File content as of revision 2:458f9e603814:

#include "mbed.h"

void write_to_master(char);                    //function to write data to master

I2CSlave slave(D14,D15);                       //configuring pins p27, p28 as I2Cslave
Serial pc (USBTX,USBRX);
InterruptIn interrupt(D9);
void FUNC_I2C_WRITE2CDMS(char  * data_send,int length)
{

    int slave_status = 1;
    while(slave_status)
    {                 
            slave.address(0x20);
            if(slave.receive()==1)
            {
                slave_status=slave.write(data_send,length);
                printf("\n In the while loop\n");
                
                if(!slave_status)
                {
                        printf("slave wrote %c to master\n\r",*data_send);
              
                }
                
            }
            
            //slave.stop();
    }
            printf("2 done");
}

void FUNC_I2C_READFCDMS()

{
    printf("\nEntered slave code\n");
    //read_loop=true;
    char *data_rec = new char;
   int slave_status =1;
     
     slave.address(0x20);
                
     
                
     printf("\nentered slave while loop\n");
                //if(slave.receive()==3) 
                while(slave_status==1)
                    slave_status=slave.read(data_rec,1);
                
     if(slave_status==0){printf("1 read %c from master\n\r",*data_rec);}
      //                 read_loop = false;}
                   
     printf("\n done \n \r");
     
     delete data_rec;
    
}
   
void main()
{
    printf("\nStarted slave... waiting for master\n");
    char * data_send = new char;
    *data_send = 'a';
    
    while(1)
    {
        //*(data_send)=pc.getc();
        
        FUNC_I2C_READFCDMS();
        (*data_send)++;
        //wait(1);
    }
}