Setup & Getting Started (PX4)

Connection to Autopilot

Various JST-GH cables are provided to attach to the UM982 10 pin JST-GH connector. Two are full 10 wire cables (short and long) for connecting to Pixhawk Standard Autopilot’s GPS1 connector, or similar, and provide full functionality including safety switch button and LED.
The 10Pin - 6Pin cable allows users to connect the UM982 to GPS2 port on Cubepilot and Holybro Autopilots.
The module can be used with one antenna or both antennas. If it is used with one antenna only, the right/primary antenna connector needs to be connected.

PX4 Configuration

Port Setup

The Unicore module talks the NMEA protocol extended with some proprietary Unicore sentences. The serial baudrate is 230400.
The following PX4 parameters must be set:
Note, the above parameters assume you are connected to GPS 1. If you are using another port you will have to use its parameters to configure the baud rate and protocol.

Enable GPS Heading/Yaw

The Unicore module comes with two antennas, a primary (right connector) and a secondary (left connector) antenna, which can be used to get yaw from GPS. You will need to set the following parameters:
  • EKF2_GPS_CTRL: Set bit 3 (8) to enable dual antenna heading into the yaw estimation.
  • GPS_YAW_OFFSET: Set heading offset to 0 if the primary antenna is in the front. The angle increases clock-wise, so set the offset to 90 degrees if the primary(master) antenna is on the right side of the vehicle, and the secondary(slave) on the left side.

RTK Corrections

RTK works the same way as uBlox F9P modules. RTCMv3 corrections as sent by QGroundControl from an RTK GPS base station are consumed by the Unicore module, which should then change fix type to RTK float or RTK fixed.

Advanced Application

For guide on Advanced application with Unicore Uprecise Software, please see link below.