# GNSS functions

To access the GNSS functions screen, tap the receiver icon in the status bar.

Use the GNSS functions screen to control commonly-used functions for the connected GNSS receiver, such as switching Bluetooth connections between the configured base and rover receivers, starting or ending the survey, or powering down the receiver. The GNSS functions screen also provides fast access to detailed information including receiver status, position details, and available satellites.

The functions available depend on the receiver that the controller is connected to, and the mode the receiver is operating in. A yellow button indicates the function is enabled.

When in the GNSS functions screen, you can use the controller keypad to enter the keypad character (1–9, 0, - or .) indicated on the tile to enable/disable the function or open the appropriate screen. If you have configured a function key on the controller as a shortcut to a GNSS function, you can press the configured function key when viewing any screen in the software.

Base mode

When Base mode is enabled, when you start the software Trimble Access attempts to connect to the receiver configured in the Connect to GNSS base field in the Bluetooth tab of the Connections screen. The receiver icon in the status bar indicates if the software is in Base mode.

If there is no receiver configured, the software checks if there is a receiver connected to the controller's serial port. When the software is in Base mode, if a receiver is found on the serial port it is treated as the base receiver.

In Base mode the Start survey and End survey buttons in GNSS functions start or end a base survey using the current survey style.

Rover mode

When Rover mode is enabled, when you start the software Trimble Access attempts to connect to the receiver configured in the Connect to GNSS rover field in the Bluetooth tab of the Connections screen. The receiver icon in the status bar shows if the software is in Rover mode.

If there is no receiver configured, the software checks if there is a receiver connected to the controller's serial port. When the software is in Rover mode, if a receiver is found on the serial port it is treated as the rover receiver.

In Rover mode the Start survey and End survey buttons in GNSS functions start or end a rover survey using the current survey style.

Bluetooth

Tap Bluetooth to view the Bluetooth tab of the Connections screen and configure separate Bluetooth connections to the base and rover receivers. Then use the Base mode and Rover mode buttons in the GNSS functions screen to switch between and connect to the receivers.

Data link

You can tap the Data link button to connect to and configure the radio you are using for your RTK data link.

When the instrument is in Rover mode, tap Data link to go to the Rover data link settings screen.

When the instrument is in Base mode, tap Data link to go to the Base data link settings screen.

If the softkey displays >Rover or >Base tap the softkey to switch to the appropriate mode and then tap Connect.

If there is an RTK survey running, the radio screen shows the radio currently in use, and you may not be able to connect to an external radio.

When a survey is not running, you can select the type of RTK radio you are using and then tap Connect (if it is available) to connect to and configure the communication settings in the radio. You can review and set the radio frequency, baud rate, and other settings if they are available to change in the radio device that the instrument is connected to. See Configuring a radio data link.

You cannot edit survey style settings in this screen. If you start a survey with a different type of radio set in the survey style, the system uses that radio – not the radio that you set in GNSS functions.

Start survey, end survey, power down receiver

To start a GNSS survey, tap Start survey.

To end the survey, tap End survey. You are prompted to power down the receiver. Tap Yes or No, as required.

To power down the receiver after ending a survey, tap Power down receiver.

Satellites

To view information about the satellites being tracked, tap Satellites. See Satellite information.

Position

To view and store the current position, tap Position. See Current position information.

Navigate to point

To navigate to a point, tap Navigate to a point. See Navigate to a point.

IMU tilt compensation

This button is shown only if the connected receiver has an inertial measurement unit (IMU).

To disable IMU tilt compensation and switch to using GNSS-only mode during a survey, for example when using a bipod in heavy canopy and the receiver needs to remain stationary for a period., tap IMU tilt compensation. In good RTK environments where movement is happening constantly, tap IMU tilt compensation to re-enable it. See IMU tilt compensation.

Import from receiver and export to receiver

To import files from or export files to the receiver, tap Import from receiver or Export to receiver. See Transfer receiver files.

This button is not shown if the IMU tilt compensation button is shown.

Receiver status

To view the status of the receiver, tap Receiver status. See Receiver status.