| 摘要 |
The invention relates to a multiplexer and a demultiplexer, the multiplexer being intended for combining a digital signal, a digital additional information and stuff bits into a time-division multiplex signal and the demultiplexer for separating the digital signal from the time-division multiplex signal. The multiplexer comprises a flexible buffer (1, 6) and a multiplex circuit (10) for composing a pulse frame of the additional information and the digital signal fed from the buffer (1, 6). The flexible buffer comprises a byte buffer (1) and a bit buffer (6), into which byte buffer (1) the digital signal is written continuously byte by byte at a speed depending on the clock frequency of the digital signal and from which it is read byte by byte into the bit buffer (6) at a speed depending on the frequency of the pulse frame stopping the reading for the time required by the additional information and in which bit buffer (6) justification byte (Z) bits to be replaced by fixed stuff bits (R) are offset to the beginning of the following byte. |
