What is QUARTUS_CREATED_GND? Can I get rid of it?

[Heiko]

As part of a school project I was implementing a very large combinational logic circuit on a CycloneV (5CGXFC7C7F23C8). And printing the logic blocks that were instantiated using the command `get_nodes -type lcell` and I noticed that one of the LABCELLs was always used by "~QUARTUS_CREATED_GND~I".

I can't find what this is in any of the documentation or on any other questions online.

So, it's sparked my curiosity.

What is the QUARTUS_CREATED_GND? What does it do?

If it serves no purpose, is there a setting that removes it? Seems like it is just using up a LAB for no apparent reason.

Thank you!

[Nurina · Accepted solution]

Hi,

QUARTUS_CREATED_GND is an auto-generated ground pin/signal/port created by Quartus. You cannot modify this pin.

The point of this pin is for the tool to create a logic 0. It has to use a LUT with a LUT-mask such that it always generates a logic 0 and then routes this to where it is needed rather than using additional LUTs to create local 0s.

Regards,
Nurina

PS: If you find any comment from the community or Intel Support to be helpful, feel free to give Kudos.

[Nurina]

Hi, 

I’m glad that your question has been addressed, I now transition this thread to community support. If you have a new question, feel free to open a new thread to get the support from Intel experts. Otherwise, the community users will continue to help you on this thread. Thank you.

Regards,
Nurina

PS: If you find any comment from the community or Intel Support to be helpful, feel free to give Kudos.