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I have a question about the transmission mode of DMA.From the book，i know there are 2 82C37A in PCH（Platform Controller Hub），but is any device in the PC use the same DMAC？ IDE controller command “C8h” means DMA read which is read data from harddisk，before it works, can we
use the command of 82C37 to close the transmission mode of DMA?Or there is an independent DMA controller in the IDE device different from the PCH.Thank you for your answer.