This is the same UART0 port, but with the big one, you can use 5V in/out (in “in” mode ONLY if the Blade has no other power source)
Connect “correctly”:
- RX -> TX
- TX -> RX
- GND -> GND
in config:
enable_uart=1
You can change the bootloader setting to enable UART from the boot. Add this line to boot.conf and flash the bootloader:
BOOT_UART=1
Follow this link to the Raspberry Pi Documentation BOOT_UART value