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Altera_Forum
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10 years ago

How to enforce the used DATA input of a LUT?

Hi, I am implementing a Physically Uncloneable Function with Ring-Oscillators (RO) on Cyclone IV FPGAs. Each RO consists of 16 LCELLs, placed in the 16 LEs (i.e. LUTs) of another LAB. With...
Altera_Forum's avatar
Altera_Forum
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10 years ago

Thanks for the quick reply. My interest is purely research related at the moment!

I know about the back-annotation feature. This allows me to fix the changes I manually make to the rounting. However, to get these changes in the first place, I still have to go through the process I just described in my other post here http://www.alteraforum.com/forum/showthread.php?t=48732, right?

This is not really viable. Imagine I want to implement ROs in ALL LABs of the Cyclone IV to see if there are manufacturing caused biases. An then I might even want to play around to see the effects of using deliberately using different LUT data inputs. This cannot be done by hand (not even by one of my students... ;-)

But maybe, instead of having script create the changes.tcl file for me (as suggested in my other post), I could build a script to modify or create the .rcf file, as you suggested. I will have a look at this.

Thanks again.

UPDATE: On second thought, the rcf-file includes ALL routing, regardless of whether it is the compiler's original choice or already customized. So it should be possible to have a script crawl through the rcf-file and make the appropriate changes! Will definitely give that a try now!