Operation; Initialization - Analog Devices VisualDSP++ 5.0 Service Manual

The flag service uses an unambiguous naming convention to safeguard
against conflicts with other software libraries provided by ADI or else-
where. To this end, all enumeration values and
prefix, and functions and global variables use the lowercase
ADI_FLAG_
equivalent.
adi_flag_
Each function within the flag service application program interface (API)
returns an error code of the type
vices, a return value of 0 (
A nonzero value indicates an error. Like all system services, flag service
error codes are unique from all other system services. The
include file lists all error codes that the flag service returns.
Parameter checking in the debug versions of the system services library
provides a more complete test of API function parameters and for condi-
tions that may cause errors. ADI strongly recommends that development
work be done using the debug versions of the system service library, and
final test and deployment be done with the release version of the library.

Operation

This section describes the overall operation of the flag service. Details on
the application program interface (API) can be found later in this chapter.

Initialization

Prior to using the flag service, the client must first initialize the service.
In order to initialize the service, the client passes to the initialization func-
tion,
adi_flag_Init
function should the flag service need to protect a critical region of code,
and optionally a contiguous piece of memory that the service can use for
flag callbacks.
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
ADI_FLAG_RESULT
ADI_FLAG_RESULT_SUCCESS
, a parameter that is passed to the critical region
Programmable Flag Service
statements use the
typedef
. Like all system ser-
) indicates no errors.
adi_flag.h
7-3