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altfp_add_sub not working on standard Quartus 20.1




I'm using quartus standard version 20.1. I want to use the altfp_add_sub megafunction. However, after generating the megafunction using the MegaWizard Plug-In Manager, when I try to synthesize, I have the error :

Instance "altfp_add_sub_component" instantiates undefined entity "altfp_add_sub". Ensure that required library paths are specified correctly, define the specified entity, or change the instantiation. If this entity represents Intel FPGA or third-party IP, generate the synthesis files for the IP.


I have searched everywhere the solution of this problem in vain. The strange thing is that, on quartus 18.1, I can synthesize. So maybe the megafunction has been removed, but since this megafunction is still available on the IP catalog, I doubt it. 

I also tried to add the component declaration of altfp_add_sub on the altera_mf_components.vhd file but this did not resolve the problem.


Thank you in advance

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3 Replies
Honored Contributor III

What exactly did you name the IP (not called "megafunctions" anymore) in the IP Parameter Editor (Megawizard no longer exists)?  Your instantiation has to match that name exactly.  Post a screenshot of the parameter editor and also show your code for instantiating the IP in your design.  The error indicates a mismatch in how you named the IP and the naming you've used to instantiate it.

To make sure you've instantiated correctly, you can also make use of the _inst.vhd file (instantiation template) file that's generated by the parameter editor.

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Thank you for your answer! I named the IP adder and my instantiation seems to be correct (it matches the _inst file). Moreover, the error is in the adder.vhd file generated by the parameter editor. I'm sorry if I got the words wrong.

I have attached a screenshot of the instantiation of the IP in my code as well as the adder_inst.vhd and adder.vhd generated by the parameter editor.


Thank you

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Have you upgrade the IP when migrate to the latest Quartus version?  
Try to rebuild the project to check if the issue persists. Also check that the device used is supported in the document below.


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