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No PLL output on modelsim

Altera_Forum
Honored Contributor II
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Hi all,  

I am using quartus 2 9.1 sp2. I want to run an ALTPLL considering only one input (Clk) and two output ( c0 and locked output). I have generated the vhdl file for modelsim. I simulate it with 50MHz clock and i see no output on both the output signals. Please see the files below for .bdf and modelsim screenshot. Please help me how to see the output and what changes i need to make.  

 

Thank you 

Ash
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Altera_Forum
Honored Contributor II
3,834 Views

do you think the input-clock is 50MHz?

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Altera_Forum
Honored Contributor II
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Hi Ash, 

 

Just to check with you if the pll_locked got asserted? Can you try to apply a reset to the PLL?
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Altera_Forum
Honored Contributor II
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yea that's what i have designed in Mega wizard plug in manager. I have chosen 50MHz for the input clock

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Altera_Forum
Honored Contributor II
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Hi akira, 

yea that's what i have designed in Mega wizard plug in manager. I have chosen 50MHz for the input clock 

Thanks
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Altera_Forum
Honored Contributor II
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Hi tiny007,  

I added a reset as per what you said. still the output remains the same Undefined. Is there somewhere i am going wrong?
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Altera_Forum
Honored Contributor II
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Hi amod, 

 

Two things: you only show 5-6 ns on your waveforms, the PLL models, like real PLLs, take some time to initialize and sync before you get an output. 6ns is not nearly enough time. I forget how long this takes in simulation (I think it's a lot less than for the real devices) but give it a us or so before you give up. Second, it looks like the clock you're feeding it is NOT 50MHz, but 10GHz! The period shown is 0.1ns, check your clock generation. 

 

-Fred
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Altera_Forum
Honored Contributor II
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FredH is right. Where is your testbench? Post it here.

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Altera_Forum
Honored Contributor II
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Hi FredH i have changed the clock period to 0.02 us and run the simulation for half a second. still my output remains the same. Please see the attachment.  

Thanks  

Ash
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Altera_Forum
Honored Contributor II
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Hi krasner,  

 

Could you please explain me how to generate testbench ?
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Altera_Forum
Honored Contributor II
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Are you getting any warning when you run modelsim? Perhaps a library is not set up. See this thread: http://www.alteraforum.com/forum/showthread.php?t=21634

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Altera_Forum
Honored Contributor II
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A testbench is simply a verilog or vhdl script where you set up you input signals to the system that you are simulating. Usually, you would write one by hand. 

 

How did you set up the input clock signal to your pll system?
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Altera_Forum
Honored Contributor II
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yea there is and its Warning: (vsim-3473) Component instance "b2v_inst : altpll0" is not bound.

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Altera_Forum
Honored Contributor II
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ok my input clock signal is the input pin clk1 in the bdf file 50MHz. if i look into ppl1.vhd file. i dont have altera_mf header file. Can this be the problem ?

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Altera_Forum
Honored Contributor II
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OK this means you are missing the pll library. Make sure you are including all the altera libraries in your modelsim environment.

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Altera_Forum
Honored Contributor II
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ok i found out that. Is there a way do that ? Can you direct me here please? I need to get this work.

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Altera_Forum
Honored Contributor II
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Yup. you have to include the altera_mf library

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Altera_Forum
Honored Contributor II
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It should me under C:/altera/modelsim_ase/altera/<vhdl or verilog>/altera_mf 

 

You have to provide that path
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Altera_Forum
Honored Contributor II
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This is a screenshot of the library panel in the modelsim. This contains altera_mf library. But in the vhdl file i dont have altera_mf libary. Please see the screenshots.

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Altera_Forum
Honored Contributor II
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posting the attachments again.

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Altera_Forum
Honored Contributor II
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In your vhdl file try including LIBRARY altera_mf; 

USE altera_mf.all;
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