USART Exported Constants

Modules
	USART Error Code
	USART Error Code.
	USART Word Length
	USART Number of Stop Bits
	USART Parity
	USART Mode
	USART Clock
	USART Clock Polarity
	USART Clock Phase
	USART Last Bit
	USART NACK State
	USART Flags
	Elements values convention: 0xXXXX.
	USART Interrupts Definition
	Elements values convention: 0xY000XXXX.