PCF8574_library/examples/Arduino4Leds4ButtonsWithInterrupt/Arduino4Leds4ButtonsWithInterrupt.ino
2020-03-13 21:52:51 +01:00

81 lines
1.8 KiB
C++

/*
KeyPressed and leds with interrupt
by Mischianti Renzo <http://www.mischianti.org>
https://www.mischianti.org/2019/01/02/pcf8574-i2c-digital-i-o-expander-fast-easy-usage/
*/
#include "Arduino.h"
#include "PCF8574.h"
// For arduino uno only pin 1 and 2 are interrupted
#define ARDUINO_UNO_INTERRUPTED_PIN 2
// Function interrupt
void keyPressedOnPCF8574();
// Set i2c address
PCF8574 pcf8574(0x38, ARDUINO_UNO_INTERRUPTED_PIN, keyPressedOnPCF8574);
unsigned long timeElapsed;
void setup()
{
Serial.begin(115200);
pcf8574.pinMode(P0, INPUT_PULLUP);
pcf8574.pinMode(P1, INPUT_PULLUP);
pcf8574.pinMode(P2, INPUT);
pcf8574.pinMode(P3, INPUT);
pcf8574.pinMode(P7, OUTPUT);
pcf8574.pinMode(P6, OUTPUT, HIGH);
pcf8574.pinMode(P5, OUTPUT);
pcf8574.pinMode(P4, OUTPUT, LOW);
pcf8574.begin();
timeElapsed = millis();
}
unsigned long lastSendTime = 0; // last send time
unsigned long interval = 4000; // interval between sends
bool startVal = HIGH;
bool keyPressed = false;
void loop()
{
if (keyPressed){
uint8_t val0 = pcf8574.digitalRead(P0);
uint8_t val1 = pcf8574.digitalRead(P1);
uint8_t val2 = pcf8574.digitalRead(P2);
uint8_t val3 = pcf8574.digitalRead(P3);
Serial.print("P0 ");
Serial.print(val0);
Serial.print(" P1 ");
Serial.print(val1);
Serial.print(" P2 ");
Serial.print(val2);
Serial.print(" P3 ");
Serial.println(val3);
keyPressed= false;
}
if (millis() - lastSendTime > interval) {
pcf8574.digitalWrite(P7, startVal);
if (startVal==HIGH) {
startVal = LOW;
}else{
startVal = HIGH;
}
lastSendTime = millis();
Serial.print("P7 ");
Serial.println(startVal);
}
}
void keyPressedOnPCF8574(){
// Interrupt called (No Serial no read no wire in this function, and DEBUG disabled on PCF library)
keyPressed = true;
}