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21618 Diskussionen

Cyclone V LVDS differential termination

Altera_Forum
Geehrter Beitragender II
1.860Aufrufe

In the pin planner I specified input termination as differential for LVDS inputs. 

Do I need to specify for both positive and negative signals or just one? 

It seems to work both ways which bothers me. 

 

Thanks
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3 Antworten
Altera_Forum
Geehrter Beitragender II
671Aufrufe

you may check the fit report for those two ways

Altera_Forum
Geehrter Beitragender II
671Aufrufe

 

--- Quote Start ---  

you may check the fit report for those two ways 

--- Quote End ---  

 

 

Looks like that helped. 

If I only assign termination to the positive then both positive and negative termination are off in the fitter report. 

So it appears you have to assign termination to both positive and negative in the pin planner. 

 

Thanks
Altera_Forum
Geehrter Beitragender II
671Aufrufe

Sounds unlikely. Up to now, the basic method with differential I/O standards has been to assign the non-inverted pin and also specifiy additional I/O features for thi spin. 

 

The pin planner tool is primarly a wrapper around the pin assignments, but does some things on it's own by e.g. displaying the inverted pins along with the (primarly assigned) non-inverted pins. 

 

In case of doubt, I would check the actual pin assignments, in assignment editor or *.qsf file.
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