who can help look at this problem?

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Error: Symbolic name "extclkena3" must be port of megafunction, macrofunction, primitive, or state machine "pll"

Warning: Symbolic name "extclkena" is used but not defined as a group -- attempted to use existing nodes

Error: Symbolic name "extclkena2" must be port of megafunction, macrofunction, primitive, or state machine "pll"

Warning: Symbolic name "extclkena" is used but not defined as a group -- attempted to use existing nodes

Error: Symbolic name "extclkena1" must be port of megafunction, macrofunction, primitive, or state machine "pll"

Warning: Symbolic name "extclkena" is used but not defined as a group -- attempted to use existing nodes

Error: Symbolic name "extclkena0" must be port of megafunction, macrofunction, primitive, or state machine "pll"

Error: Can't elaborate user hierarchy "nios2_sys:inst|pll:the_pll|altpllpll:the_pll|altpll:altpll_component"

Error: Quartus II Analysis & Synthesis was unsuccessful. 5 errors, 30 warnings

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it seems be some problem on PLL,but i don't know how to solve it.

by the way, i use a pll generate two clocks: sys_clk and sdram_clk, the sys_clk's phsae shift is 270 deg and the sdram_clk's phase shift is (270-60.75) deg.

please help me. thanks! http://forum.niosforum.com/work2/style_emoticons/<#EMO_DIR#>/smile.gif