i have many questions to ask about uart and usart. A. What is the difference? B. How do you send data through it? C. What is the setup need to use the serial port?

A. UART VS. USART Universal Asynchronous Reciever Transmitter / Universal Synchronous-Asynchronous Reciever Transmitter. Different protocols on a similar bus... One can talk both ways simultaneously the other can't. Google the terms for a better description.

B, and C, - Build the Temperature sensor program in the NK guide, it uses the serial port to send data to your PC. It's setup and use is described there.

Rick