I'd like the LCD show aaa=bbb, and show xxx=yyy for a while when the button pressed.
The code below works well, need help how to use mills replace the delay. Thanks.
#include <LiquidCrystal_I2C.h>
LiquidCrystal_I2C lcd(0x27, 2, 1, 0, 4, 5, 6, 7, 3, POSITIVE);
// constants won't change. They're used here to set pin numbers:
const int buttonPin = 2; // the number of the pushbutton pin
const int ledPin = 13; // the number of the LED pin
// variables will change:
int buttonState = 0; // variable for reading the pushbutton status
unsigned long interval5 = 5000; // the time we need to wait
unsigned long previousMillis5 = 0; // millis() returns an unsigned long.
unsigned long interval = 10000; // the time we need to wait
unsigned long previousMillis = 0; // millis() returns an unsigned long.
unsigned long currentMillis = millis(); // grab current time
void setup() {
Serial.begin(9600); // Used to type in characters
lcd.begin(16, 2); // initialize the lcd for 16 chars 2 lines, turn on backlight
//-------- Write characters on the display ------------------
// NOTE: Cursor Position: (CHAR, LINE) start at 0
lcd.setCursor(0, 0); //Start at character 4 on line 0
lcd.print("Hello, world!");
delay(20);
lcd.setCursor(0, 1);
lcd.print("testing");
//delay(5000);
// Set the PWM pins as output.
// initialize the LED pin as an output:
pinMode(ledPin, OUTPUT);
// initialize the pushbutton pin as an input:
pinMode(buttonPin, INPUT);
}
void loop() {
button();
test();
}
void button() {
// read the state of the pushbutton value:
buttonState = digitalRead(buttonPin);
// check if the pushbutton is pressed. If it is, the buttonState is HIGH:
// if (buttonState == HIGH) {
unsigned long currentMillis = millis();
if(currentMillis - previousMillis > interval) {
// save the last time you blinked the LED
previousMillis = currentMillis;
if (buttonState == HIGH) {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("xxx=");
lcd.print("yyy");
//delay(2000);
}
}
else {
// turn LED off:
digitalWrite(ledPin, LOW);
}
}
void test() {
lcd.clear();
lcd.setCursor(0, 0);
lcd.print("aaa=");
lcd.print("bbb");
delay(1000);
}