| 摘要 |
PURPOSE:To collect untransmitted data automatically from a terminal equipment which recovers from a power failure, by resending data, preceding the last transmitted data by a prescribed number of blocks, from the terminal equipment after the recovery from the power failure and by receiving the data a stored number of blocks behind at a collector side. CONSTITUTION:When data is received from a terminal equipment within a prescribed time, the received block data in a transmitting buffer is transferred to a memory in a collector. When the contents of the storage area is an initial flag, this block data is considered to be of new kind and the operation is repeated until a final flag is confirmed in the storage area. When the initial flag is not confirmed in a step S7, the current and last block data are considered to be coincident and the control is transferred to a step S15, where when they are found unequal, an error is discriminated to move a step S16, thereby comparing the current and last block numbers with each other. When the current number is less than the last one, the terminal equipment is in a power failure state and after it recovers, it is judged that the same block is resent, so that the recollection of the data starting at halfway block data is started. |
