| 摘要 |
PURPOSE:To prevent the adverse effect on audio channel due to the mixture of data signals, by converting a plurality of bits corresponding to the audio/data identifying bit in advance to one of low level audio signals compulsively. CONSTITUTION:When an audio/data identifying V/D bit is 1, that is, a data is displayed, a flip-flop 202 is se to 1, a gate 301 in turned off and a gate 302 is turned on. Further, a 64kb/s signal of a lead 101 is thrown away and the content of a low level audio signal generating circuit 401 is sequentially outputted with the clock in 64kHz through the gates 302, 303 to an output register 501. On the other hand, the bit pattern of the low level audio signal selected not giving any hindrance to the audio channel is tored to the content of the circuit 401 and since it is looped back through a lead 402, the same content can be outputted repetitively with a given period at all times. |
