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Setting up a 25Mhz PLL

Altera_Forum
Honored Contributor II
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Hi, 

 

I have a PCIe Stratix II dev Kit. I need a 25Mhz clk out. My understanding is that the FPGA can provide a clock out (using the 100 MHz on board internal clock) by setting up a PLL. If this is correct, how do I go about doing it.?  

I have no idea on how to set it up. Any help will be appreciated. 

 

Thanks in advance.
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Altera_Forum
Honored Contributor II
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You need to create an ALTPLL instance that will create a PLL in your design. The PLL will accept your 100MHz clock as input and produce a 25MHz clock as output. 

 

From Quartus II: 

1 - Tools->MegaWizard Plug-In Manager. 

2 -Create a new custom megafunction variation. 

3 - Select the I/O category on the left. 

4 - Then select the ALTPLL megafunction. 

5 - Give your file a name and click next. The megawizard will launch. Read the documentation if you need to. At the end of the day you'll have a verilog or vhdl module that you can instantiate in your design. 

 

Jake
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