missed setting up routing for the analog pin..

board.c

@@ -197,6 +197,10 @@ void BoardInitMcu( void )
 
     AdcInit( &Adc, PB_15 );  // Just initialize ADC
 
+	/* setup routing */
+	__HAL_RI_IOSWITCH_CLOSE(RI_IOSWITCH_CH21);
+	__HAL_RI_SWITCHCONTROLMODE_ENABLE();
+
 #if defined( SX1261MBXBAS ) || defined( SX1262MBXCAS ) || defined( SX1262MBXDAS )
     SpiInit( &SX126x.Spi, SPI_1, RADIO_MOSI, RADIO_MISO, RADIO_SCLK, NC );
     SX126xIoInit( );