LPC2141 - USB HID problems

I am developing an HID device using an LPC2141. For the descriptors I followed the instructions of the thread http://www.keil.com/forum/docs/thread11137.asp. Using USBSource I can see that enumeration works, that data is sent to the host and that data is received by my device. The LPC is able to recognize data and responses accordingly. I therefore strongly believe that my code for the LPC is correct.

The problem I have now is that I can not receive data on the host side. I am using the C# example from http://www.lvr.com/hidpage.htm which successfully sends data but always fails on receiving. Whenever I try to read from the device I get a "Readfile timeout" error. I am working on this bug now for days already but I really can't find a solution.

So does anyone have any hints regarding this issue? What about ReportIDs, I had problems with that when I tried to send data, do I have to watch out for that also when I try to receive data?

Below are my descriptors but I guess they are okay:

#define HID_INREPORT_SIZE           0x40
#define HID_OUTREPORT_SIZE          0x40


/* USB Standard Device Descriptor */
const BYTE USB_DeviceDescriptor[] = {
  USB_DEVICE_DESC_SIZE,              /* bLength */
  USB_DEVICE_DESCRIPTOR_TYPE,        /* bDescriptorType */
  WBVAL(0x0110), /* 1.10 */          /* bcdUSB */
  0x00,                              /* bDeviceClass */
  0x00,                              /* bDeviceSubClass */
  0x00,                              /* bDeviceProtocol */
  USB_MAX_PACKET0,                   /* bMaxPacketSize0 */
  WBVAL(0x1DA8),                     /* idVendor */
  WBVAL(0x1301),                     /* idProduct */
  WBVAL(0x0100), /* 1.00 */          /* bcdDevice */
  0x04,                              /* iManufacturer */
  0x12,                              /* iProduct */
  0x20,                              /* iSerialNumber */
  0x01                               /* bNumConfigurations */
};



/* USB Configuration Descriptor */
/*   All Descriptors (Configuration, Interface, Endpoint, Class, Vendor */
const BYTE USB_ConfigDescriptor[] = {

/* Configuration 1 */
  USB_CONFIGUARTION_DESC_SIZE,       /* bLength */
  USB_CONFIGURATION_DESCRIPTOR_TYPE, /* bDescriptorType */
  WBVAL(                             /* wTotalLength */
    USB_CONFIGUARTION_DESC_SIZE +
    USB_INTERFACE_DESC_SIZE     +
    HID_DESC_SIZE               +
    USB_ENDPOINT_DESC_SIZE      +
    USB_ENDPOINT_DESC_SIZE
  ),
  0x01,                              /* bNumInterfaces */
  0x01,                              /* bConfigurationValue */
  0x00,                              /* iConfiguration */
  USB_CONFIG_BUS_POWERED /*|*/       /* bmAttributes */
/*USB_CONFIG_REMOTE_WAKEUP*/,
  USB_CONFIG_POWER_MA(500),          /* bMaxPower */

/* Interface 0, Alternate Setting 0, HID Class */
  USB_INTERFACE_DESC_SIZE,           /* bLength */
  USB_INTERFACE_DESCRIPTOR_TYPE,     /* bDescriptorType */
  0x00,                              /* bInterfaceNumber */
  0x00,                              /* bAlternateSetting */
  0x02,                              /* bNumEndpoints */
  USB_DEVICE_CLASS_HUMAN_INTERFACE,  /* bInterfaceClass */
  HID_SUBCLASS_NONE,                 /* bInterfaceSubClass */
  HID_PROTOCOL_NONE,                 /* bInterfaceProtocol */
  0x5C,                              /* iInterface */

/* HID Class Descriptor */
/* HID_DESC_OFFSET = 0x0012 */
  HID_DESC_SIZE,                     /* bLength */
  HID_HID_DESCRIPTOR_TYPE,           /* bDescriptorType */
  WBVAL(0x0100), /* 1.00 */          /* bcdHID */
  0x00,                              /* bCountryCode */
  0x01,                              /* bNumDescriptors */
  HID_REPORT_DESCRIPTOR_TYPE,        /* bDescriptorType */
  WBVAL(HID_REPORT_DESC_SIZE),       /* wDescriptorLength */

/* Endpoint, HID Interrupt In */
  USB_ENDPOINT_DESC_SIZE,            /* bLength */
  USB_ENDPOINT_DESCRIPTOR_TYPE,      /* bDescriptorType */
  USB_ENDPOINT_IN(1),                /* bEndpointAddress */
  USB_ENDPOINT_TYPE_INTERRUPT,       /* bmAttributes */
  WBVAL( HID_INREPORT_SIZE ),        /* wMaxPacketSize */  // = 64 byte
  0x20,          /* 32ms */          /* bInterval */

/* Endpoint, HID Interrupt Out */
  USB_ENDPOINT_DESC_SIZE,            /* bLength */
  USB_ENDPOINT_DESCRIPTOR_TYPE,      /* bDescriptorType */
  USB_ENDPOINT_OUT(1),               /* bEndpointAddress */
  USB_ENDPOINT_TYPE_INTERRUPT,       /* bmAttributes */
  WBVAL( HID_OUTREPORT_SIZE ),       /* wMaxPacketSize */  // = 64 byte
  0x20,          /* 32ms */          /* bInterval */

/* Terminator */
  0                                  /* bLength */
};

For sending and receiving I am using circular buffers:

void USB_Configure_Event (void) {
  if (USB_Configuration) {                  /* Check if USB is configured */
    usbtxbuf.data[0] = 0;
    usbtxbuf.data[1] = 255;
    USB_WriteEP(0x81, usbtxbuf.data, 2 );
  }
}




void USB_EndPoint1 (DWORD event) {

    uint8 size;

    switch (event) {


        case USB_EVT_IN:

            if ( cbuf_hasMsgs( &usbtxqueue ) == ERR_CBUF_HASMSGS )
            {
                // send message from queue
                if ( cbuf_get( &usbtxqueue, &usbtxbuf ) == ERR_NOERROR )
                {
                    USB_WriteEP(0x81, usbtxbuf.data, usbtxbuf.size );
                }
            }
            else
            {
                // send bulk message
                usbtxbuf.size = 0;
                USB_WriteEP(0x81, usbtxbuf.data, usbtxbuf.size );
            }

            break;


        case USB_EVT_OUT:

            size = USB_ReadEP( 0x01, rxbuf );
            if ( size > 0 )
            {
                cbuf_putdata( &usbrxqueue, MODULE_USB, rxbuf, size );
            }

            break;

    }

}