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Hello all,

I am currently writing an algorithm using the 6711DSK board in which I
attempt to allocate a 2D array. Unfortunately, it seems that I can't
allocate a very large array without malloc() returning NULL.
Presumably this is because I am not accessing the external memory.
This may be a silly question, but how exactly do I store and access
data in external memory? Is it just a question of increasing the heap
size?

Many thanks,

Edward Buckley.

Hi,
I work with TMS..5402, have being writing only nobody answer.
5402 have 1 Mbytes addressable, 4 kB internal; all upper memory is
external, I use over .asm function with commands "reada/writa".

Cheers
Victor

Vic wrote:
>
> Hi,
> I work with TMS..5402, have being writing only nobody answer.
> 5402 have 1 Mbytes addressable, 4 kB internal; all upper memory is
> external, I use over .asm function with commands "reada/writa".
>
> Cheers
> Victor

You make interesting and accurate statements. Do you have a question?

Jerry
--
Engineering is the art of making what you want from things you can get.
¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯ ¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯¯

Edward Buckley wrote:
>
> Hello all,
>
> I am currently writing an algorithm using the 6711DSK board in which I
> attempt to allocate a 2D array. Unfortunately, it seems that I can't
> allocate a very large array without malloc() returning NULL.
> Presumably this is because I am not accessing the external memory.
> This may be a silly question, but how exactly do I store and access
> data in external memory? Is it just a question of increasing the heap
> size?
>
> Many thanks,
>
> Edward Buckley.

Edward,

This is not a silly question at all. On the contrary, if the 67x tools
work similarly to the 54x/55x tools, then you're in for quite a
learning curve. Also caveat this advice since I've never done exactly this,
but I have done my fair share of hacking the relevent tool files in similar
ways.

The way I understand it, you have to do it in a linker command file. The .sysmem
section has to exist in at least one source file, then in the linker command
file point it into a defined memory section that points to your external
memory. Something like this:

*****************Begin Linker Command File***********************
-heap 08000h

MEMORY
{
HEAP_MEM : origin = 18000h, length = 08000h
}

SECTIONS
{
.sysmem : { } > HEAP_MEM
}
*****************End Linker Command File*************************

Note that you also have to specify the heap size with the "-heap"
directive.

Anyway, that's where I would start.
--
% Randy Yates % "...the answer lies within your soul
%% Fuquay-Varina, NC % 'cause no one knows which side
%%% 919-577-9882 % the coin will fall."
%%%% <[email protected]> % 'Big Wheels', *Out of the Blue*, ELO
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