Running program in SDRAM

redsun,

> What may cause such problem?

There are many potential causes. Here are some:

- SDRAM was not placed correctly (shorts/opens on pads).

- Bad traces between Cyclone and SDRAM.

- SDRAM clock doesn't meet timing requirements.

- Pins are not assigned correctly.

- SDRAM timing parameters are incorrect.

- SDRAM is not actually mapped to 0080_0000.

Check the easy stuff first (pin assignment, timing parms, base addrs) first. The check

your timing analyzer results against your board layout -- you may need to shift your

SDRAM clock phase.

Finally, break out a scope and add an SDRAM memory test to your hello_world that runs

out of on chip ram Make sure you bypass/don't implement the data cache.

Regards,

--Scott