2.5 10-pin rear connector
This connector is used for updating the MCU firmware. See section 4.5 for more information.
2.6 Reset and safe boot buttons
The reset button on the front panel resets the unit.
The safe boot button is used to set the unit in safe boot mode. In this mode the receiver executes only
the minimal functionality, such as updating new firmware into the SQI flash. USB communication is
disabled while in safe boot mode.
To set the receiver in safe boot mode:
• Press and hold the BOOT button.
• Press the RST button.
• Release the RST button.
• Release the BOOT button.
To use UART in safe boot mode, a training sequence needs to be sent to the receiver. The training
sequence is a transmission of two bytes (0x55 0x55) at the baud rate of 9600. Wait for at least 100
milliseconds before the interface is ready to accept commands.
2.7 I2C/SPI slide switch
⚠
The switch must be kept at the I2C position to ensure correct operation of the device!
⚠
Contact u-blox technical support for assistance if required.
2.8 LED
On the front panel of the unit, a single blue LED may be configured to follow the receiver time pulse
signal. If there is no GNSS fix, the LED will be lit without flashing.
UBX-20029244 - R03
C1-Public
Device description
C102-F9R - User guide
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