Creating Circular Buffers - Analog Devices VisualDSP++ 5.0 Service Manual

Creating Circular Buffers

Buffer[i].pNext
}
Buffer[NUM_BUFFERS - 1].pNext
// give the buffers to the driver to send out
Result = adi_dev_Write(Handle, ADI_DEV_2D, (ADI_DEV_BUFFER
*)Buffer);
Creating Circular Buffers
The
ADI_DEV_CIRCULAR_BUFFER
the driver processes in a circular manner. Applications populate the vari-
ous fields of the buffer to completely describe the data to the device driver.
For circular buffers, applications populate the following fields of the
DEV_CIRCULAR_BUFFER
• – If the buffer is provided to the
Data
this field contains the starting address of the data sent out through
the device. If the buffer is provided to the
tion, this field contains the starting address of where the device
driver stores data received in from the device.
•
ElementWidth
element sent out or read in.
•
SubBufferCount
into which the data is divided.
•
SubBufferElementCount
ments in each sub-buffer.
10-26
// terminate the chain of buffers
data structure is used to describe data that
structure:
– This field indicates the width (in bytes) of each
– This field specifies the number of sub-buffers
– This field specifies the number of ele-
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
= &Buffer[i+1];
= NULL;
adi_dev_Write()
adi_dev_Read()
ADI_
function,
func-