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marcorig's avatar
marcorig
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9 months ago

LPM DIVIDE behaves differently between simulation and implementation

I have implemented a divider in a custom VHDL module in order to replace the instances of the LPM_DIVIDE IPs in my project. I've then checked the functionality of my module against the LPM_DIVIDE and...
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Simulation
marcorig's avatar
marcorig
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9 months ago

Hi Sheng,

thank you very much for the detailed information about the IP’s functionality. However, in my opinion, the issue of the mismatch between simulation and implementation cannot be considered resolved, as I would like to understand:

  1. Where is it stated in Altera's documentation that using the parameter LPM_HINT => "UNUSED" is incorrect, as you mentioned?
  2. If LPM_HINT => "UNUSED" is incorrect, why is it assigned as the default value in the module declaration inside lpm_pack.vhd?

To truly resolve the issue and prevent it from occurring in the future for other users, I believe that the simulation model of LPM_DIVIDE should be updated so that the behavior in simulation matches the implemented behavior, regardless of the value of the LPM_HINT parameter.

Regards,

Marco.