Registers for serial communication.
sets theg communication speed and other settings.
ends the serial communication and sets RX and TX pins to normal input/output mode.
reads data from receive buffer.
reads data from receive buffer without modifying the buffer.
returns how many bytes can be written to receive buffer of serial communication.
sends all data in the serial transmit buffer.
wites binary data to serial port.
returns how many bytes can be written to transmit buffer of serial communication.
copies data from Arduino serial communication transmit buffer to ATmega328P data transmit register.