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Altera_Forum's avatar
Altera_Forum
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15 years ago

EPCS: Free memory?

Hi all! I have a cyclone2 board including EPCS device. On the cyclone2 i have got a nios2 running. The configuration for the cyclone2 and the software for the nios2 come from the EPCS device. ...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

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From the fpga configuration file (.sof) and the Nios firmware file (.elf) you know exactly the epcs space required.

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While this is mostly true, when using the default bootloader it's not exactly the case. While the software data is stored right after the FPGA configuration bitstream in the EPCS/serial flash device, it is in "boot record" format, not raw binary format.

The tools will generate the "flash/SRecord" data for you using sof2flash, bin2flash, and elf2flash. You can see the size that these SRecords take on flash/epcs by running 
nios2-elf-size <your_elf_flash_filename>.flash

Once you have this information, you should be able to determine where best to place your additional data.

Regards,

slacker