UART
The Grove UART port connect to the GPIO14(UART0 TX) and GPIO15(UART0 RX). UART is commonly used on the Pi as a convenient way
to control it over the GPIO, or access the kernel boot messages from the serial console (enabled by default).It can also be used as a way to
interface an Arduino, bootloaded ATmega, ESP8266, etc with your Pi.
Digital
There are 6 digital Grove sockets in this board, normally the yellow wire(which connect to the top pin of the 4 pins Grove socket as) of Grove
cable is the signal wire, so we name the digital Grove port
D5/D16/D18/D22/D24/D26
.
