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Altera_Forum
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15 years ago

Changing the bootloader HEX file in the NIOS II IDE

This is with NIOS II 8.1 although I'll be moving to 10.1 and will need to do this: I'm trying to use a custom bootloader (loaded in EPCS) without changing the hardware (in SOPC Builder). The r...
Altera_Forum's avatar
Altera_Forum
Icon for Honored Contributor rankHonored Contributor
15 years ago

Thanks. I think where I went wrong is my assumption that the EPCS bootloader is loaded like onchip memory. It's not and must be part of the hardware (SOF) information. The memory (512 bytes) where the EPCS module is located is not read/write. Therefore, it is not loaded by the data in the .flash file created by the NIOS II tools. I thought it was added to the .flash at this time but it appears to be in the SOF to begin with.

I suspect if you want to include the bootloader in the application (specifying an onchip RAM section for it's location) then you could point the reset vector to this onchip RAM section. I'm not the hardware builder here so I can't test it. It might be nice to know if this works. Then the RAM used by the bootloader could then be reused by the application once it's up and running.

Bill