\_\_\_Hi, everyone. I have instantiated a `PLL` using the Megawizard in Quartus II. Then I wanted to simulate it using `ModelSim SE` because Quartus II 10.1 doesn't have a built-in simulator. I copied *builtInPLL.vhd* (output of the Megawizard) and *PLL\_tb.vhd* (testbench) to the directory of the ModelSim project. But when I compiled *builtInPLL.vhd*, it gave out the following error messages:

> 
> Error: builtInPLL.vhd(39): Library altera\_mf not found.  
> 
>  Error: builtInPLL.vhd(40): (vcom-1136) Unknown identifier "altera\_mf".
> 
> 
> 

relevant lines in *builtInPLL.vhd*: 

> 
> LIBRARY altera\_mf;  
> 
>  USE altera\_mf.all;
> 
> 
> 

I googled these messages but found nothing really helpful. I copied *altera\_mf.vhd* from `..\eda\sim_lib` and compiled it with *builtInPLL.vhd*. Modelsim still gave me the messages above. And many files with suffix `.dat` and `.dbs` were created in the work directory. What are they?

Where is the library `altera_mf` located? And how can I simulate a megafunction using ModelSim SE.  

Any help will be appreciated.Thanks.