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Altera_Forum
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11 years ago

DDR3 SDRAM controller - pll_ref_clk

Hi, I am using Quartus 13.1 and DDR3 SDRAM controller with hard memory controller enabled in the QSYS. The DDR3 controller's PLL reference clock frequency is set to 125Mhz and I was using a clo...
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Altera_Forum
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11 years ago

Hello NJ_paddler, here are a couple of things to try. Here is the link to your error from Altera's website:

http://www.altera.com/support/kdb/solutions/rd05282014_665.html

First try the approach that they give on that link. If that doesn't work, I know that I have had issues in placing PLL's in the past. The way that I have got around it in the past is by implementing an altclkctrl megafunction placed in between the clocked input pin and the PLL as seen in this link:

http://www.altera.com/support/kdb/solutions/rd03302012_430.html

Best of luck to you! Let me know if neither of those approaches work.