Dma Channel To Peripheral Mapping - Analog Devices VisualDSP++ 5.0 Service Manual

Theory of Operation
The streaming sub-mode allows the client to alter this behavior. When the
streaming sub-mode is enabled, the DMA manager never pauses the DMA
controller; this allows the DMA transfers to occur at the maximum
throughput rate.
When streaming, the client is required to ensure the following conditions:
• The channel always has descriptors to process and never runs out of
descriptors.
• The system timing is such that the DMA manager can service the
callback interrupt for any descriptor tagged for a callback, before
another descriptor on the same channel that is tagged for callback
is processed.
These conditions can be met fairly easily in most systems.

DMA Channel to Peripheral Mapping

The Blackfin processor allows the user to change the default mapping of
the various DMA-supported peripherals to the various DMA channels.
Typically, however, the mappings for the memory DMA channels are
fixed and cannot be changed.
The DMA manager provides two functions,
adi_dma_SetMapping()
the mapping of DMA channels to peripherals. These functions can be
called at any time after the DMA manager is initialized, but they must be
processed before the channel is opened.
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, that allow the client to easily detect and change
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
adi_dma_GetMapping()
and