FTD2XX_NET.FTDI.WriteFT232REEPROM C# (CSharp) Method

        public FT_STATUS WriteFT232REEPROM(FT232R_EEPROM_STRUCTURE ee232r)
        {
            // Initialise ftStatus to something other than FT_OK
            FT_STATUS ftStatus = FT_STATUS.FT_OTHER_ERROR;
            FT_ERROR ftErrorCondition = FT_ERROR.FT_NO_ERROR;

            // If the DLL hasn't been loaded, just return here
            if (hFTD2XXDLL == IntPtr.Zero)
                return ftStatus;

            // Check for our required function pointers being set up
            if (pFT_EE_Program != IntPtr.Zero)
            {
                tFT_EE_Program FT_EE_Program = (tFT_EE_Program)Marshal.GetDelegateForFunctionPointer(pFT_EE_Program, typeof(tFT_EE_Program));

                if (ftHandle != IntPtr.Zero)
                {
                    FT_DEVICE DeviceType = FT_DEVICE.FT_DEVICE_UNKNOWN;
                    // Check that it is an FT232R or FT245R that we are trying to write
                    GetDeviceType(ref DeviceType);
                    if (DeviceType != FT_DEVICE.FT_DEVICE_232R)
                    {
                        // If it is not, throw an exception
                        ftErrorCondition = FT_ERROR.FT_INCORRECT_DEVICE;
                        ErrorHandler(ftStatus, ftErrorCondition);
                    }

                    // Check for VID and PID of 0x0000
                    if ((ee232r.VendorID == 0x0000) | (ee232r.ProductID == 0x0000))
                    {
                        // Do not allow users to program the device with VID or PID of 0x0000
                        return FT_STATUS.FT_INVALID_PARAMETER;
                    }

                    FT_PROGRAM_DATA eedata = new FT_PROGRAM_DATA();

                    // Set up structure headers
                    eedata.Signature1 = 0x00000000;
                    eedata.Signature2 = 0xFFFFFFFF;
                    eedata.Version = 2;

                    // Allocate space from unmanaged heap
                    eedata.Manufacturer = Marshal.AllocHGlobal(32);
                    eedata.ManufacturerID = Marshal.AllocHGlobal(16);
                    eedata.Description = Marshal.AllocHGlobal(64);
                    eedata.SerialNumber = Marshal.AllocHGlobal(16);

                    // Check lengths of strings to make sure that they are within our limits
                    // If not, trim them to make them our maximum length
                    if (ee232r.Manufacturer.Length > 32)
                        ee232r.Manufacturer = ee232r.Manufacturer.Substring(0, 32);
                    if (ee232r.ManufacturerID.Length > 16)
                        ee232r.ManufacturerID = ee232r.ManufacturerID.Substring(0, 16);
                    if (ee232r.Description.Length > 64)
                        ee232r.Description = ee232r.Description.Substring(0, 64);
                    if (ee232r.SerialNumber.Length > 16)
                        ee232r.SerialNumber = ee232r.SerialNumber.Substring(0, 16);

                    // Set string values
                    eedata.Manufacturer = Marshal.StringToHGlobalAnsi(ee232r.Manufacturer);
                    eedata.ManufacturerID = Marshal.StringToHGlobalAnsi(ee232r.ManufacturerID);
                    eedata.Description = Marshal.StringToHGlobalAnsi(ee232r.Description);
                    eedata.SerialNumber = Marshal.StringToHGlobalAnsi(ee232r.SerialNumber);

                    // Map non-string elements to structure
                    // Standard elements
                    eedata.VendorID = ee232r.VendorID;
                    eedata.ProductID = ee232r.ProductID;
                    eedata.MaxPower = ee232r.MaxPower;
                    eedata.SelfPowered = Convert.ToUInt16(ee232r.SelfPowered);
                    eedata.RemoteWakeup = Convert.ToUInt16(ee232r.RemoteWakeup);
                    // 232R specific fields
                    eedata.PullDownEnableR = Convert.ToByte(ee232r.PullDownEnable);
                    eedata.SerNumEnableR = Convert.ToByte(ee232r.SerNumEnable);
                    eedata.UseExtOsc = Convert.ToByte(ee232r.UseExtOsc);
                    eedata.HighDriveIOs = Convert.ToByte(ee232r.HighDriveIOs);
                    // Override any endpoint size the user has selected and force 64 bytes
                    // Some users have been known to wreck devices by setting 0 here...
                    eedata.EndpointSize = 64;
                    eedata.PullDownEnableR = Convert.ToByte(ee232r.PullDownEnable);
                    eedata.SerNumEnableR = Convert.ToByte(ee232r.SerNumEnable);
                    eedata.InvertTXD = Convert.ToByte(ee232r.InvertTXD);
                    eedata.InvertRXD = Convert.ToByte(ee232r.InvertRXD);
                    eedata.InvertRTS = Convert.ToByte(ee232r.InvertRTS);
                    eedata.InvertCTS = Convert.ToByte(ee232r.InvertCTS);
                    eedata.InvertDTR = Convert.ToByte(ee232r.InvertDTR);
                    eedata.InvertDSR = Convert.ToByte(ee232r.InvertDSR);
                    eedata.InvertDCD = Convert.ToByte(ee232r.InvertDCD);
                    eedata.InvertRI = Convert.ToByte(ee232r.InvertRI);
                    eedata.Cbus0 = ee232r.Cbus0;
                    eedata.Cbus1 = ee232r.Cbus1;
                    eedata.Cbus2 = ee232r.Cbus2;
                    eedata.Cbus3 = ee232r.Cbus3;
                    eedata.Cbus4 = ee232r.Cbus4;
                    eedata.RIsD2XX = Convert.ToByte(ee232r.RIsD2XX);

                    // Call FT_EE_Program
                    ftStatus = FT_EE_Program(ftHandle, eedata);

                    // Free unmanaged buffers
                    Marshal.FreeHGlobal(eedata.Manufacturer);
                    Marshal.FreeHGlobal(eedata.ManufacturerID);
                    Marshal.FreeHGlobal(eedata.Description);
                    Marshal.FreeHGlobal(eedata.SerialNumber);
                }
            }
            else
            {
                if (pFT_EE_Program == IntPtr.Zero)
                {
                    LogB.Debug("FTD2XX: Failed to load function FT_EE_Program.");
                }
            }
            return ftStatus;
        }

 /// <summary>
 /// Take the previously read EEPROM_STRUCTURE 
 /// and write it back to the FT EEPROM
 /// after elsewhere checking and modifying the 
 /// product description if necessary
 /// </summary>
 /// <param name="dev"></param>
 /// <returns></returns>
 public FTDI.FT_STATUS writeFtdiEEProm(FTDI dev)
 {
     FTDI.FT_STATUS ftStatus = FTDI.FT_STATUS.FT_OK;
     try
     {
         ftStatus = dev.WriteFT232REEPROM(ftEeprom);
     }
     catch (FTDI.FT_EXCEPTION ex)
     {
         throw ex;
     }
     return ftStatus;
 }