W tym poście pokazuję jak połączyć wyświetlacz LCD z Arduino korzystając z magistrali I2C. Dzięki temu do komunikacji użyte są tylko dwa piny plus zasilanie.
Pomaga nam w tym ekspander PCF8574P.
Oto schemat połączeń dla Arduino Uno R3:
Uwaga! Ja korzystam z Arduino Uno R3 i ma on wyprowadzone dodatkowo piny magistrali I2C tak jak na rysunku powyżej. Równie dobrze można z ekspandera wyjść na piny A4 i A5, jak w tabelce.
Łączenie z innymi platformami:
| Arduino boards | I2C / TWI pins |
| Uno, Ethernet | A4 (SDA), A5 (SCL) |
| Mega2560 | 20 (SDA), 21 (SCL) |
| Leonardo | 2 (SDA), 3 (SCL) |
| Due | 20 (SDA), 21 (SCL), SDA1, SCL1 |
Potrzebne części:
Potencjometr 10k.
Expander PCF8574P
Arduino Uno R3
Biblioteki do instalacji:
https://github.com/fdebrabander/Arduino-LiquidCrystal-I2C-library.git
Kod 1:
#include //Standardowa biblioteka Arduino
#include
LiquidCrystal_I2C lcd(0x16,16,2);
void setup()
{
lcd.init();
lcd.print("Hello, world!");
}
void loop()
{
}
Kod 2:
#include
#include
LiquidCrystal_I2C lcd(0x16,16,2);
void setup()
{
lcd.init();
lcd.backlight();
Serial.begin(9600);
}
void loop()
{
if (Serial.available()) {
delay(100);
lcd.clear();
while (Serial.available() > 0) {
lcd.write(Serial.read());
}
}
}
Kod 3:
#include
#include
LiquidCrystal_I2C lcd(0x20,16,2); // set the LCD address to 0x20 for a 16 chars and 2 line display
int time = 0;
void setup()
{
lcd.init();
lcd.backlight();
lcd.setCursor(0, 0);
lcd.print("3w.yarogniew.net");
}
void loop(){
//Przejście kursora do pierwszej kolumny drugiego wiersza
lcd.setCursor(2, 1);
//Odczyt oraz wyświetlenie czasu jaki upłynął od ostatniego resetu w sekundach
time = millis()/1000;
lcd.print("time:");
lcd.print(time);
///lcd.print("---");
/*if (time==10){
lcd.noDisplay();
lcd.setCursor(5, 1);
lcd.print("czas=20");
delay(3000); // czekaj
lcd.display();
lcd.setCursor(5, 1);
lcd.print(" ");
}
*/
}
Kod 4:
/*
DS3231_test.pde
Eric Ayars
4/11
Test/demo of read routines for a DS3231 RTC.
Turn on the serial monitor after loading this to check if things are
working as they should.
*/
#include
#include
#include
LiquidCrystal_I2C lcd(0x20,16,2); // set the LCD address to 0x20 for a 16 chars and 2 line display
int time = 0;
DS3231 Clock;
bool Century=false;
bool h12;
bool PM;
byte ADay, AHour, AMinute, ASecond, ABits;
bool ADy, A12h, Apm;
byte year, month, date, DoW, hour, minute, second;
void setup() {
// Start the I2C interface
Wire.begin();
//Clock.setSecond(50);//Set the second
//Clock.setMinute(59);//Set the minute
//Clock.setHour(11); //Set the hour
//Clock.setDoW(5); //Set the day of the week
//Clock.setDate(31); //Set the date of the month
//Clock.setMonth(5); //Set the month of the year
//Clock.setYear(13); //Set the year (Last two digits of the year)
// Start the serial interface
Serial.begin(115200);
lcd.init(); // initialize the lcd
//lcd.clear();
// Print a message to the LCD.
lcd.backlight();
lcd.setCursor(0, 0);
lcd.print("3w.yarogniew.net");
}
void ReadDS3231()
{
int second,minute,hour,date,month,year,temperature;
second=Clock.getSecond();
minute=Clock.getMinute();
hour=Clock.getHour(h12, PM);
date=Clock.getDate();
month=Clock.getMonth(Century);
year=Clock.getYear();
temperature=Clock.getTemperature();
lcd.setCursor(2, 1);
lcd.print("20");
lcd.print(year,DEC);
lcd.print('-');
lcd.print(month,DEC);
lcd.print('-');
lcd.print(date,DEC);
lcd.print(' ');
lcd.print(hour,DEC);
lcd.print(':');
lcd.print(minute,DEC);
lcd.print(':');
lcd.print(second,DEC);
//lcd.print('\n');
//lcd.print("Temperature=");
//lcd.print(temperature);
//lcd.print('\n');
Serial.print("20");
Serial.print(year,DEC);
Serial.print('-');
Serial.print(month,DEC);
Serial.print('-');
Serial.print(date,DEC);
Serial.print(' ');
Serial.print(hour,DEC);
Serial.print(':');
Serial.print(minute,DEC);
Serial.print(':');
Serial.print(second,DEC);
Serial.print('\n');
Serial.print("Temperature=");
Serial.print(temperature);
Serial.print('\n');
}
void loop() {ReadDS3231();delay(1000);
//Przejście kursora do pierwszej kolumny drugiego wiersza
//lcd.setCursor(2, 1);
//Odczyt oraz wyświetlenie czasu jaki upłynął od ostatniego resetu w sekundach
//time = millis()/1000;
//lcd.print("time:");
//lcd.print(time);
// send what's going on to the serial monitor.
// Start with the year
/* Serial.print("2");
if (Century) { // Won't need this for 89 years.
Serial.print("1");
} else {
Serial.print("0");
}
Serial.print(Clock.getYear(), DEC);
Serial.print('-');
// then the month
Serial.print(Clock.getMonth(Century), DEC);
Serial.print('-');
// then the date
Serial.print(Clock.getDate(), DEC);
Serial.print(' ');*/
// and the day of the week
/*Serial.print(Clock.getDoW(), DEC);
Serial.print(' ');*/
// Finally the hour, minute, and second
/*Serial.print(Clock.getHour(h12, PM), DEC);
Serial.print(':');
Serial.print(Clock.getMinute(), DEC);
Serial.print(':');
Serial.print(Clock.getSecond(), DEC);
// Add AM/PM indicator
if (h12) {
if (PM) {
Serial.print(" PM ");
} else {
Serial.print(" AM ");
}
} else {
Serial.print(" 24h ");
}
// Display the temperature
Serial.print("T=");
Serial.print(Clock.getTemperature(), 2);
// Tell whether the time is (likely to be) valid
if (Clock.oscillatorCheck()) {
Serial.print(" O+");
} else {
Serial.print(" O-");
}*/
// Indicate whether an alarm went off
/*if (Clock.checkIfAlarm(1)) {
Serial.print(" A1!");
}
if (Clock.checkIfAlarm(2)) {
Serial.print(" A2!");
}*/
// New line on display
//Serial.print('\n');
// delay(1000);
// Display Alarm 1 information
/* Serial.print("Alarm 1: ");
Clock.getA1Time(ADay, AHour, AMinute, ASecond, ABits, ADy, A12h, Apm);
Serial.print(ADay, DEC);
if (ADy) {
Serial.print(" DoW");
} else {
Serial.print(" Date");
}
Serial.print(' ');
Serial.print(AHour, DEC);
Serial.print(' ');
Serial.print(AMinute, DEC);
Serial.print(' ');
Serial.print(ASecond, DEC);
Serial.print(' ');
if (A12h) {
if (Apm) {
Serial.print('pm ');
} else {
Serial.print('am ');
}
}
if (Clock.checkAlarmEnabled(1)) {
Serial.print("enabled");
}
Serial.print('\n');
// Display Alarm 2 information
Serial.print("Alarm 2: ");
Clock.getA2Time(ADay, AHour, AMinute, ABits, ADy, A12h, Apm);
Serial.print(ADay, DEC);
if (ADy) {
Serial.print(" DoW");
} else {
Serial.print(" Date");
}
Serial.print(' ');
Serial.print(AHour, DEC);
Serial.print(' ');
Serial.print(AMinute, DEC);
Serial.print(' ');
if (A12h) {
if (Apm) {
Serial.print('pm');
} else {
Serial.print('am');
}
}
if (Clock.checkAlarmEnabled(2)) {
Serial.print("enabled");
}*/
/* display alarm bits
Serial.print('\n');
Serial.print('Alarm bits: ');
Serial.print(ABits, DEC);
*/
/*
Serial.print('\n');
Serial.print('\n');
delay(1000);
// Display the time once more as a test of the getTime() function
Clock.getTime(year, month, date, DoW, hour, minute, second);
Serial.print(year, DEC);
Serial.print("/");
Serial.print(month, DEC);
Serial.print("/");
Serial.print(date, DEC);
Serial.print("day of the week :");
Serial.println(DoW, DEC);
Serial.print(hour, DEC);
Serial.print(":");
Serial.print(minute, DEC);
Serial.print(":");
Serial.println(second, DEC);*/
}
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