Introduce .

This function allows users to collect NMEA/RTCM/RAW data of RTK receivers via Bluetooth Classic / Bluetooth Low Energy (BLE ) while ESPrtk is running.

This function is similar to Bluetooth to Serial., but only one-way transmission from ESPrtk.  (  Only send data from RTK receivers to Bluetooth device ).

There are no exceptions to the type of NMEA/RTCM/RAW data, all of which are received and sent.

ESPrtk logo

It also supports sending real-time IMU data to Bluetooth device.

New feature :

Besides, the Bluetooth device can also act as a HOST and send control commands to ESPrtk in the same way as using on the RX / TX UART_0 port.

(HOST can send command PING, GPIO control command, check ESPrtk current system error, send restart command or control ESPrtk switch to UART / WEB Configure mode, ..... ESPrtk will respond ACK data / NACK back to HOST over Bluetooth connection).

BLE Viewer on NTRIP Rover - MQTT Rover - Radio RTK Rover.

Send NMEA-RTCM-RAW/.. Data (from RX-UART-RTK) to Bluetooth Client

After restarting (power on or Reset), ESPrtk works as usual (receives RTCM from Base and stream out to TX-B (TX_UART1 or TX_UART2)), and collects all NMEA data from RX-A port (RX_UART1 or RX_UART2)  and sends it to Bluetooth Client device.

ESPrtk logo

BLE Viewer on NTRIP Base - MQTT Base - Radio RTK Base.

Send NMEA-RTCM-RAW/.. Data (from RX-UART-RTK) to Bluetooth Client

After restarting (power on or Reset), ESPrtk works as usual (receives RTCM/RAW from RX_UART-RTK (RX_UART1 or RX_UART2) and send to Server), and collects all RTCM/RAW data from RX_UART-RTK   and sends it to Bluetooth Client device.

ESPrtk logo

To use it.

Now, just open your app , open Bluetooth and connect to ESPrtk to get data from GPS module. 

During the operation, if Bluetooth Client disconnects the connection, ESPrtk will not report an error and the Bluetooth Client will be able to reconnect.
Sometimes reconnection needs patience and wait to connect successfully.

Bluetooth Classic and Bluetooth Low Energy

Bluetooth Classic: Basic bluetooth mode supported by most devices.

Bluetooth Low Energy: Bluetooth mode is recommended to use, it is stable, energy-saving, high enough for RTK applications.


ESPrtk logo

GNSS Surveyor – Android application.

Here is the full Introduction for “GNSS Surveyor ” on google play store :

Connect external Bluetooth GNSS device with GNSS Surveyor and compare your location with different satellite systems. It provides advanced GNSS information such as HRMS, VRMS, 3DRMS values, HDOP, PDOP, VDOP, Differential Status, Satellites In View and Used, which are important for GIS and Surveying data collection.
Easy to allow mock location on your android phone or tablet and use the position of the external receiver in any 3rd party application. Get GPS status data like position, height, accuracy, satellites, speed in real time. View and analyse the position data provided by the GNSS receivers and metadata related to its location.

* Compatible with Android OS 4.0.3 and newer.
* Designed and developed to work with Bluetooth 2.x.

* Display location information and quality of the position data in real-time with sub-meter/ centimeter accuracy.
* View all or Hide all constellations individually on skyplot and distinct colour for different constellations for better identification.
* Constellation information for GPS, GLONASS, GALILEO, BEIDOU, QZSS, SBAS.
* Send commands to external GNSS GPS device and view the output data on Terminal.
* Log all received NMEA Messages and Binary Data on Terminal window.
* Easy to use one touch previously configured commands to communicate directly with GNSS Bluetooth device.
* Record and transfer the raw data file allowing post-processing of information for surveying and forestry, utilities, agriculture, environmental and other natural resource industry professionals.
* Built-in NTRIP client to access RTK or DGNSS correction from any RTK Network.
* Direct IP feature for RTK corrections data.
* Configurable audible and visual alerts.
* Multi language support.
* Multi measurement units support.
* Convert DMS to DD or vice versa.

Technical Support:-
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