| 摘要 |
<p>Function keys control the same, or different functions in the telephone system, depending on the existing switching state. A function controllable by a key is optically displayed. Each function key can control several function steps consecutively settable by a counter in a permanent store in the terminal (SA). Commands generated by the store for each functional step became operative through one and/or several code converters (Ku, MFV) in signal transmission means provided in the speech and/or control wires of the terminal equipment.</p> |
