GNSS_MODE asking for a signal it does not have is the usual one.
Parameters to look at
| Parameter | What it is |
|---|---|
GPS_DRV_OPTIONS | driver options |
GPS1_GNSS_MODE | GNSS system configuration |
GPS_AUTO_CONFIG | Automatic GPS configuration |
The code that sends it
GPS N: updating GNSS mode
libraries/AP_GPS/AP_GPS_UBLOX_CFGv2.cpp AP_GPS_UBLOX_CFGv2::_send_gnss_cfg() · Open in ArduPilot Copter-4.7.1
GPS N: VALSET NACK, falling back to single key setting
libraries/AP_GPS/AP_GPS_UBLOX_CFGv2.cpp AP_GPS_UBLOX_CFGv2::handle_cfg_nack() · Open in ArduPilot Copter-4.7.1
GPS N: u-blox fetching config
libraries/AP_GPS/AP_GPS_UBLOX_CFGv2.cpp AP_GPS_UBLOX_CFGv2::update() · Open in ArduPilot Copter-4.7.1
GPS N: u-blox configured
libraries/AP_GPS/AP_GPS_UBLOX_CFGv2.cpp AP_GPS_UBLOX_CFGv2::process_valget_complete() · Open in ArduPilot Copter-4.7.1
And 1 more messages, sent from the same places.