Just wanted to update everyone and a big thanks. I found out that the Nano I was using did not have enough RAM to run both the SD card and the OLED display. All things are working now and I revised my code into "pockets" so I could comment things and test them individually. Anyway, Just wanted to give a big thank you as you guys really helped me out, I learned a ton on this project!
Mike
[code]
#include <Wire.h>
#include "RTClib.h" //Jeelab's fantastic RTC library.
#include<SPI.h> //SD card uses spi bus
#include<SD.h> //contains library functions
#include <Adafruit_GFX.h>
#include <Adafruit_SSD1306.h>
#define SCREEN_WIDTH 128 // OLED display width, in pixels
#define SCREEN_HEIGHT 64 // OLED display height, in pixels
#define OLED_RESET 4
#define CSPIN 10 //if using DPin-4, it does not require to set direction
#define button1 9 //Button B1 is connected to Arduino pin 9
#define button2 8 //Button B2 is connected to Arduino pin 10
File myFile; //file pointer variavle declaration
Adafruit_SSD1306 display(OLED_RESET);
RTC_DS3231 rtc; //RTC definition
const int ledPin1 = A1;// the number of the LED pin
const int ledPin2 = A2;
int ledState = LOW; // ledState used to set the LED
unsigned long LEDpreviousMillis = 0; // will store last time LED was updated
unsigned long SDpreviousMillis = 0;
const long LEDinterval = 2000; // interval at which to blink (milliseconds)
const long SDinterval = 50000;
void setup(void) {
display.begin(SSD1306_SWITCHCAPVCC, 0x3C); // initialize with the I2C addr
display.clearDisplay();
display.display();
display.setTextColor(WHITE, BLACK);
display.drawRect(117, 55, 3, 3, WHITE); // Put degree symbol ( ° )
draw_text(0, 55, "TEMPERATURE =", 1);
draw_text(122, 55, "C", 1);
pinMode(A1, OUTPUT);
pinMode(A2, OUTPUT);
Serial.begin(9600);
Wire.begin();
rtc.begin();
rtc.adjust(DateTime(F(__DATE__), F(__TIME__))); //-Not sure if this is needed as the RTC is currently set
//rtc.adjust(DateTime(2021, 12, 31, 11, 59, 57)); //set date-time manualy:yr,mo,dy,hr,mn,sec
pinMode(button1, INPUT_PULLUP);
pinMode(button2, INPUT_PULLUP);
pinMode(CSPIN, OUTPUT);
delay(1000);
if (!SD.begin(CSPIN))
{
Serial.println("Card failed, or not present");
return;
}
Serial.println("card initialized.");
SD.begin(CSPIN); //SD Card is initialized
//SD.remove("TEST.txt"); //remove any existing file with this name
if (SD.exists("flight.txt")) {
Serial.println("flight.txt exists.");
} else {
Serial.println("flight.txt doesn't exist.");
}
// open a new file and immediately close it:
Serial.println("Creating example.txt...");
myFile = SD.open("flight.txt", FILE_WRITE);
myFile.close();
myFile = SD.open("flight.txt", FILE_WRITE); //file created and opened for writing
if (myFile) { //file has really been opened
myFile.print("\r\n");
myFile.print("Date");
myFile.print(" , ");
myFile.print("Time");
myFile.print(" , ");
myFile.println("Temp");
}
myFile.close();
}
char Time[] = " : : ";
char Calendar[] = " / /20 ";
char temperature[] = " 00.00";
char temperature_msb;
byte i, second, minute, hour, day, date, month, year, temperature_lsb;
void display_day() {
switch (day) {
case 1: draw_text(0, 0, " SUNDAY ", 1); break;
case 2: draw_text(0, 0, " MONDAY ", 1); break;
case 3: draw_text(0, 0, " TUESDAY ", 1); break;
case 4: draw_text(0, 0, "WEDNESDAY", 1); break;
case 5: draw_text(0, 0, "THURSDAY ", 1); break;
case 6: draw_text(0, 0, " FRIDAY ", 1); break;
default: draw_text(0, 0, "SATURDAY ", 1);
}
}
void DS3231_display() {
// Convert BCD to decimal
second = (second >> 4) * 10 + (second & 0x0F);
minute = (minute >> 4) * 10 + (minute & 0x0F);
hour = (hour >> 4) * 10 + (hour & 0x0F);
date = (date >> 4) * 10 + (date & 0x0F);
month = (month >> 4) * 10 + (month & 0x0F);
year = (year >> 4) * 10 + (year & 0x0F);
// End conversion
Time[7] = second % 10 + 48;
Time[6] = second / 10 + 48;
Time[4] = minute % 10 + 48;
Time[3] = minute / 10 + 48;
Time[1] = hour % 10 + 48;
Time[0] = hour / 10 + 48;
Calendar[9] = year % 10 + 48;
Calendar[8] = year / 10 + 48;
Calendar[4] = month % 10 + 48;
Calendar[3] = month / 10 + 48;
Calendar[1] = date % 10 + 48;
Calendar[0] = date / 10 + 48;
if (temperature_msb < 0) {
temperature_msb = abs(temperature_msb);
temperature[0] = '-';
}
else
temperature[0] = ' ';
temperature_lsb >>= 6;
temperature[2] = temperature_msb % 10 + 48;
temperature[1] = temperature_msb / 10 + 48;
if (temperature_lsb == 0 || temperature_lsb == 2) {
temperature[5] = '0';
if (temperature_lsb == 0) temperature[4] = '0';
else temperature[4] = '5';
}
if (temperature_lsb == 1 || temperature_lsb == 3) {
temperature[5] = '5';
if (temperature_lsb == 1) temperature[4] = '2';
else temperature[4] = '7';
}
draw_text(60, 0, Calendar, 1); // Display the date (format: dd/mm/yyyy)
draw_text(10, 24, Time, 2); // Display the time
draw_text(75, 55, temperature, 1); // Display the temperature
}
void blink_parameter() {
byte j = 0;
while (j < 10 && digitalRead(button1) && digitalRead(button2)) {
j++;
delay(25);
}
}
byte edit(byte x_pos, byte y_pos, byte parameter) {
char text[3];
sprintf(text, "%02u", parameter);
while (!digitalRead(button1)); // Wait until button B1 released
while (true) {
while (!digitalRead(button2)) { // If button B2 is pressed
parameter++;
if (i == 0 && parameter > 31) // If date > 31 ==> date = 1
parameter = 1;
if (i == 1 && parameter > 12) // If month > 12 ==> month = 1
parameter = 1;
if (i == 2 && parameter > 99) // If year > 99 ==> year = 0
parameter = 0;
if (i == 3 && parameter > 23) // If hours > 23 ==> hours = 0
parameter = 0;
if (i == 4 && parameter > 59) // If minutes > 59 ==> minutes = 0
parameter = 0;
sprintf(text, "%02u", parameter);
draw_text(x_pos, y_pos, text, 1);
delay(200); // Wait 200ms
}
draw_text(x_pos, y_pos, " ", 1);
blink_parameter();
draw_text(x_pos, y_pos, text, 1);
blink_parameter();
if (!digitalRead(button1)) { // If button B1 is pressed
i++; // Increament 'i' for the next parameter
return parameter; // Return parameter value and exit
}
}
}
void draw_text(byte x_pos, byte y_pos, char *text, byte text_size) {
display.setCursor(x_pos, y_pos);
display.setTextSize(text_size);
display.print(text);
display.display();
}
void blinkLED() {
unsigned long LEDcurrentMillis = millis();
if (LEDcurrentMillis - LEDpreviousMillis >= LEDinterval) {
// save the last time you blinked the LED
LEDpreviousMillis = LEDcurrentMillis;
// if the LED is off turn it on and vice-versa:
if (ledState == LOW) {
ledState = HIGH;
} else {
ledState = LOW;
}
// set the LED with the ledState of the variable:
digitalWrite(ledPin1, ledState);
digitalWrite(ledPin2, ledState);
}
}
void settime() {
i = 0;
while (!digitalRead(button1)); // Wait for button B1 release
while (true) {
while (!digitalRead(button2)) { // While button B2 pressed
day++; // Increment day
if (day > 7) day = 1;
display_day(); // Call display_day function
delay(200); // Wait 200 ms
}
draw_text(0, 0, " ", 1);
blink_parameter(); // Call blink_parameter function
display_day(); // Call display_day function
blink_parameter(); // Call blink_parameter function
if (!digitalRead(button1)) // If button B1 is pressed
break;
}
//set position of text when editing on button press
date = edit(60, 0, date); // Edit date
month = edit(80, 0, month); // Edit month
year = edit(110, 0, year); // Edit year
hour = edit(14, 9, hour); // Edit hours
minute = edit(50, 9, minute); // Edit minutes
// Convert decimal to BCD
minute = ((minute / 10) << 4) + (minute % 10);
hour = ((hour / 10) << 4) + (hour % 10);
date = ((date / 10) << 4) + (date % 10);
month = ((month / 10) << 4) + (month % 10);
year = ((year / 10) << 4) + (year % 10);
// End conversion
// Write data to DS3231 RTC
Wire.beginTransmission(0x68); // Start I2C protocol with DS3231 address
Wire.write(0); // Send register address
Wire.write(0); // Reset sesonds and start oscillator
Wire.write(minute); // Write minute
Wire.write(hour); // Write hour
Wire.write(day); // Write day
Wire.write(date); // Write date
Wire.write(month); // Write month
Wire.write(year); // Write year
Wire.endTransmission(); // Stop transmission and release the I2C bus
delay(200); // Wait 200ms
}
void displayoled() {
Wire.beginTransmission(0x68); // Start I2C protocol with DS3231 address
Wire.write(0); // Send register address
Wire.endTransmission(false); // I2C restart
Wire.requestFrom(0x68, 7); // Request 7 bytes from DS3231 and release I2C bus at end of reading
second = Wire.read(); // Read seconds from register 0
minute = Wire.read(); // Read minuts from register 1
hour = Wire.read(); // Read hour from register 2
day = Wire.read(); // Read day from register 3
date = Wire.read(); // Read date from register 4
month = Wire.read(); // Read month from register 5
year = Wire.read(); // Read year from register 6
Wire.beginTransmission(0x68); // Start I2C protocol with DS3231 address
Wire.write(0x11); // Send register address
Wire.endTransmission(false); // I2C restart
Wire.requestFrom(0x68, 2); // Request 2 bytes from DS3231 and release I2C bus at end of reading
temperature_msb = Wire.read(); // Read temperature MSB
temperature_lsb = Wire.read(); // Read temperature LSB
display_day();
DS3231_display();
delay(50);
}
void loop() {
if (!digitalRead(button1)) {
settime();
}
writeToSD(); //record data on SD card
blinkLED();
displayoled();
}
//===================================================
void writeToSD() { //records temperature data of LM35 sensor at 2-min interval (this is an example)
unsigned long SDcurrentMillis = millis();
if (SDcurrentMillis - SDpreviousMillis >= SDinterval) {
// save the last time you blinked the LED
SDpreviousMillis = SDcurrentMillis;
myFile = SD.open("flight.txt", FILE_WRITE);
if (myFile) {
float myTemp = rtc.getTemperature();
DateTime nowDT = rtc.now();
myFile.print("\r\n");
myFile.print(nowDT.day(), DEC); myFile.print('/');
myFile.print(nowDT.month(), DEC); myFile.print('/');
myFile.print(nowDT.year(), DEC); myFile.print(" , ");
myFile.print(nowDT.hour(), DEC); myFile.print(':');
myFile.print(nowDT.minute(), DEC); myFile.print(':');
myFile.print(nowDT.second(), DEC); myFile.print(" , ");
myFile.print(myTemp, 2);
myFile.close();
Serial.println("temperature updated");
}
}
}
[/code]