LAUNCHXL-F28379D: CLB help on LUT case

Carlo,

Could you provide me with some more information on this specific example. By "no success" do you mean that the output signal is not lighting up the LED? If the output is not changing after you changed the logic equation, it is possible that you did not properly configured the output crossbar to drive the desired output pin.

Regards,
Peter

Hi Peter , 

no success I mean  that  379D is acting as it a  i0&i1   ( as original example   ) ignoring  mynew  equation !( i0&i1 )   ( I wanted the NOT of the AND ) .

So LED is acting as original example : I just changed the equation by the way  not XBar 

please where am I worng ?

thank you 

bets regards

Carlo

Carlo,

For the logic that acted properly (producing the correct output), did you ever see a signal transition? What I am getting at is that if the logic is outputting a value that is the same as the default state of the pin, it may appear that the logic is working, when the logic is not even connected to the output. I suspect that somewhere between the CLB tile and the pin the connection has not been properly established for the output. There are 2 most likely places - 1) The  Peripheral Signal Mux (if you are using it) and GPIO XBar. Also, you may want to simulate your logic just to verify that you are using the correct tile, LUT, etc.

Regards,

Peter                                                                                                                                                                                                                                                                     

Hi Peter , 

if you start from AND example out of the box  from C2000ware it works  fine   you AND   i0  and i1 .

just change  the  i0&i1   to  !(i0&i1 )  and   you can see no change in output  : it seems CLB tools is ignoring the !  ( the NOT ) 

is the equation "  !(i0&i1) "  correct  ? shoudl I  negate   in a differnet way ?
you should be able to replicate  easily on  379D luanchpad  

regards

Carlo

Carlo,

It is unlikely that the tools are ignoring the "!" as a "not". It is likely that the problem is somewhere down the stream between the CLB and the pad as I have indicated earlier. One way to confirm that would be to force the output to "1" and "0" inside the CLB and watch the pin change state. If it doesn't, this means that ether the CLB Preripheral Signal Mux or the GPIO XBar are configured improperly.

Regards,
Peter

Hi NIma , 

I rechecked my set up and  board and soleved the issue , it was a wring issue on my side 

so 

!(i0 & i1)   is working  as NAND as expected 

thank you very much 

best regards

Carlo

Hi NIma , i  double checked  and found the issue : it was  a bad wire on my launchpad  

so 

!(i0 & i1)    is working properly as a NAND gate 

thank you very much 

best regards

Carlo