Plugged it into my laptop via the USB-C port and the blue and red LEDs are lit. It continually tried to connect so I read the web page and saw that I needed a driver. Downloaded and installed it, but it still tries to connect continuously. as before. I’d have thought that it should now connect although I haven’t proceeded with the additional eMMC firmware installation.
First, follow this official guide: get a bootable image, write it to a TF card, insert the card, check the position of the core switch, and connect the board to your computer with a USB data cable.
If it doesn’t help, try connecting a serial debug line to Duo S and reading what the SoC says while booting.