Nios II Flash Programmer with 8-bit CFI Interface

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I am having a similar problem. I have a system with:

UART (RS-232) + NIOS + ON-CHIP RAM, C program runs OK

UART (RS-232) + NIOS + ON-CHIP RAM + DDR, get "leaving processor paused" problem.

It does appear like a timing-related issue but I cannot find a proper .sdc generated by SOPC builder for the first case to improve on. What I see in the first case is that the clock frequency is set to 1 GHz as all clocks are (as if proper clock constraints are missing) through I set in SOPC builder the frequency of the input clock to the system to 144 MHz.

The first case appears to work because it is a simple system.

The second case with DDR appears to fail because the NIOS is now constrained differently.

cpu.sdc does not contain any clock frequencies.

I am using Quartus II 8.0 and NIOS 8.0 on Linux with OpenCore Plus evaluation mode.

Any information would be appreciated.

RAUL

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Found out that the problem was a hanging NIOS reset_n pin. Once NIOS is properly reset the processor can be downloaded reliably.