I use BulkOutEndPt and BulkInEndPt instead of BulkEndPt.
int len = 3;
byte buf = new byte[len];
buf = (byte)Commands.VR_SET_INTEGRATION_TIME;
buf = (byte)(integrationTime & 0xff);
buf = (byte)((integrationTime >> 8) & 0xff);
if (myDev.BulkOutEndPt.XferData(ref buf, ref len) == true)
if (buf == 0)
len = 1;
if (myDev.BulkInEndPt.XferData(ref buf, ref len) == true)
BulkEndPoint would point to the first Bulk Endpoint of your device. If it is a OUT endpoint was it configured to send 16 bytes?
If it is a IN endpoint then if it was configured properly then it should have received the data and XferData would have returned success. Please let us know your configuration.