Sdram Initialization Prior To Loading An Executable; Initialization - Analog Devices VisualDSP++ 5.0 Service Manual

SDRAM Initialization Prior to Loading an
Executable
Applications that require code (and/or data) to be located in SDRAM at
load time require the SDRAM controller to be initialized beforehand.
This is the case for all applications where instruction and/or data caching
are enabled. However, the EBIU service's initialization routine,
adi_ebiu_Init()
There are two ways to load an application into the processor core:
• Through an emulator session connected to the VisualDSP++
IDDE
• From flash memory or a device attached to the SPI port when the
processor is reset
In the first case, it is imperative that the Use XML reset values option is
selected in the Target Options dialog box (available through the Settings
menu). This ensures that the SDRAM is correctly (if not optimally) con-
figured prior to the application loading. Once loaded, the application's
use of the power management services and EBIU services ensures that the
SDRAM is optimally configured.
When the application is not loaded from within an emulator session, it is
necessary for the boot loader to initialize SDRAM prior to loading the
application. This is achieved by using an initialization block as described
in the VisualDSP++ 5.0 Loader and Utilities manual, where the example
given demonstrates the initialization of SDRAM.
This initialization block code is compiled into an executable and is passed
to the loader via the
field of the Load:Options page of the Project Options dialog box. A sepa-
rate project is thus required for the initialization block. An example
initialization block project is provided in the relevant directory (for the
processor) under the
VisualDSP++ 5.0 Device Drivers and System
Services Manual for Blackfin Processors
, is not executed until after the application has loaded.
filename option or in the Initialization file
–init
Blackfin\ldr\init_code
Power Management Module
directory of the
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