ScsiReadHidden readHidden = new ScsiReadHidden();
readHidden.serialize();//produce an array which is readHidden.cbwBuffer.array()
int iRes = conn.bulkTransfer(epOUT, readHidden.cbwBuffer.array(), 31, 2000);
iRes = conn.bulkTransfer(epIN, readHidden.cswBuffer, 512, 2000);