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#define DHT_PIN 4
#define CE_DISPLAY 5
#define RST_DISPLAY A2
#define DC_DISPLAY A3
#define DIN_DISPLAY 7
#define CLK_DISPLAY 8
#define SN "Clock + Temperature"
#define SV "1.0"
#define DHT_TYPE DHT22
#define MY_RADIO_NRF24
#define MY_TRANSPORT_WAIT_READY_MS 10000
#include <MySensors.h>
#include <U8g2lib.h>
#include <DHT.h>
#include <time.h>
volatile unsigned long rawTime;
unsigned long timer1 = 0;
unsigned long getTimeDelay = 600000;
unsigned long timer2 = 0;
int getDHTDelay = 3000;
unsigned long timer3 = 0;
unsigned int sendDelay = 60000;
float h, t;
char outdoorTemp[50];
float lastT;
U8G2_PCD8544_84X48_1_4W_SW_SPI u8g2(U8G2_R0, /* clock=*/ CLK_DISPLAY, /* data=*/ DIN_DISPLAY, /* cs=*/ CE_DISPLAY, /* dc=*/ DC_DISPLAY, /* reset=*/ RST_DISPLAY); // Nokia 5110 Display
DHT dht(DHT_PIN, DHT_TYPE);
MyMessage tempMsg(0, V_TEMP);
volatile struct tm * localTime;
void before()
{
u8g2.begin();
Serial.begin(115200);
u8g2.firstPage();
do {
initScreen();
} while ( u8g2.nextPage() );
dht.begin();
delay(2000);
}
void setup() {
setupTime();
timer1 = millis();
t = dht.readTemperature();
h = dht.readHumidity();
timer2 = millis();
send(tempMsg.set(t, 0));
lastT = t;
timer3 = millis();
}
void presentation()
{
present(0, S_TEMP);
present(1, S_INFO); //Info sensor to request outdoor tempereture
sendSketchInfo(SN, SV);
request(1, V_TEXT);
}
void setupTime() //setting up timer and interrupt for seconds counter
{
cli();
//set timer1 interrupt at 1Hz
TCCR1A = 0;// set entire TCCR1A register to 0
TCCR1B = 0;// same for TCCR1B
TCNT1 = 0;//initialize counter value to 0
// set compare match register for 1hz increments
OCR1A = 15624;// = (16*10^6) / (1*1024) - 1 (must be <65536)
// turn on CTC mode
TCCR1B |= (1 << WGM12);
// Set CS10 and CS12 bits for 1024 prescaler
TCCR1B |= (1 << CS12) | (1 << CS10);
// enable timer compare interrupt
TIMSK1 |= (1 << OCIE1A);
sei();
requestTime();
}
ISR(TIMER1_COMPA_vect)
{
rawTime++; //increment seconds counter
}
void float2string(float n, char* output)
{
char aChar[5];
char bChar[4];
if (n > 0.0) {
strcpy(aChar, "+");
} else if (n < 0.0) {
strcpy(aChar, "-");
}
dtostrf(n, 4, 1, bChar);
sprintf(output, "%s%s", aChar, bChar);
}
void initScreen() //function to show message on screen during node start
{
u8g2.setFont(u8g2_font_profont12_tr);
u8g2.drawStr(42 - (u8g2.getStrWidth("Connecting to") / 2), 13, "Connecting to");
u8g2.drawStr(42 - (u8g2.getStrWidth("a MySensors") / 2), 26, "a MySensors");
u8g2.drawStr(42 - (u8g2.getStrWidth("network.") / 2), 39, "network");
}
void mainScreen()
{
u8g2.setDrawColor(1);
u8g2.setFontMode(1);
u8g2.drawBox(0, 0, 84, 8);
u8g2.setDrawColor(0);
u8g2.setFont(u8g2_font_profont10_tf);
localTime = localtime(&rawTime); //using standart AVR time.h library to convert seconds counter into local time
char date[30];
strftime(date, 30, "%d.%m.%y %R", localTime); //constructing a string with date and time
u8g2.drawStr(42 - (u8g2.getStrWidth(date) / 2), 7, date);
u8g2.setDrawColor(1);
u8g2.setFont(u8g2_font_maniac_tr);
char val[5];
float2string(t, val); //converting float value from dht11 to a string
u8g2.drawStr(42 - (u8g2.getStrWidth(val) / 2), 36, val);
u8g2.setFont(u8g2_font_profont10_tf);
u8g2.drawStr(5, 47, outdoorTemp);
itoa((int)h, val, 10); //I don't need precision for humidity procentage, otherwise you can use dtostrf()
u8g2.drawStr(70 - u8g2.getStrWidth(val), 47, val);
u8g2.setFont(u8g2_font_open_iconic_thing_1x_t);
u8g2.drawStr(71, 47, "\x48");
}
boolean isTime(unsigned long *timeMark, unsigned long timeInterval) //time counter function for non-blocking delays
{
if (millis() - *timeMark >= timeInterval) {
*timeMark = millis();
return true;
}
return false;
}
void loop()
{
if (isTime(&timer1, getTimeDelay)) { //request time from controller once in 10 minutes
requestTime();
}
if (isTime(&timer2, getDHTDelay)) { //polling DHT sensor and printing values to serial
t = dht.readTemperature();
h = dht.readHumidity();
Serial.print("Temperature: ");
Serial.print(t);
Serial.println("°");
Serial.print("Humidity: ");
Serial.print(h);
Serial.println("%");
}
if (isTime(&timer3, sendDelay)) { //sending temperature to controller once in 30 seconds
if (t != lastT) {
send(tempMsg.set(t, 0));
request(1, V_TEXT);
lastT = t;
}
}
u8g2.firstPage(); //this section is for screen handling
do {
mainScreen();
} while ( u8g2.nextPage() );
}
void receive(const MyMessage &message) //receiving an outdoor reading from the controller and constructing a string to display
{
if (message.type == V_TEXT) {
sprintf(outdoorTemp, "%sC%s", message.getString(), "\xb0");
}
}
void receiveTime(uint32_t ts)
{
rawTime = ts - UNIX_OFFSET; //substructing an offset from received timestamp, since time.h doesn't use Unix count
localTime = localtime(&rawTime); //updating seconds timer with accurate value
timer1 = millis();
}
