| 摘要 |
PURPOSE:To enable to write the data to the memory, even if the transferred data processing is not finished, by the readout processing of data of processor in response to the interruption signal. CONSTITUTION:The data output device REQ feeds and stores the number of words SC desired to be transferred as data to the memory MEM via the data line D, in response to the transfer permission signal TXSTB from the controller DMAC. After data transfer, the counter CN is counted up, interruption request is given to the interruption line INT, and data is picked up at the processor P for processing. After data processing, the processor P counts down the counter CN. The data output device REQ outputs the transferred data to the data line D after data transmission. Thus, even if the data processing is not done yet with the processor P, the next data can be stored in the memory MEM. |
