Send Sensors Data in Packet Serially

I am using Arduino mega for this project. I have two sensors data (streams of bytes) but now I want following things:

  1. to send these two sensors data into a single packet, in which these two sensors data are gathered. I mean I want to have a packet in which I have oxygen, heart rate and pedometer values.

  2. I want to send acknowledge bit at the end which confirms that all data is received and send new data now.

  3. I have to add device name in packet for all devices.

  4. I have to set timer to upload data only when user want.

Can anyone tell me how to do it. Code for both sensors are given below. I have already try a lot of ways but all in vain. I am not expert of Arduino please help me. I will be very thankful for your suggestions and time.

For sensor 1

#include <Wire.h>
#include "MAX30105.h"
#include "spo2_algorithm.h"


MAX30105 particleSensor;


#define MAX_BRIGHTNESS 255

#if defined(__AVR_ATmega328P__) || defined(__AVR_ATmega168__)
//Arduino Uno doesn't have enough SRAM to store 100 samples of IR led data and red led data in 32-bit format
//To solve this problem, 16-bit MSB of the sampled data will be truncated. Samples become 16-bit data.
uint16_t irBuffer[100]; //infrared LED sensor data
uint16_t redBuffer[100];  //red LED sensor data
#else
uint32_t irBuffer[100]; //infrared LED sensor data
uint32_t redBuffer[100];  //red LED sensor data
#endif

int32_t bufferLength; //data length
int32_t spo2; //SPO2 value
int8_t validSPO2; //indicator to show if the SPO2 calculation is valid
int32_t heartRate; //heart rate value
int8_t validHeartRate; //indicator to show if the heart rate calculation is valid
uint16_t checkSum = 0;

byte pulseLED = 11; //Must be on PWM pin
byte readLED = 13; //Blinks with each data read

byte ledBrightness = 60; //Options: 0=Off to 255=50mA
byte sampleAverage = 4; //Options: 1, 2, 4, 8, 16, 32
byte ledMode = 2; //Options: 1 = Red only, 2 = Red + IR, 3 = Red + IR + Green
byte sampleRate = 100; //Options: 50, 100, 200, 400, 800, 1000, 1600, 3200
int pulseWidth = 411; //Options: 69, 118, 215, 411
int adcRange = 4096; //Options: 2048, 4096, 8192, 16384

void setup()
{
  
}

void loop()
{
  Serial.begin(9600);
  wait_for_Max30102();
  start_signal();
  if (!particleSensor.begin(Wire, I2C_SPEED_FAST)) //Use default I2C port, 400kHz speed
  {
    Serial.println(F("MAX30105 was not found. Please check wiring/power."));
    while (1);
  }

  Serial.println(F("Attach sensor to finger with rubber band. Press any key to start conversion"));
  //while (Serial.available() == 0) ; //wait until user presses a key
  Serial.read();



  particleSensor.setup(ledBrightness, sampleAverage, ledMode, sampleRate, pulseWidth, adcRange); //Configure sensor with these settings
  bufferLength = 100; //buffer length of 100 stores 4 seconds of samples running at 25sps

  //read the first 100 samples, and determine the signal range
  for (byte i = 0 ; i < bufferLength ; i++)
  {
    while (particleSensor.available() == false) //do we have new data?
      particleSensor.check(); //Check the sensor for new data

    redBuffer[i] = particleSensor.getRed();
    irBuffer[i] = particleSensor.getIR();
    particleSensor.nextSample(); //We're finished with this sample so move to next sample

    /*Serial.print(F("red="));
    Serial.print("\t");
    Serial.print(redBuffer[i], BIN);
    Serial.print("\t");
    Serial.print(redBuffer[i], DEC);
    Serial.print("\n");
    Serial.print(F(", ir="));
    Serial.print("\t");
    Serial.println(irBuffer[i], BIN);
    Serial.print("\t");
    Serial.print(irBuffer[i], DEC);
    Serial.print("\n");*/
  }

  //calculate heart rate and SpO2 after first 100 samples (first 4 seconds of samples)
  maxim_heart_rate_and_oxygen_saturation(irBuffer, bufferLength, redBuffer, &spo2, &validSPO2, &heartRate, &validHeartRate);

  //Continuously taking samples from MAX30102.  Heart rate and SpO2 are calculated every 1 second
  while (1)
  {
    //dumping the first 25 sets of samples in the memory and shift the last 75 sets of samples to the top
    for (byte i = 25; i < 100; i++)
    {
      redBuffer[i - 25] = redBuffer[i];
      irBuffer[i - 25] = irBuffer[i];
    }

    //take 25 sets of samples before calculating the heart rate.
    for (byte i = 75; i < 100; i++)
    {
      while (particleSensor.available() == false) //do we have new data?
        particleSensor.check(); //Check the sensor for new data

      digitalWrite(readLED, !digitalRead(readLED)); //Blink onboard LED with every data read

      redBuffer[i] = particleSensor.getRed();
      irBuffer[i] = particleSensor.getIR();
      particleSensor.nextSample(); //We're finished with this sample so move to next sample


      checkSum = redBuffer[i] + irBuffer[i] + heartRate + validHeartRate + spo2 + validSPO2;

      //send samples and calculation result to terminal program through UART
      Serial.print(F("RED: "));
      Serial.print("\t");
      Serial.print(redBuffer[i], BIN);
      Serial.print("\t");
      Serial.print(redBuffer[i], DEC);
      Serial.println("");
      
      Serial.print(F("IR: "));
      Serial.print("\t");
      Serial.print(irBuffer[i], BIN);
      Serial.print("\t");
      Serial.print(irBuffer[i], DEC);
      Serial.println("");

      Serial.print(F("HR: "));
      Serial.print("\t");
      Serial.print(heartRate, BIN);
      Serial.print("\t");
      Serial.print("\t");
      Serial.print(heartRate, DEC);
      //Serial.println("\t");
      //Serial.print("(HRvalid = ");
      //Serial.print("\t");
      //Serial.print(validHeartRate, BIN);
      //Serial.print("\t");
      //Serial.print(validHeartRate, DEC);
      //Serial.print((" )"));
      Serial.println("");
      
      Serial.print(F("SPO2: "));
      Serial.print("\t");
      Serial.print(spo2, BIN);
      Serial.print("\t");
      Serial.print("\t");
      Serial.print(spo2, DEC);
      //Serial.println("\t");
      //Serial.print("(SPO2Valid = "); 
      //Serial.println(validSPO2, BIN);
      //Serial.print("\t");
      //Serial.println(validSPO2, DEC);
      //Serial.print(" )");
      Serial.print("\n");
      Serial.println("");

      Serial.print(F("Checksum Byte: "));
      Serial.print("\t");
      Serial.print(checkSum, BIN); 
      Serial.print("\t");
      if((byte)checkSum == (byte)(redBuffer[i] + irBuffer[i] + heartRate + validHeartRate + spo2 + validSPO2)){Serial.print("(CHECKSUM_OK)");}
      else {Serial.print("(CHECKSUM_ERROR)");}
      Serial.println("\n");
      Serial.println("\n");
      Serial.println("");
      Serial.println("");
      Serial.println("");
      delay(1000);
    }

    //After gathering 25 new samples recalculate HR and SP02
    maxim_heart_rate_and_oxygen_saturation(irBuffer, bufferLength, redBuffer, &spo2, &validSPO2, &heartRate, &validHeartRate);

  }
  Serial.end(); 
}

void wait_for_Max30102()
{
delay(2000);
}

void start_signal(){
pinMode(readLED, OUTPUT);
pinMode(pulseLED, OUTPUT);
digitalWrite(pulseLED, LOW); 
digitalWrite(readLED, LOW); 
delay(18);
digitalWrite(pulseLED, HIGH);
digitalWrite(readLED, HIGH);
pinMode(pulseLED, INPUT);
pinMode(readLED, INPUT);
digitalWrite(pulseLED, HIGH);
digitalWrite(readLED, HIGH);
}

For sensor 2

#include <Wire.h>

#define DEVICE (0x53)    //ADXL345 device address
#define TO_READ (6)        //num of bytes we are going to read each time (two bytes for each axis)

#define offsetX   -10.5       // OFFSET values
#define offsetY   -2.5
#define offsetZ   -4.5

#define gainX     257.5        // GAIN factors
#define gainY     254.5
#define gainZ     248.5

byte buff[TO_READ] ;    //6 bytes buffer for saving data read from the device
char str[512];                      //string buffer to transform data before sending it to the serial port

int x,y,z, X;

int xavg, yavg,zavg, steps=0, flag=0;
int xval[15]={0}, yval[15]={0}, zval[15]={0};
int threshhold = 60.0;

uint16_t checkSum = 0;

void setup(){}

void loop()
{
for(unsigned int x = 0; x < 5; x++)
{ clv(); }
Serial.end();
}


void start_signal(){
  writeTo(DEVICE, 0x2D, 0);      
  writeTo(DEVICE, 0x2D, 16);
  writeTo(DEVICE, 0x2D, 8); 
}

void clv(){
  Wire.begin();        // join i2c bus (address optional for master)
  Serial.begin(9600);  // start serial for output
  start_signal();
  //Turning on the ADXL345
  
  int regAddress = 0x32;    //first axis-acceleration-data register on the ADXL345
  
  readFrom(DEVICE, regAddress, TO_READ, buff); //read the acceleration data from the ADXL345
  
   //each axis reading comes in 10 bit resolution, ie 2 bytes.  Least Significat Byte first!!
   //thus we are converting both bytes in to one int
  x = (((int)buff[1]) << 8) | buff[0];   
  y = (((int)buff[3])<< 8) | buff[2];
  z = (((int)buff[5]) << 8) | buff[4];
  
//we send the x y z values as a string to the serial port 
 //sprintf(str, "%d %d %d", x, y, z);
 //Serial.print(str);
 //Serial.print(10, byte());
 
  Serial.print("X = ");
  Serial.println(x);
  Serial.print("Y = ");
  Serial.println(y);
  Serial.print("Z = ");
  Serial.println(z);
  
 //write steps
  X = ArduinoPedometerSteps();
  Serial.print("steps = ");
  Serial.println(X);
  Serial.println(" ");
  
  //It appears that delay is needed in order not to clog the port
  Serial.print(F("X: "));
  Serial.print("\t");
  Serial.print(x, BIN);
  Serial.print("\t");
  Serial.print(x, DEC);
  Serial.print("\n");

  Serial.print(F("Y: "));
  Serial.print("\t");
  Serial.print(y, BIN);
  Serial.print("\t");
  Serial.print(y, DEC);
  Serial.print("\n");

  Serial.print(F("Z: "));
  Serial.print("\t");
  Serial.print(z, BIN);
  Serial.print("\t");
  Serial.print(z, DEC);
  Serial.print("\n");
  Serial.print(F("steps: "));
 Serial.print("\t");
 Serial.print(X, BIN);
 Serial.print("\t");
 Serial.print(X, DEC);
 Serial.println("\n");
 
checkSum = x + y + z + X;

 Serial.print(F("Checksum Byte: "));
 Serial.print("\t");
 Serial.print(checkSum, BIN); 
 Serial.print("\t");
 if((byte)checkSum == (byte)(x + y + z + X)){Serial.print("(CHECKSUM_OK)");}
 else {Serial.print("(CHECKSUM_ERROR)");}
 Serial.println("\n");
 Serial.println("\n");
 Serial.println("");
 Serial.println("");
 Serial.println("");
 delay(150);
}

//---------------- Functions
//Writes val to address register on device
void writeTo(int device, byte address, byte val) {
   Wire.beginTransmission(device); //start transmission to device 
   Wire.write(address);        // send register address
   Wire.write(val);        // send value to write
   Wire.endTransmission(); //end transmission
}

//reads num bytes starting from address register on device in to buff array
void readFrom(int device, byte address, int num, byte buff[]) {
  Wire.beginTransmission(device); //start transmission to device 
  Wire.write(address);        //sends address to read from
  Wire.endTransmission(); //end transmission
  
  Wire.beginTransmission(device); //start transmission to device
  Wire.requestFrom(device, num);    // request 6 bytes from device
  
  int i = 0;
  while(Wire.available())    //device may send less than requested (abnormal)
  { 
    buff[i] = Wire.read(); // receive a byte
    i++;
  }
  Wire.endTransmission(); //end transmission
}


//Get pedometer.

int ArduinoPedometerSteps(){
    int acc=0;
    int totvect[15]={0};
    int totave[15]={0};
    int xaccl[15]={0};
    int yaccl[15]={0};
    int zaccl[15]={0};
    for (int i=0;i<15;i++)
    {
      xaccl[i]= x;
      delay(1);
      yaccl[i]= y;
      delay(1);
      zaccl[i]= z;
      delay(1);
      totvect[i] = sqrt(((xaccl[i]-xavg)* (xaccl[i]-xavg))+ ((yaccl[i] - yavg)*(yaccl[i] - yavg)) + ((zval[i] - zavg)*(zval[i] - zavg)));
      totave[i] = (totvect[i] + totvect[i-1]) / 2 ;
      //Serial.print("Total Average = ");
      //Serial.println(totave[i] );
      
      //delay(50);
  
      //cal steps 
      if (totave[i]>threshhold && flag==0)
      {
         steps=steps+1;
         flag=1;
      }
      else if (totave[i] > threshhold && flag==1)
      {
          //do nothing 
      }
      if (totave[i] <threshhold  && flag==1)
      {
        flag=0;
      }
     // Serial.print("steps=");
     // Serial.println(steps);
     return(steps);
    }
  delay(100); 
 }

Where is the data going and in what representation is the data? I mean is the data to be sent in binary or ASCII? What sort of processing is available on the other end? What will be the size of each packet in bytes?

Why are you opening an closing the serial port in that for loop?
Why such a slow baud rate?

Data is sending in both binary and decimal form(not in ASCII form). I just want to make a packet of data which will be send to android cloud for user to get information he/she require and for storage purpose . The size of packet can be 32 or 64 bytes, there is no restriction on size of data. I have to connect this setup to hc-06 Bluetooth module which works on 9600 baud rate.