| 摘要 |
PROBLEM TO BE SOLVED: To read data out of a memory device and to send the read data to a serial interface within a little number of times of DMA transfer. SOLUTION: This device is provided with buses 4 and 5, microprocessor 1, memory device 3, DMA transfer control means 2 for performing a DMA transfer interruption to the microprocessor 1 corresponding to a DMA transfer request signal, performing the DMA transfer of data from the memory device 3 to a serial interface A6 when the microprocessor 1 releases the bus, outputting a pulse signal each time data are sent out just for a prescribed data size, stopping DMA transfer when a DMA transfer stop signal is inputted in the middle of series of DMA transfer and recovering the stopped DMA transfer when the microprocessor 1 uses the bus 5 in the state of stopping, and divided counter for outputting the DMA transfer stop signal to the DMA transfer control means 2 when the input time value of the pulse signal is matched with a count stop value.
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