| 摘要 |
PURPOSE:To prevent the ghost of a character due to the interference between a residual carrier and a carrier sent by the next terminal equipment by starting a selecting sequence or a polling sequence after the carrier from the terminal equipment communicated just before is lost. CONSTITUTION:Prior to the start of a selecting sequence transmitting section 18 or a polling sequence transmission section 19, a residual carrier check section 15 checks the presence of a residual carrier. A carrier display bit exists in a so-called SCF field in an interface control word (ICW) 20 and a carrier discrimination section 16 discriminates the set/reset of the bit. When the bit is reset, the selecting sequence transmission section 18 or the polling sequence transmission section 19 is started. If the carrier from the terminal equipment communicated just before remains, a synchronizing signal character transmission section 17 is started to send a synchronizing signal character or a dummy character. When the transmission of the said character is finished, the carrier discrimination section 16 is restarted by the interruption to repeat the check of the residual carrier.
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