DMA Controller Structure
5-35
Direct Memory Access (DMA) Controller
5.11 DMA Controller Structure
Figure 5–14 shows the internal data movement paths of the DMA controller,
including data buses and internal holding registers.
Figure 5–14. DMA Controller Data Bus Block Diagram
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DMA read buses
Peripheral bus write
Program memory write
Data memory write
EMIF write
Auxiliary read
Auxiliary write
Peripheral bus read
Program memory read
Data memory read
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Burst FIFO
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CH2 holding
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CH0 holding
5.11.1 Read and Write Buses
Each DMA channel can independently select one of four sources and destinations:
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EMIF
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Internal program memory
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Internal data memory
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Internal peripheral bus
Read and write buses from each source interface to the DMA controller.
The auxiliary channel also has read and write buses. However, since the auxiliary
channel provides address generation for the DMA, the naming convention of its
buses differs. For example, data writes from the auxiliary channel through the
DMA controller are performed through the auxiliary write bus. Similarly, data
reads from the auxiliary channel through the DMA controller are performed
through the auxiliary read bus.