Reference to a Structure

Hello,

how do I reference a array to a structure, in a way when I change the value of that array I also affect the value of the structure, and when I affect the value of the structure I also affect the value of the array ?

I tryed to do something with pointer to the structure, since a pointer to a structure is very similar to array. I have done something like this :

Code:

---

typedef structu
{
  unsigned a1:1;
  unsigned a2:1;
  unsigned a3:1;
  .
  .
  .
  unsigned a8:1;
}Bits;

int main()
{
  Coils objCoil;
  Coils *ptrCoil;
  ptrCoil = & objCoil;

  for(int i = 0; i < 8; i++)
  {
      ptrCoil[i] = 1;
  }

}

---

Thanks and best regards,
BoSCHoW.

hope you mean by Coils your Bits struct - and no, you cannot access struct members by index - only by name

objCoil->a1 =1;
objCoil->a2 =1;
etc

It is possible, lets say that I have a struct:

Code:

---

typedef struct
{
  unsigned a1:1;
  .
  .
  .
  .
  .
  unsigned a2000:1;
}Coils;

---

and i have a function like this:

Code:

---

void transferBytes(unsigned char *source, unsigned char *dest, unsigned short quantity)
{
      for(int i = 0; i < quantity; i++)
      dest[i] = source[i];
}

---

In the main function I just have to call the main function and write in the correct parameters:

Code:

---

int main()
{
      Coils objCoils;
      Coils *ptrCoils;
      ptrCoils = &objCoils;
      unsigned char dest[260];
      unsigned short quantity = 20;

      transferBytes((unsigned char*)&ptrCoils, (unsigned char*)&dest, quantity);
}

---

Thanks and best
regards,
BoSCHoW.

Quote:

---

It is possible, lets say that I have a struct:

---

And how do you predict what byte is finished in what member of the struct?

If I will need to access that struct members in an array like manner - I would provide some macro for this...