Suspected problem "BUG" with ENOR generic logic models supplied with MultiSim

[Sparky44]

Greetings,

I am currently using version 10.0.343 and encountered a possible issue with the ENOR/EOR (Exclusive NOR and OR) generic logic models provided in the master database.  Specifically I attempted to use the ENOR5 model and experienced unusual results.  I did try the 3 input generic with the same results, but have not tried all the generic exclusive xxx models.

The problem I have found relates to the models operation.  For example, with all high or all low inputs to the ENOR5, you would expect a high output, but that is only achieved with all the inputs low.  The following is a truth table using the ENOR5:

Inputs        Output

L L L L L    H

H L L L L   L

H H L L L   H

H H H L L  L

H H H H L  H

H H H H H  L

The model description includes a "TIL" reference.  I was not able to locate specifics on that so as to provide a possible explanation (i.e. fuzzy logic or otherwise).

74 series exclusive NOR and OR's appear to work fine.  In my particuar project I needed a 5 input XNOR, but was able to work around this issue by compounding two input XNOR's and AND gates.

Please let us know what you find.

Sincerely,

Sparky

[Sparky44]

All,

The "suspected" bug turns out to be no more than that.  As it turns out, TIL (Technology Independent Logic) does react differently than traditional logic.  So, if not already aware, be aware as you might find yourself in the same situation I found myself in.

Thanks for your help Max!