hi i am doing a project where i have to read a 2 byte hex code from a Card reader , in an external ROM create a table with every code corresponding to a num , once the code is read extract the corresponding num and display it . i am using 8255 and using 2 of its ports to read the code and one port to connect to a display unit having 5 seven segment displays . is this the most efficient way for this application . i am a amature in this field and am finding the programming part a bit difficult