This article describes how to use Skylark GNSS corrections with a Unicore Communications UM980 receiver. The procedure outlined in this document has been performed using a Unicore UM980 evaluation board. 

For more information about Skylark, visit the Skylark FAQ.


        Refer to Unicore for the latest firmware version and UPrecise software.

Setup Steps

Step 1: Check Receiver Firmware Version

1. Connect computer's RS232 serial port to COM1 port of the UM980 evaluation board. Null modem adapter is needed.

2. Connect the receiver to an antenna with an open sky view.

3. Power up UM980 board.

4. Start UPrecise program and connect to the receiver’s COM port and ensure communication is established.

5. In the Data Stream window, type unlogall and press Enter. All data displays will stop.

6. In the Data Stream window, type version and press Enter. System should respond with the receiver version:

7. Receiver firmware version is highlighted above. Ensure it’s at least R4.10 Build10561.

8. If the firmware version is not correct, follow the instructions in the UPrecise User Manual to upgrade your receiver.

9. In the Data Stream window, type reset and press Enter. After the board resets, all data should display again.

Step 2: Configure Receiver Settings

1. To operate with Skylark, receiver needs to output NMEA GGA messages. If GGA message is not being output enable it by typing log gpgga ontime 1 in the Data Stream window and press Enter.    

2. If required, other messages can be enabled in the same way. Examples:

log gprmc ontime 1

log gpgsv ontime 1

log gpgst ontime 1

3. To save settings type saveconfig in the Data Stream window and press Enter.

Step 3: Connect to Skylark

1. In UPrecise, go to menu Tools -> RTCM to open NTRIP client

NTRIP Client Window:

2. Click Input button on the RTCM Monitor to configure NTRIP Client

3. Set the NTRIP Caster Host to one of the following: for North America for Europe for Asia

4: Set Port to: 2101

5. Set Mount point to one of the following:

MSM5 for Skylark Cx

DGNSS-MSM1 for Skylark Dx

RTK-MSM5 for Skylark Nx RTK

6. Enter User ID and Password of your Skylark account

7. Set GGA Location reporting to 1 and check box

8. Select CurrentSerialGGA option

9. Click OK

10. Click Output on RTCM Monitor.

11. In the first row, select the same serial port and baud rate as the being used for communication with UM980 and enable it (check box)

12. Click OK

13. Click the Connect button on the RTCM Monitor.

Both Input and Output buttons should become green and data should show in the window. Correction stream is a binary data and is not humanly readable.

14. Close the RTCM Monitor window.

Step 4: Validate Operation

Watch the FixType field in the position status window in the Map view. It should change to RTK Float or RTK Fixed when the receiver uses Skylark corrections.

Related Articles

Receiver Configuration for Skylark Cx Operation

Receiver Configuration for Skylark Nx RTK Operation