UMAT

代码说明：

说明：  通用串行總線是一種通用接口，可實現設備與主機控制器（如個人計算機）之間的通信。它連接外圍設備，如數碼相機，鼠標，鍵盤，打印機，掃描儀，媒體設備，外部硬盤驅動器和閃存驅動器。(A Universal Serial Bus is a common interface that enables communication between devices and a host controller such as a personal computer . It connects peripheral devices such as digital cameras, mice, keyboards, printers, scanners, media devices, external hard drives and flash drives.)