I must admit it's been a while since i have used Spartan2E; please help me with relatively simple issue, as i cannot find the answer to my question anywhere.
I am given a board, where I have XC2S400E device (FT256 package), and I have to make a design with what I have. I would like to use DLL. That is, I have an onboard oscillator of 25 MHz, which I would like to multiply by 2, and get 50 MHz (so fat, per datasheet DLL can accept a frequnecy starting from 25 MHz). FPGA device does not receive any external reset (do not ask why, I did not design the board).
Now, the question. I see that CLK2x output generates 25 MHz, not 50 MHz. Do I have to reset DLL??? It's just that before I ask to solder some wire for reset, I would like to be sure of that.
I saw in Virtex-II devices many times that there is no need for resetting DCMs, and the frequency they produce is just fine.
Thanks a lot in advance.