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Need to expand SigmaStudio State C beyond 9999999 bytes

Question asked by rsmith@iedaudio on Dec 12, 2016
Latest reply on Dec 14, 2016 by TylerK

Hello,

 

We are developing a product using SigmaStudio 3.12 for SHARC and the 21489 DSP.

We are planning on using an external SD RAM (512MB) for a pooled audio delay.

 

Here is an earlier thread: Running Pooled Delay Module on SDRAM (state C) Memory 

 

We have had a requirement change since then, and now are planning on using (up to 12) ~30 second delay lines.

At 48K sampling x 30 seconds x 4 bytes per sample this means we need 5760000 bytes per delay line (or 5.49 MB or 1.37 M words ).

 

Of course we need to map more external memory as well as expand the delay block size... and I have been able to build blocks that can produce a full 30seconds of delay. 

To add more than one delay we had to expand the memory in the linker description (did that) as well as the range in the loader (did that).

 

However, we have run into an unexpected problem with SigmaStudio...

When increasing the size of the 32 Bit State C Memory, the dialog box does not allow setting any amount beyond a 7 digit number (ie 9999999).  This seems like an artificial limitation, since the DSP, linker, and ldr can all be set up to address memory well beyond this range.  Because of this limit, I can only reserve enough memory for one 30 second delay block to run (since I reserve 5760000 bytes for each block)- but not room to expand for more blocks (even though the hardware should support it).  This seems strange because with this limit you cannot even access the full memory supplied with the EZ Kit (32MB).  This limit feels like a dialog box "range" limit.

 

What can be done to relax this limit or is there a way to work around it?

 

Current Toolchain:

CCES: 2.3.0.0

SigmaStudio 3.12 Build 1

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