Component knowledge
7-segment display
7-segment display is a digital electronic display device. There is a figure of "8" and a decimal point, which
consist of 8 LED. According to the difference about common cathode and anode. its internal structure and
pins diagram is shown below:
As is known from the above circuit diagram that we can control the state of each LED separately. So, through
combining LED with different state, we can display different numbers. For example, display figure 0: we need
to turn on LED segment A, B, C, D, E, F, and turn off LED segment G and DP.
In this project, we use a display 7-segment (common anode). Therefore, when the input low level to a LED
segment, the LED will be turned on. Define segment “A” as the lowest level, the segment “DP” as the highest
level, that is, from high to low: “DP”, “G”, “F”, “E”, “D”, “C”, “B”, “A”. And character "0" corresponds to the code:
1100 0000b=0xc0.