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static inline void insw(unsigned short port, void *addr, unsigned char cnt)
{
   __asm volatile("rep; insw"
       : "+D" (addr), "+c" (cnt)
       : "d" (port)
       : "memory");
}

static inline void outsw(unsigned short port, const void *addr, unsigned char cnt){
   __asm volatile("rep; outsw" : "+S" (addr), "+c" (cnt) : "d" (port));
}

int read_sector(int LBA) {
   int count = 1;      //number of sectors to read     
   char slavebit =0;   //0 for master device 1 for slave   sets bit 5 in 1f6
   int stat;

   outb(0x3f6, 0x02);   //disable interrupts

   outb(0x1F6, (0xE0 | (slavebit <<  4) | (LBA >> 24 & 0x0F)));

   //waste some time
   outb(0x1f1, 0x00);

   //set the sector count
   outb(0x1f2, (unsigned char)count);
   sleep(1);
   stat = ide_polling(0, 0);
      if(stat != 0)
         return stat;
   //send the low 8 bits of lbs to 1f3
   outb(0x1f3, (unsigned char)LBA);
   sleep(1);
   stat = ide_polling(0, 0);
      if(stat != 0)
         return stat;
   //send the middle 8 bits to 1f4
   outb(0x1f4, (unsigned char)(LBA >> 8));
   sleep(1);
   stat = ide_polling(0, 0);
      if(stat != 0)
         return stat;
   //send the high 8 to 1f5
   outb(0x1f5, (unsigned char)(LBA >> 16));
   sleep(1);
   stat = ide_polling(0, 0);
   if(stat != 0)
      return stat;

   //issue a read sectors command
   outb(0x20, 0x1f7);
   sleep(1);
   stat = ide_polling(0, 0);
      if(stat != 0)
         return stat;

   //eat 256 words form the buffer
   unsigned char ide_buff[256];
   printf("DATA BEFORE: %s\n", ide_buff);

   insw(0x1f0, ide_buff, 512);
   
   ide_polling(0,0);
   
   printf("DATA AFTER: %s", ide_buff);

}