How can I found which point are stuck?

[u24c02]

Hi.
What if we have the following logic
F=(a+b)(c+d) also F=(ab)+(cd)

What if c is stuck 0 or 1 the can we found which point are stuck?

 

[ads-ee]

This looks like a homework problem.

Use logic to figure out what happens if c is stuck at either 0 or 1.

stuck at 0:
F = (a+b)(0+d) is the same as F = (a+b)(d), so your truth table will be different from your original logic.

I'll leave it up to you to figure out what the stuck at 1 condition looks like and the ones for F=(ab)+(cd)

 

[u24c02]

This looks like a homework problem.

Use logic to figure out what happens if c is stuck at either 0 or 1.

stuck at 0:
F = (a+b)(0+d) is the same as F = (a+b)(d), so your truth table will be different from your original logic.

I'll leave it up to you to figure out what the stuck at 1 condition looks like and the ones for F=(ab)+(cd)

Currently I'm looking at TetraMax manual. But I can hardly understand how it can find faults. I heard that it use D algorithm but it does not make sense to me. So I was asking it.

Anyway, can I found this where the stuck happen exactly? Not just fault existed.

 

[kam1787]

Hi.
What if we have the following logic

F=(a+b)(c+d)

also F=(ab)+(cd)

What if c is stuck 0 or 1 the can we found which point are stuck?

do not understand what you mean...................

 

[u24c02]

What if it has stuck at c as 0 or 1, then can we find where the stuck happen?

- - - Updated - - -

Update :

What if it has stuck at c as 0 or 1, then can we find where the stuck happen? If yes, how can we find where the stuck happen?

 

[kam1787]

lacking context [what platform, what language, what code, what compiler, etc] ....................

 

[FvM]

can we find where the stuck happen?

I must confess that I don't understand the meaning of "where the stuck happen"(s) in terms of digital logic. I expected a problem like ads-ee discussed, but apparently the question is about something different.

 

[harpv]

I believe your task here is to figure out the test vectors which when applied as input to the function will determine whether c is the point having fault and if so, is the fault stuck at 0 or 1. This is what precisely ads-ee also mentioned, so you can follow his instructions to get the vectors.

It is possible that a single vector detects faults at different nodes. So you may need more than one vector to distinctly identify the origin of the fault. For e.g. in your function, one vector may detect c stuck at 0 as well as a stuck at 0. So list down all the vectors and try to find that unique vector.

D algorithm you mentioned is used by the tool to generate these test patterns as far as I know. I'm not sure if there'll be any mention of it in the tool manual though. You can use the algorithm to generate the input vectors you need to detect all the faults.

 

[u24c02]

[Moved]Calculating stuck at fault.

Hi.

Now I'm trying to find a test vector as follows,
F= (ab)+(cd)
Would you please let me know If the B is SA1, how can I use vector to detect B's SA1?

I 'd calculate like this A=1, B=0, C=0, D=0 , Is this right?