Send two different data types over I2C?

so m trying send values on i2c master slave. want send both characters , integers , able tell 1 being received. example program shows how @ same time if want send integer larger 2 digit number have split integer on master side , send individual bytes. (char -> 1byte....int -> 2bytes) m trying understand meaning of why example slave receiver sketch reading 2 values, character , byte. if write can send 1 byte @ time master why slave receiver receiving character , and int?

i thinking of having 2 onreceive methods receiving seperate data types doesnt appear can this.

so figured out alternative. wanted send characters because using characters commands , have used byte command. future sake if wants send full integer master writer slave sender here 1 way of doing so.

the master writer sends integer of 700 , command of 0x03 follows

code: [select]

// wire master writer
// nicholas zambetti <http://www.zambetti.com>

// demonstrates use of wire library
// writes data i2c/twi slave device
// refer "wire slave receiver" example use this

// created 29 march 2006

// example code in public domain.


#include <wire.h>
int val = 700;
int myarray[2];

void setup()
{
  wire.begin(); // join i2c bus (address optional master)
  myarray[0] = (byte) (val & 0xff);
  myarray[1] = (byte) ((val >> 8) & 0xff);
}

byte x = 0x03;

void loop()
{
  send_data();
  delay(1000);
}


void send_data()
{
  wire.begintransmission(100); // transmit device #4
  wire.write(myarray[0]);        // sends 5 bytes
  wire.write(x);              // sends 1 byte  
  wire.endtransmission();    // stop transmitting
  delay(500);
  
  wire.begintransmission(100); // transmit device #4
  wire.write(myarray[1]);        // sends 5 bytes
  wire.write(x);              // sends 1 byte  
  wire.endtransmission();    // stop transmitting
  delay(500);
}



the slave receiver receiving int of 700 , command of 0x03 follows

code: [select]

// wire slave receiver
// nicholas zambetti <http://www.zambetti.com>

// demonstrates use of wire library
// receives data i2c/twi slave device
// refer "wire master writer" example use this

// created 29 march 2006

// example code in public domain.


#include <wire.h>
volatile int = 0;
volatile int number;
int mybytes[2];
void setup()
{
  wire.begin(100);                // join i2c bus address #4
  wire.onreceive(receiveevent); // register event
  serial.begin(115200);           // start serial output
}

void loop()
{
  delay(100);
}

// function executes whenever data received master
// function registered event, see setup()
void receiveevent(int howmany)
{
  while(1 < wire.available()) // loop through last
  {
     mybytes[i] = wire.read(); // receive byte character
    //serial.println(c);         // print character
  }
  byte x = wire.read();    // receive byte integer
  serial.println(x);         // print integer
  i++;
  if(i == 2)
  {
    i = 0;
    number = mybytes[0] | mybytes[1] << 8;
    serial.println("the number is: ");
    serial.println(number);
  }
}

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