Help Porting C/C++ Function to C#

[dvazriel]

Hi, this is the problem i am having:

I have a PC104 with a ADO card. API's are provided to control ADO card, API is a C Compiled DLL. The example code that shows how to use this API is in C++ and as a initial test i want to port some basic fuctions to C#.

This is whats happening:

C++ Code:

void main(void)
{
   char szBuf[512];

   if (!OpenBoard6430(BOARD_NO,0x6430,szBuf, &boardconfig))
      {
      cprintf("\n%s",szBuf);
      cprintf("\nIf an other DM6430 application is running,"
                    " please close it and try again.");
      getch();
      return;
      }
    DEVICE_NO = boardconfig.device_no;

//This is the method signature in the H file:
dllExport BOOL OpenBoard6430(int num, int device_id, LPSTR szBuf,
		BoardConfig *boardconfig );
//BoardConfig is a simple struct with 2 members.

}

This is the C# code i wrote:

public char[] szBuf = new char[512];
        public struct BoardConfig
        {
            int device_no;
            int it_no;
        }
        BoardConfig board;
        [DllImport("drvr6430.dll")]
        public static extern bool OpenBoard6430(int num, int id, char[] szBuf, BoardConfig board);
        
        private void button1_Click(object sender, EventArgs e)
        {
            if (!OpenBoard6430(1, 0x6430, szBuf, board))
            {
               //
            }
            else
            {
                //
            }
        }

When i click the button, i get a trying to write to protected memory exception.
What am i doing wrong?


Any help will be GREATLY appreciated.

Thanks