| 摘要 |
PURPOSE:To attain data transmission and reception with simple constitution surely and accurately by controlling a selector to select 2nd clock when it is detected that the operating timing of a modulator-demodulator section side is regulated by the 2nd clock. CONSTITUTION:A clock detector 18 is provided, which controls the selector 17 to select the 2nd clock when it is detected that the operating timing of a modulator-demodulator section side 15 is regulated by the 2nd clock. That is, when a transmission signal element timing ST2 of an oscillator built in the MODEM 15 is selected, the selected transmission signal element timing ST2 is sent to the selector 17 and the clock detector 18 via an interface 14. When the clock detector 18 detects the transmission signal element timing ST2, the detector 18 operates the selector 17, which selects the transmission signal element timing ST2 generated from an oscillator of the MODEM 15. Thus, the data is sent and received with simple constitution surely and accurately. |
