Chapter 4: First Steps: The UART

The standard UART on the Raspberry Pi are pins 8 (GPIO14) and 10 (GPIO15). In their first alternate mode (ALT0), these become TXD0 and RXD0. TXD0 should be connected to the RX pin on the UART cable, and RXD0 to the TX pin.

The cable has the standard Raspberry Pi serial console color scheme: green is TX, white is RX, black is ground, and red is 5V/500mA. Note that the Raspberry Pi 4 won’t work with voltage input.