In Series/1, a control block that contains information required by the hardware to relate a device handler to a hardware device address. It is used by device handlers to develop I/O requests and save the status of I/O operations.; 在IBM Series/1中的一種控制塊,其中含有使設備處理程序與硬件設備地址聯系起來的 硬件所需的信息。設備處理程序用它來提出輸入輸出請求和保存輸入輸出的狀態(tài)。