Art, in this example there is a multiplexed 7-segment LCD, 4 commons, display that I am running directly from the PIC. The advantage of the 4 commons is that you only need one pin in the PIC for every 4 segments of the display, so you minimize the number of needed pins.

The byte PATTERN changes its value for everyone of the 8 digits of the display. After enabling the LCD feature in the PIC, you need to load LCDDATA the registers for it to work.