janetsmith2000@yahoo.com
New Member
How does the 4x4 keypad work?
I know the 4x4 keypad is consist of a matrix of switch, but how do the microcontroller recognize with key is being pressed?
for example, B4 is connected to B0,B1, B2, and B3. When SW1 is pressed, B0 and B4 is closed, thus B4 is HI. However, when B4 is HI, how does it know that it is SW1, but not SW5 or SW9 is being pressed?
Thanks。
I know the 4x4 keypad is consist of a matrix of switch, but how do the microcontroller recognize with key is being pressed?
for example, B4 is connected to B0,B1, B2, and B3. When SW1 is pressed, B0 and B4 is closed, thus B4 is HI. However, when B4 is HI, how does it know that it is SW1, but not SW5 or SW9 is being pressed?
Thanks。