Hi I have done a SDRAM controller design in spartan. using Micron SDRAM(128Mx32 with 4 banks).
If I access SDRAM using address lines sdr_A8 to sdr_A0, I am able to access one row 100% correct without error. My problem starts if I connect sdr_A11, sdr_A10, sdr_A9. Board hangs. I am not able to detect the board. Some how I used a tristate buffer for sdr_A10 (which is not the way to do so, but still I just gave a try) to precharge the rows, obviously I am not reading correct data from few rows since I have not connected sdr_A11 and sdr_A9. Using tirstate buffers for these llines also didn't help. I couln't trace where the problem could be. If anyone came accross such problem anywhere in your design experience (not neccessarily in SDRAM) Please help me.
Thanks Mohni.