In this section we study the 8255 chip. The 8255 is a 40 pin DIP chip. It has three
separately accessible ports. The ports are each 8 bit and are named A,B and C. The individual
ports of the 8255 can be programmed to be input or output and can be changed by dynamically.
In addition 8255 ports have handshaking capability, thereby allowing interface with devices
have handshaking, signal, such as printers.