Opening A Device - Analog Devices VisualDSP++ 5.0 Service Manual

Using the Device Manager
function, the client can reuse the memory that was supplied to the device
manager via the
manager must be reinitialized in order to be used again.
In many embedded systems, the device manager is never
terminated.

Opening a Device

After the device manager has been initialized, in order to use a device, the
client must first open the device with the
The client passes in parameters indicating the device driver it wants to
open (the
pEntryPoint
open (the
DevNumber
(inbound, outbound, or both), and so on. The client also passes in the
handle to the DMA service the device manager and physical drivers to use.
This parameter can be NULL if the client knows DMA is not used.
The
pDeviceHandle
manager stores the handle to the device driver that is being opened.
All subsequent API calls for this device that is being opened must include
this handle. The
passes back to the client with each call to the client's callback function.
Two other parameters are passed into the
are also callback-related. The
deferred callback service that is used by the device driver to call the client's
callback function. If
specified deferred callback service for all callbacks. If
all callbacks are live; meaning they are not deferred and are executed
immediately (typically at interrupt time). The
points to the client's callback function.
10-10
function. Once terminated, the device
adi_dev_Init()
parameter), the instance of the device it wants to
parameter), the direction it wants data to flow
parameter points to a location where the device
is a parameter that the device manager
ClientHandle
DCBHandle
is non-NULL, the device driver uses the
DCBHandle
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
API function.
adi_dev_Open()
function. They
adi_dev_Open()
parameter is a handle to the
DCBHandle
ClientCallback
is NULL,
parameter