Question { Siemens, 19892 }
In the field of microprocessor what is DMA?why it is used?
Answer
Direct memory access (DMA) is a method of transferring data
between system memory and I/O devices without requiring
intervention by the microprocessor.DMA is more efficient
than programmed I/O, in which the microprocessor reads the
data from the sending device and then writes it to the
receiving device.In DMA data transfers, data can bypass the
system microprocessor as it moves between system memory and
I/O devices. DMA improves server performance because the
microprocessor does not have to interrupt its processing
activities to manage data transfers.