Each key on the keyboard can input various numbers and symbols, which also integrated a microphone. You can use it for scenarios such as phone buttons. Add a lot of fun to your project.
Connect a number of lower resistors through an upper resistor. These lower resistors are not directly grounded, but each resistor is connected in series with a light touch button. The resistance of each lower resistor is different, according to Ohm's law, each time you press a different key, you will get different voltage values between the upper and lower resistors. Send these voltage values to the controller, and then calculate and encode these different voltage values. The codes correspond to various numbers and symbols, so that various numbers and symbols can be obtained through the key panel.
The meaning of each key on the silicone keyboard can be determined through the program, which can be letters or symbols, and a series of information can be entered by pressing different keys.