--- Quote Start ---
Any other idea to try?
--- Quote End ---
How about tracing the SPI flash sequence? The only thing I can guess is that perhaps your 1G flash is not responding correctly, eg., perhaps your NIOS II software is in fact "smarter" than the Cyclone V configuration manager, in that you are using 4-byte addressing when programming and reading, but the Cyclone V is not, and its only issuing 3-byte addresses ...
Do you have a logic analyzer, or another FPGA board that you can instantiate a SignalTap II instance, and the skill to solder some wires onto the SPI flash pins (unless of course you have a 10-pin AS header you can use directly)?
That would be what I'd try next ...
Cheers,
Dave
Honored Contributor
