Hello!
So I have been progressing well with getting my air quality sensor up and running using a Bosch TPH BME280 and CJMCU-1100 VOC sensor with an Arduino Uno.
However, I would like to programme this to take a sample every 15 minutes, with TPH sensor taking a reading for one minute every 14/15 minutes, subsequently followed by the VOC sensor. I would like the ending of the TPH sensor to trigger the VOC sensor to start up. The VOC sensor uses a hot plate method so needs ~3 minutes to start up.
I am just not sure how to programme this, especially since everything i see online uses a relay module.
Here is the code i currently have:
//********************Start of code for TPH sensor*********************** #include <Wire.h> #include "RTClib.h" #include <BME280I2C.h> #include <SPI.h> #include <SD.h> BME280I2C bme; char daysOfTheWeek[7][12] = {"Sunday", "Monday", "Tuesday", "Wednesday", "Thursday", "Friday", "Saturday"}; RTC_DS1307 rtc; uint32_t delayMS; const int chipSelect = 10; const int pingPin = 7; unsigned int rtcd; unsigned int rtcm; unsigned int rtcy; unsigned int rtcs; unsigned int rtcmin; unsigned int rtchr; //define start and end times of desired operation, may be just for relay module though?// //const int OnHour = 12// //const int OnMin = 05// //const int OffHour = 12// //const int OffMin = 06// //This sensor measures changes in VOC gas levels// #define Aout A0 #define Dout 2 void setup() { pinMode(Aout,INPUT); pinMode(Dout,INPUT); // Open serial communications and wait for port to open: Serial.begin(9600); if (! rtc.begin()) { Serial.println("Couldn't find RTC"); while (1); } if (! rtc.isrunning()) { Serial.println("RTC is NOT running!"); // following line sets the RTC to the date & time this sketch was compiled rtc.adjust(DateTime(F(__DATE__), F(__TIME__))); // This line sets the RTC with an explicit date & time, for example to set // January 21, 2014 at 3am you would call: // rtc.adjust(DateTime(2020, 12, 16, 10, 36, 0)); } while(!bme.begin()) { Serial.println("Could not find BME280 sensor!"); delay(1000); } // bme.chipID(); // Deprecated. See chipModel(). switch(bme.chipModel()) { case BME280::ChipModel_BME280: Serial.println("Found BME280 sensor! Success."); break; case BME280::ChipModel_BMP280: Serial.println("Found BMP280 sensor! No Humidity available."); break; default: Serial.println("Found UNKNOWN sensor! Error!"); } Serial.print("Initializing SD card..."); // see if the card is present and can be initialized: if (!SD.begin(chipSelect)) { Serial.println("Card failed, or not present"); // don't do anything more: while (1); } Serial.println("card initialized."); } void loop() { /*****************Get Temp, Pressure and Humidity********************/ float temp(NAN), hum(NAN), pres(NAN); BME280::TempUnit tempUnit(BME280::TempUnit_Celsius); BME280::PresUnit presUnit(BME280::PresUnit_Pa); bme.read(pres, temp, hum, tempUnit, presUnit); float preshpa = (pres/100); //create space for conversion of pascals to hectopascals (hPa) which is more usual measure float corr_temp = (temp-0.0); //create space for correction of temperature according to unique sensor validation (will be different for each sensor) float corr_hum = (hum+0); //create space for correction of humidity according to unique sensor validation (will be different for each sensor) float corr_preshpa = (preshpa+10); //create space for correction of pressure according to unique sensor validation (will be different for each sensor) Serial.print("Temp: "); Serial.print(corr_temp); Serial.print("°"+ String(tempUnit == BME280::TempUnit_Celsius ? 'C' :'F')); Serial.print("\t\tHumidity: "); Serial.print(corr_hum); Serial.print("% RH"); Serial.print("\t\tPressure: "); Serial.print(corr_preshpa); Serial.print(" hPa "); /*********GET VOC ************/ int a=analogRead(Aout); int b=digitalRead(Dout); Serial.print("D0:"); Serial.print(b); Serial.print(" A0:"); Serial.println(a); /*********GET TIME ************/ rtc.adjust(DateTime(F(__DATE__), F(__TIME__))); // uncommented // DateTime now = rtc.now(); Serial.print(now.year(), DEC); Serial.print('/'); Serial.print(now.month(), DEC); Serial.print('/'); Serial.print(now.day(), DEC); Serial.print(" ("); Serial.print(daysOfTheWeek[now.dayOfTheWeek()]); Serial.print(") "); Serial.print(now.hour(), DEC); Serial.print(':'); Serial.print(now.minute(), DEC); Serial.print(':'); Serial.print(now.second(), DEC); Serial.println(); //Serial.print(" since midnight 1/1/1970 = "); //Serial.print(now.unixtime()); //Serial.print("s = "); //Serial.print(now.unixtime() / 86400L); //Serial.println("d"); // DateTime now = rtc.now(); rtcs = now.second(); rtcmin = now.minute(); rtchr = now.hour(); rtcy = now.year(); rtcm = now.month(); rtcd = now.day(); /*********STORE DATA TO SD CARD ************/ // open the file. note that only one file can be open at a time, // so you have to close this one before opening another. File dataFile = SD.open("datalog.csv", FILE_WRITE); // if the file is available, write to it: if (dataFile) { //dataFile.print(cm); dataFile.print(",CM,"); dataFile.print(rtchr); dataFile.print(":"); dataFile.print(rtcmin); dataFile.print(":"); dataFile.print(rtcs); dataFile.print(",TIME,"); dataFile.print(rtcd); dataFile.print("/"); dataFile.print(rtcm); dataFile.print("/"); dataFile.print(rtcy); dataFile.print(",DATE,"); dataFile.print(corr_temp); dataFile.print(",Temperature,"); dataFile.print(corr_preshpa); dataFile.print(",Pressure,"); dataFile.print(corr_hum); dataFile.print(",Humidity,"); dataFile.print(b); dataFile.print(",TVOC Digital,"); dataFile.print(a); dataFile.println(",TVOC Analogue"); delay(1000); dataFile.close(); delay(10); // print to the serial port too: //Serial.println(cm); } // if the file isn't open, pop up an error: else { Serial.println("error opening datalog.csv"); } delay(20); } // ***********************End of Code -- you are DONE!*******************************
