DDR2 HPCII control signal always low

I everybody!

I am using a development kit with CycloneIII and I need to use the DDR2 memory. I try to read and write using the HPCII.

When I program the FPGA and give the read/write command, control signals rasn, casn, cke, wen stay always low and no read o write are performed.

Anybody have some advice?

Also, I cannot well understand the function of the "local_size" and "local_be" signlas.

Thanks all!!!