SAFEBOOT_N1D_SEL2TIMEPULSE3EXTINT4USB_DM5USB_DP6V_USB7RESET_N8VCC_RF9GND10RF_IN11GND12GND13LNA_EN14Reserved15Reserved16Reserved17SDA/SPCS_N18SCL/SPI-SLK19TXD/SPI-MISO20RXD/SPI-MOSI21V_BCKP22VCC23GND24