| 摘要 |
PURPOSE:To perform data transfer at high speed without increasing the number of signal lines, by setting a mode at a DMA mode by analyzing a reception data, and performing DMA transfer until the completion processing of a telegram is performed by an interruption signal. CONSTITUTION:A multi-parallel data received at a reception data signal line 11 and a strobe signal line 12 is fetched in a reception response circuit 1, and the busy of a reception processing is transmitted to a transmitter via a busy signal line 13. The reception data is stored in a reception buffer 3, and a microprocessor 2 analyzes the reception data, and when the data is a bit of DMA start information, the processor executes a DMA transfer instruction on the circuit 1, and sets the mode at a DMA transfer mode. When the reception data is transferred from the circuit 1 to the buffer 3, and also, a time monitoring time 4 arrives at a set time, the transfer is completed and the completion processing of the telegram by sending it to the interruption signal line 20. In such a way, it is possible to perform the data transfer at high speed without increasing the number of the signal lines. |
