Initializing The Device Manager - Analog Devices VisualDSP++ 5.0 Service Manual

Using the Device Manager
of buffers is processed differently, where no significant difference in pro-
cessing exists, they are collectively referred to as simply a buffer within this
text.
In general, applications provide buffers through the device manager API,
where the buffers are processed and then made available again to the appli-
cation. The
adi_dev_Read
which are filled with data that is inbound from the device. The
function provides the device with buffers that contain data sent out
Write
through the device.
Buffers are processed in the order in which they are received. Buffers pro-
vided to a given device need not be a uniform size; each individual buffer
can be any arbitrary size. Further, both one-dimensional and two-dimen-
sional buffers can be provided to a single device. Circular buffers are more
complex (see "Providing Buffers to a Device" on page

Initializing the Device Manager

Before using a device, the application or client must first initialize the
device manager. The client initializes the device manager by calling the
adi_dev_Init
device manager can use for processing. The client decides how much
memory (and from which memory space) to provide the device manager;
the more memory provided, the more physical devices can be simulta-
neously opened.
The device manager requires a contiguous block of memory that can be
thought of two parts—one part is base memory required for the device
manager to instantiate itself, and the other part is memory that is required
to support n number of simultaneously opened device drivers. Macros
(
ADI_DEV_BASE_MEMORY
define the amount of memory (in bytes) required for the base memory and
incremental device driver memory, respectively.
10-8
function provides the device with buffers,
function and passing a portion of memory to it that the
and
ADI_DEV_DEVICE_MEMORY
VisualDSP++ 5.0 Device Drivers and System
) are provided to
Services Manual for Blackfin Processors
adi_dev_
10-15).