With Analog Keypad library , you can uses Analog Keypad or Multiple buttons easily with ONLY a single Arduino pin.
The below are example code for Analog Keypad. It is similar for multiple buttons.
/*
Created by ArduinoGetStarted.com
This example code is in the public domain
Tutorial page: https://arduinogetstarted.com/library/arduino-analog-keypad-example
This example reads the pressed key from analog keypad and prints it to Serial Monitor.
*/
#include <ezAnalogKeypad.h>
ezAnalogKeypad keypad(A0); // create ezAnalogKeypad object that attach to pin A0
void setup() {
Serial.begin(9600);
// MUST READ: You MUST run the calibration example, press key one-by-one to get the analog values
// The below values is just an example, your keypad's value may be different
keypad.setNoPressValue(0); // analog value when no key is pressed
keypad.registerKey('1', 100); // analog value when the key '1' is pressed
keypad.registerKey('2', 150); // analog value when the key '2' is pressed
keypad.registerKey('3', 200); // analog value when the key '3' is pressed
keypad.registerKey('4', 250); // analog value when the key '4' is pressed
keypad.registerKey('*', 450); // analog value when the key '*' is pressed
keypad.registerKey('0', 500); // analog value when the key '0' is pressed
keypad.registerKey('#', 550); // analog value when the key '#' is pressed
// ADD MORE IF YOUR KEYPAD HAS MORE
}
void loop() {
unsigned char key = keypad.getKey();
if (key) {
Serial.println(key);
}
}
You can see the library reference and more example code here: Analog Keypad
