Maker: Radxa

• You may flash an OS image directly to the Rock S0 internal EMMC flash as follows:
  • Build Linux x86 binary rkdeveloptool (sources) on host
  • Remove any SDcard
  • Hold down the tiny, black MASKROM button while you…
  • Power on, with the MASKROM button pressed, to enter flash mode
  • Release the MASKROM button after 2 seconds
  • Next, run these host commands to flash the internal EMMC flash:
    • • sudo rkdeveloptool db rk3308_loader_uart0_m0_emmc_port_support_sd_20190717.bin
      • #await output: Downloading bootloader succeeded.
      • sudo rkdeveloptool wl 0 /path/to/uncompressed_armbian_image
      • #await output: Write LBA from file (100%)
      • sudo rkdeveloptool rd
      • #outputs: Reset Device OK.
        (check official step by step instructions)

     

• If a valid image is found on the built-in EMMC flash, the board will boot that image unless…
• Holding down the MASKROM button disables the EMMC flash.
• If no valid image can be read from EMMC flash, it will attempt to boot from SD Card.
• The white “RECOVERY” button as no predefined function.
• The Rock S0 has no “reset” button!
• Kernel serial console is on UART0.
• The serial console operates at 1.5Mbaud with 8 data, 1 stop, and no parity bits.
  
• Red(far right)=+5V, Black(center right)=GND,White(center left)=TxD, Green(far left)=RxD

There is no need to attach the +5V to the GPIO header (as pictured above) if the board is powered via USB.

If not using an external antenna, consider adding this line to /boot/armbianEnv.txt file to increase CPU clock to 1.3 GHz:

overlays=b@1.3ghz

However, use of an external antenna will dramatically improve radio performance.

If using an external antenna, consider adding this line to /boot/armbianEnv.txt file to increase CPU clock to 1.3 GHz and select the external antenna:

overlays=b@1.3ghz s0-ext-antenna

Refer to /boot/dtb/rockchip/overlay/README.rockchip-overlays for more information.