As shown in the figure, why use so many diodes for this matrix button?
Joanne postato su July 7, 2020
The transistor is often used as an input element. In the keyboard input, the diode is connected to different row buses and different column buses. The circuit scans the state of the logical combination of the keys on the keyboard at any time, such as what key is pressed at the same time, and it is better to execute .
Kenyon postato su July 7, 2020
What is the anode of D37 connected to? GND or what?
Elmer postato su July 7, 2020
Simultaneously pull down the two ports to make a difference and reuse the ports.