How To Send RS-232 Serial Data using a MAX-232 or direct connection

This application note covers transmission of asynchronous serial data using PICmicro® microcontrollers. It presents an example program in TechTools assembly language that transmits a text string serially via RS-232 at speeds up to 19,200 bits per second. Hardware examples demonstrate the use of a popular serial line driver, as well as a method for using the PICmicro® MCU's output to directly drive a serial line.