Another experiments from Embedded Lab. In this experiment, the author tries to explain how someone can interface the classic seven segment LED displays on a PIC microcontroller. He makes a counter that counts form 0 to 15, and the hexadecimal value (0x0 to 0xF) is displayed on a 7-seg display. The microcontroller he chose again is the PIC 16F688, and the display is common cathode.
Follow this link to see this well-documented entry.