max10 on chip flash read/write in nios

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Hi,

Have you try to erase before write? Typical CPLD and flash require erase operation before write. Thus you need to disable write protect and erase first before write to UFM1. Try setting CSR to 0x001fffff or 0xff1fffff to disable write protect and erase for UFM1.

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thank you very much! i stuck in this problem for 2 weeks!

i erase the UFM1, then the wrie success.

then i repower the board, and write to the UFM1 without erase, and it success too.

so it seems like the UFM only should be eased at the first time,.

thanks!