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Honored Contributor
Honored Contributorcustom Nios bootloader
Hello, I have a very small board containing ethernet phy, sdram and cyclone III fpga only. The fpga upload is done from another board, which has microcontroller on it, using passive serial mode. T...
Altera_ForumHonored Contributor
Honored ContributorSorry for taking an old thread up, but I am stuck on some interesting place.
Now I am trying to do a bootloader, which gets data through SPI. The bootloader reset vector is in on-chip memory, which is at 0x01000000. The exception vector is placed on SDRAM, which is at 0x00800020 (SDRAM component address is 0x00800000). Now when I try to write the binary data to SDRAM_BASE (0x00800000) or to exception address (0x00800020), then the data is written up to a certain address (e.g. writes up to 0x00800864) and the cpu hangs. If I begin to write from 0x008F0000, then all the binary data is written fine. The question: where do I have begin to to write the binary data? To SDRAM_BASE, to exception address or other address?
