SDRAM Controller on a cyclone dev kit

Aug 15, 2004 2 Replies

Hello,



I've been unsuccessfully trying to use the SDRAM on my MJL Cyclone dev kit. I've tried the example (not very well documented) sold with the dev kit, and tried the Altera IP Sdram controller.



The way i do it : I connect the sdram controller to the sdram and use a small test module to check it reads and writes. I start with the initialisation sequence of the ram (nop for 100µs then load register), i write at the adress 0...00 and then at adress 0..01, read alternatively each adress with a pause and print the output on a digit. At best i have something funny on the digit, which is most of the time not what i want, at worst i have the digit blank.



On the Altera IP, i use the built it pll on clk1 to drive the sdram (since it seems from the specsheets that the output of pll1 is connected to the sdram clk) and either the clk1 or another clk to feed the whole. (i tried at 100 and 33 MHz).



With the MJL Cyclone dev kit i use the pll1 to fee the sdram and the sdram controller.


I've tried to simulate (I use Quartus 4.1) and it seems that the simulation is completly out of its head. I have states transitions BEFORE the signal driving it actually arrives. Are the simulation reliable with the plls ?



Do you please have some idea of what i am doing wrong ?



Thank you very much Nick Charles


Are you trying to access on board SDRAM? Do you know whether you meet your timing for SDRAM? Most of time, that is the case unless your code is wrong. I also have NIOS I Cyclone Dev. board, but didn't get a chance to play with it. Which board do you have?

Kevin

I am trying to access the board SDRAM. I should be meeting the timing of the ram, at least according to the documentation of the sdram controller and the documentation of the ram.

I have the MJL Cycl>Are you trying to access on board SDRAM? Do you know whether you meet your

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