This article is the application of GPIO of PIC18F458 to operate the circuit of 8 LEDs arranged in the same position as the numbers shown in Figure 1 by using 8 LED to be rearranged and called 7-Segment that can be applied to display numbers and another number of characters. In addition, the experimental board has installed a 7-Segment of 4 digits, allowing you to write a program to control the display of 4 digits of data.