| 摘要 |
PURPOSE:To delete the undesired data and to attain the effective use of an internal memory by using a means to detect the undesired data and inhibit the transfer of them to a memory and a means ending the transfer of data when the prescribed data is detected and stopping the transfer of the subsequent data. CONSTITUTION:In a calling sequence the plus codes following a plus code 52 and the SYN code for time film are not needed. Thus the working of a DMA data transfer part 8 is completed when the plus code is detected after a calling request is received and the transfer is stopped for the subsequent data. A means which detects the SYN code and two sets of plus codes when the transmission is through with the selection signal is provided for the transfer of signals A and B of the following data train and also for the end of the calling sequence. Then the part 8 is started again to stop the transfer of both SYN codes 54 and 55. At the same time, a plus code 58 is detected and the calling sequence is completed. In such a way, the transfer of many undesired plus codes and SYN codes to a memory and only the effective data can be transferred. |
