| 摘要 |
PURPOSE:To surely prevent mis-transmittal of a data signal by collating identification information added to the data signal with identification information possessed by a slave station using a time slot and validating the received data signal only when both information sets are coincident. CONSTITUTION:An ID number of a terminal equipment connecting to a slave station BB is added to a data signal for each time slot at the time of transmission and a received ID number is collated with a stored ID number at the reception and only when both numbers are coincident, the reception data is sent to terminal equipments 391-39m. In the case of dissidence, the data is invalidated. Thus, even when the line assignment is in error in the master station AA or the slave station BB and no data is able to be sent from other terminal equipments, the data is not transferred unconditionally to the terminal equipments 391-39m. Thus, mis-transmittal of the data signal is surely prevented. |
