Problem with SDRAM

If the jtag code download verifies ok (also check the sizes and addresses) them maybe you've forgotten to give the instruction master access to the sdram!

Also verify that the sopc generate - quartos build - fpga download sequence is working properly after your sopc updates.

The ide should force you to regenerate the BSP, then clean + compile everything.

The ide 'run' is then likely to object to the version of the fpga image, it seems to cache the fpga version and needs manual prodding.

I also found it seemed to run the old code (from sdram) then download and run the new version.

I couldn't find a way of getting the ide to just do a sopc reset, code download, and execute. Not without it running make and asking questions about how you wnt to run the program (again).