In the field of microprocessor what is DMA?why it is used?
Answer Posted / ritesh saha
DMA stands for Direct Memory Access.
DMA is used to transfer data between system memory and IO
devices.DMA has 2 pins namely HOLD and HLDA.The former holds
an instruction that is to be transferred.After that,an
acknowledge signal is sent which is known as HLDA.After
transfer is completed,DMA removes HOLD signal and the
processor removes HLDA signal and starts from where it let
off.
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