Running eZdsp F28335 external RAM

Matt Boothe said:

I am developing an application using the eZdsp F28335. The application will eventually run from internal flash, however I am running from internal RAM during development. The problem is I have run out of internal RAM. I would like to execute from external RAM instead.

Is this the basic strategy?

1. Modify the linker command file to locate .cinit, .pinit, .text, codestart in ZONE7A.
2. Modify the linker command file to locate a new XINTF setup function to RAML0 (since XINTF cannot be configured in code running from XINTF).
3. Near the beginning of the application, but after the C environment has been initialized, call the XINTF setup function. The purpose of this step is to avoid running with the default maximum wait states.
4. Before loading with Code Composer Studio, run a GEL to enable the XINTF. The purpose of this step is to allow Code Composer Studio to load the application into external RAM.
5. Load the program with Code Composer Studio. Up until the XINTF setup function executes, expect slow performance.

Does that sound right? And if so, am I making it too complicated? Is there an easier way?

Matt,

You are on track.  As part of step (4) you can also have the gel file configure the waitstates of the XINTF.  In the gel file if you put this into the "OnReset" and the "OnPreFileLoad" this setup will be done automatically whenever you perform these debugger actions.  This can be helpful during debug.

The gel file provided with the header files and peripheral examples has this, it is just commented out.    Also there is an example "xintf_run_from" in the header files and peripheral examples that shows a project that does basically what you are proposing.

Regards,

Lori