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CFI flash 512Mbit access

Honored Contributor II



I want to test the flash memory (Intel 512P30) on my board with the NIOSII. 


In Qsys, I instantiated a "Generic Tri-State Controller" with the "Intel 256P30" preset, I increased the address to 26 bits and the CMacro.SIZE to 67108864u. 

I can read/write the flash memory but only the first 256Mbit... It's the same with the NIOS Flash Programmer, it only see a 256Mbit memory from the CFI table... 

Is it because there are 2 dies in one chip, each die don't know there is another die in the chip? In Qsys, do I have to instantiate 2x 256Mbit flash, with different base address, instead of 1x512Mbit? 

I think the missing address bit will be "flash0_select_n" and the new nChipEnable will be "flash0_select_n AND flash1_select_n". 


Thanks for you help.
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Honored Contributor II

According to the flash memory datasheet, you select either die with the A25 address line. 

Then you probably have a problem with byte / word addressing