# Precompiled device trees: Each folder contains a `.dtb` file, which is the compiled device tree itself, plus a `.dts` with the original source and a `.gpio` file showing the GPIO pin mappings. ## Generic [./generic](The generic device tree I will use in my project, suitable for many occasions) * Has 2x UART (plus the console uart), 2x I2C. 1xSPI * 12 unassigned GPIO pins ## Serial [./serial](Four UART interfaces *and* Four I2C interfaces) * Has 4x UART (plus the console uart), 4x I2C * UART3 has RTC/CTS pins available too * 10 unassigned GPIO pins ## SPI [./spi](SPI plus Serial interfaces) * Has 3x UART (plus the console uart), 3x I2C. 1xSPI * 8 unassigned GPIO pins ## SunXI [./sunxi](Vanilla, unpopulated, upstream) * Has the console uart, nothing more * *26 unassigned GPIO pins!* ## AllWinner Nezha [./allwinner-nezha](DO NOT USE) * Included for completeness, this is the default device tree you get with the Ubuntu image. * Has the console uart, 1x I2C. 1xSPI * 15 unassigned GPIO pins, 3 pre-assigned to pinctl