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Copy const data from pFlash to Ext RAM

Started by bmbmz123 October 29, 2003
Hello all,

I need your help, since I am unfamiliar with the linker, nor could I
understand its behaviour from the SDK.

I am using internal RAM for data variables.

I want to use external RAM (32K) for large data arrays, of two types:
1. One variable (r/w) data array, and
2. Several const data arrays , that are needed to be copied from
program Flash, at init (because total size > data flash size).

I want to use the internal data RAM for all other data variable, as
access is faster.

I am thinking that maybe all the data copied from ROM to RAM can be
placed in the higher flash area, as all my sw fits in the lower
section - the 827 has two program-flash areas.

So far I used the SDK stationary for all the linker operations.

So my questions are:

1. How do I modify the linker.cmd file to place large variable data
array in the external data ram space.

2. How do I modify the linker.cmd file to place large constant data
arrays (copied from program Flash,) in the external data ram space.

3. Is the copying done automatically by the SDK (as is done when I
use only internal RAM), or do I need to write a routine to do it?

Thank you

boaz