| 摘要 |
Data processing apparatus for connection to a computer and operable to perform data processing functions in response to control signals from the computer, the apparatus comprising input means for receiving said signals (38, 42, 46) on a given line (42) from the computer and energising means (26, 28) for supplying electrical power for operating the apparatus, wherein the energising means is operable to derive said power from said line (42), preferably at least in part from said control signals thereon, or from the voltage applied to the data terminal ready line (48) of the computer. |
