Before moving ahead, let us discuss the widely used stuff for embedded designs for communication
ASCII stands for American Standard Code for Information Interchange. As computers or any digital systems can understand only numbers, ASCII code is introduced to communicate with digital system. ASCII code represents the numerical value of printable and non-printable characters.
ASCII ranges from 0 to 255 in Decimal. ASCII codes can be divided into two sets - Standard ASCII codes and Extended ASCII codes. Standard ASCII characters ranges from 0 to 127, where 0 to 31 are non-printable characters and above that are printable characters like '0' to '9', 'a' to 'b' and A to 'Z'. Extended ASCII codes range from 128 to 255. They meet the demand for more characters and symbols for communications.
Together, Standard ASCII table & Extended ASCII codes are widely used in communication protocol, such as RS-232, RS-485, RS-422 and TTL systems.
Serial port & Parallel Port
Communication ports plays the most important role in any Development of Embedded System for Programming and Communication. Serial port is extensively used for communication between Embedded hardware and System Application. Parallel port is also used for communication, but mostly it is used for programming or debugging. We will discuss these communication ports in depth with a new post.