How I get 100 hz frequency in arduino mega 2560

Projects Programming
20

Acoording to u i write a code but now again I am getting only 10 or 11 sample only.

#include "Protocentral_MAX30100.h"  //for PPG MAX30100 sensor library.
#include <Wire.h>                   //for I2C Comm library.
#include "RTClib.h"                 //for RTC library
#include <SPI.h>                    //for SPI comm. library.
#include <SD.h>                     //for SD Card library.
#include <Q2HX711.h>                //for pressure sensor library HX710.

RTC_DS1307 RTC;                     //RTC_DS1307 class object declaration
const int chipSelect = 53;          //chip select pin for arduino mega 2560

#define  REPORTING_PERIOD_MS   10   //delay of 10ms
uint32_t tsLastReport = 0;

int sensorValue= 0;                  // store the gsr sensor value
int ecgs =0;                       // store the ecg sensor value
//-----------------declaration for MAX30100 PPG Sensor----------------
MAX30100 sensor;
uint8_t data_len=8;
uint8_t DataPacketHeader[15];
volatile  long IRR,REDD;
//-----------------declaration for pressur HX710 Sensor----------------
const byte hx711_data_pin  = 3;
const byte hx711_clock_pin = 2;
int avg_val = 0;                                    // variable for stroing raw data.
float pressure, pres_PSI;                                     //before pressure declared as double
Q2HX711 hx711(hx711_data_pin, hx711_clock_pin);

int state =0; //Create empty string called incomingData
const int air_pump = 5; //Pin 7 for connecting Mini Air Pump via ULN2803A driver
const int solenoid = 4; //Pin 6 for connecting solenoid Air valve via ULN2803A driver

void setup() {
  Serial.begin(115200);
  RTC.begin();
 if (! RTC.isrunning()) 
   Serial.println("RTC is  running!");
   RTC.adjust(DateTime(__DATE__, __TIME__));

 while (!Serial)
  {
    ;
  }
  Serial.print("Initializing SD card...");
if (!SD.begin(chipSelect)) 
  {
   Serial.println("Card failed, or not present");
   while (1);
  }
  Serial.println("Card initialized.");
  Wire.begin();
  sensor.begin(pw1600, i50, sr100 );
  sensor.printRegisters();
  pinMode(8, INPUT); // Setup for leads off detection LO +
  pinMode(9, INPUT); // Setup for leads off detection LO -
  pinMode(air_pump, OUTPUT);
  pinMode(solenoid, OUTPUT);
  digitalWrite(air_pump, HIGH); //Inflates pressure cuff
  digitalWrite(solenoid, LOW);
 
 }

void loop() {
  if (Serial.available())
  {
  state = Serial.parseInt();
  if(state == 1)
  {
  //Serial.println("Activated");
    digitalWrite(air_pump, LOW); //Deflates pressure cuff
    digitalWrite(solenoid, HIGH); 
  }
  if (state == 2) {
   //Serial.println("deactivated");
    digitalWrite(air_pump, HIGH); //Inflates pressure cuff
    digitalWrite(solenoid, LOW);
    }
  } 
   
  String dataString = "";
  String dataStringA = "";
  String dataStringB = "";
  String dataStringC = "";
  String dataStringD = "";
  
  dataString  = String(REDD,DEC);
  dataStringA = String(IRR,DEC);
  dataStringB = String(sensorValue);
  dataStringC = String(pres_PSI);
  dataStringD = String(ecgs);
  
  DateTime now = RTC.now(); 
   sensor.readSensor();
   IRR=sensor.IR;
   REDD=sensor.RED;
   DataPacketHeader[0] = 0x0A;
   DataPacketHeader[1] = 0xFA;
   DataPacketHeader[2] = (uint8_t) (data_len);
   DataPacketHeader[3] = (uint8_t) (data_len>>8);
   DataPacketHeader[4] = 0x02;
     
    DataPacketHeader[5] = REDD;
    DataPacketHeader[6] = REDD>>8;
    DataPacketHeader[7] = REDD>>16;
    DataPacketHeader[8] = REDD>>24; 
  
    DataPacketHeader[9] = IRR;
    DataPacketHeader[10] = IRR>>8;
    DataPacketHeader[11] = IRR>>16;
    DataPacketHeader[12] = IRR>>24; 

    DataPacketHeader[13] = 0x00;
    DataPacketHeader[14] = 0x0b;
//
//    for(int i=0; i<15; i++) // transmit the data
//    {
//       Serial.write(DataPacketHeader[i]);
//    }
//-------------GSR Sensor Signal Reading-------------------------------
    sensorValue=analogRead(A0);
  //-------------Pressure Sensor Signal Reading--------------------------
    avg_val =(hx711.read()/100);// add multiple ADC readings
    float pres_volt = avg_val*0.0048828125; 
    pres_volt =  pres_volt - 0.50;
    pres_PSI = pres_volt / 13.33;
//    Serial.print("Pressure = "),Serial.println(pres_PSI);
    pressure = pres_PSI - 0.4;
//-------------ECG Sensor Signal Reading--------------------------    
    ecg(); 
// if (millis() - tsLastReport > REPORTING_PERIOD_MS) {
  File dataFile = SD.open("iitd.txt", FILE_WRITE);
  if (dataFile)
   {
    dataFile.print(now.day(), DEC);
    dataFile.print('/');
    dataFile.print(now.month(), DEC);
    dataFile.print('/');
    dataFile.print(now.year(), DEC);
    dataFile.print(' ');
    dataFile.print(now.hour(), DEC);
    dataFile.print(':');
    dataFile.print(now.minute(), DEC);
    dataFile.print(':');
    dataFile.print(now.second(), DEC);
    dataFile.print(',');
for (int i =0; i<=100; i++){   
    dataFile.print(dataString );
    dataFile.print(',');
    dataFile.print(dataStringA);
    dataFile.print(',');
    dataFile.print(dataStringB);
    dataFile.print(',');
    dataFile.print(dataStringC);
    dataFile.print(',');
    dataFile.println(dataStringD);
    dataFile.close();
  }
  }
 else 
  {
   Serial.println("error opening datalog.txt");
  }
// tsLastReport = millis();
// }
//   Serial.print(now.day(), DEC),Serial.print('/');
//   Serial.print(now.month(), DEC),Serial.print('/');
//   Serial.print(now.year(), DEC),Serial.print(' ');
//   Serial.print(now.hour(), DEC),Serial.print(':');
//   Serial.print(now.minute(), DEC),Serial.print(':');
//   Serial.print(now.second(), DEC),Serial.println();
//   Serial.println(REDD,DEC);
//   Serial.println(IRR,DEC);
//   Serial.print("GSR = "),Serial.println(sensorValue);
//   Serial.print("ECG = "),Serial.println(ecgs);
//   Serial.print("Pressure = "),Serial.println(pres_PSI);
 }
void ecg() {
if((digitalRead(8) == 1) || (digitalRead(9) == 1)){ //check if leads are removed
//Serial.println("leads off!");
}
else
{
 ecgs = analogRead(A1);
// Serial.print("ECG = "),Serial.println(ecgs);
}
}