Programming 8-bit PIC Microcontrollers in C

2.6. PIC16 C Input and Output

• RS232 serial data

• Serial LCD

• Calculator and keypad

If an electronic gadget has a small alphanumeric LCD, the chances are that it is a microcontroller application. Smart card terminals, mobile phones, audio systems, coffee machines, and many other small systems use this display. The LCD we use here has a standard serial interface, and only one signal connection is needed. The signal format is RS232, a simple low-speed protocol that allows 1 byte or character code to be sent at a time. The data sequence also includes start and stop bits, and simple error checking can be applied if required. The PIC 16F877, in common with many microcontrollers, has a hardware RS232 port built in. Further details of RS232 are found ...