DSY_SDRAM_DATA stored in SRAM

Software Development
1

I just noticed that DSY_SDRAM_DATA seems to not store in SDRAM, it just stores it in SRAM. I’m implementing a FIR filter and storing a bunch of IR arrays. If I do something like:

float DSY_SDRAM_DATA ir_flat[] = {1,2,3....};

it ends up identical to:

float ir_flat[] = {1,2,3....};

if I do

float DSY_SDRAM_BSS ir_flat[] = {1,2,3....};

it is properly allocated in sdram space (though of course not initialized)

ir_flat is a global variable.

Any ideas on this?
Thanks!

2

You should take a look at this comment

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3

Close, but I’m loading from QSPIFLASH (tried the hack subbing “> QSPIFLASH” for “> FLASH” in the linker, and the usage info looks correct, but it doesn’t initialize the data properly (or at all).

4

.data section is filled in startup file, so you would have to do the same for variables used in SDRAM section. I.e. add a copy of that section using _esdram in place of _edata and so on.

This obviously can work if SDRAM is already initialized, which can only be done if bootloader did it as firmware can do it only at a later time when main() gets called.

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5

Ah, that did it! Thank you! Maybe this should be part of the next release.

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