'lacks a cast' error - new to C++

Help! I am new to C++ and need to write a routine to pass a 2 dimensional array into a function that will determine whether or not the array is a Magic Square. On the function call:

IsMagic = TestMagic(myArray[500][500], dimension);

I get the error

passing `int' to argument 1 of `TestMagic(int(*)[500], int)' lacks a cast.

Why? And why does it show as int(*)[500] instead of int[500][500]?

Thanks

Andrew

Code:

---

#include<iostream.h>

         
  bool TestMagic(int PassedSquare[500][500], int ArrayDimension)
//this is not yet all of the code that will go into this function 
  {
      int sum;       
      for (int x = 1; x <= ArrayDimension; x++)
      {
        sum = sum + PassedSquare[x][x];
      }
 
      cout << endl;       
      cout << "Left-Right Diagonal is: " << sum;
      return true;
  }

         
  int main()
         
  {
      int myArray[500][500];
      int dimension;
      bool IsMagic;
 
      cout << "Enter array size (minimum 1, maximum 500), or 0 to exit the program: ";
      cin >> dimension; //user enters desired array size
 
      while (dimension > 0)
      {
      //instruct user to enter a value for each array element
        for (int x = 1; x <= dimension; x++)
        {
            for (int y = 0; y < dimension; y++)
            {
              cout << "Enter the value for " << x << ", " << y << ": ";
              cin >> myArray[x][y];
              cout << endl;
            }
        }
     
              //call function TestMagic and pass it the array and its dimensions
//this is where I get the error
        IsMagic = TestMagic(myArray[500][500], dimension);       
     
        if (IsMagic = true)
            cout << "Yes";
        else       
            cout << "No";
     
        cout << endl;
        cout << "Enter array size (minimum 1, maximum 500), or 0 to exit the program: ";
        cin >> dimension; //user enters desired array size       
      }
      return 0;
  }

---

never mind, the line

IsMagic = TestMagic(myArray[500][500], dimension);

should have been

IsMagic = TestMagic(myArray, dimension);

'cause the first one only passes element [500][500]