Analog Devices VisualDSP++ 5.0 Service Manual page 437

back to the application. This allows each physical driver to extend the
command IDs and allows them to create their own unique command IDs
that the application can control.
The device manager processes the following commands:
•
ADI_DEV_CMD_GET_2D_SUPPORT
determine if the device supports two-dimensional data movement.
On Blackfin processors, if a device is supported by peripheral
DMA, two-dimensional data movement is provided. If the device
is not supported by peripheral DMA, the command is passed to the
physical driver for determining if the physical driver can support
two-dimensional data.
•
ADI_DEV_CMD_SET_SYNCHRONOUS
device manager in synchronous mode for the given device. The
only processing here is to set the flag in the
ture. This command is never passed to the physical driver, as all
synchronous activity is controlled by the device manager. Hiding
this from the physical driver has the added benefit of physical driv-
ers not caring (nor having to take special processing) to
accommodate synchronous or asynchronous modes. The physical
driver can operate in whatever manner is best suited to the device.
•
ADI_DEV_CMD_SET_DATAFLOW_METHOD
the dataflow method for the given device. If the device is not sup-
ported by peripheral DMA, the device manager takes no action
other than noting the dataflow method and passing the command
along to the physical driver via the
the device is supported by peripheral DMA, the default value used
for the DMA configuration control register is updated with settings
appropriate for the dataflow method. Further, once the dataflow
method is defined by the application, the device manager then has
enough information to open whatever DMA channels are necessary
in support of the device. The physical driver is interrogated via the
adi_pdd_Control
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
– This command is used to
– This command is used to put the
adi_pdd_Control
function as to which DMA controller and
Device Driver Manager
ADI_DEV_DEVICE
– This command is used to set
function. If
struc-
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