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30th November 2019, 00:04 #1
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ATPG stuff, tell me what you think
When ATPG errors

suppose an ATPG errors with slight probability p
p>0
now suppose it is used to calculate untestability of a fault.
Let T be 1 if fault is testable, let T be 0 if fault is untestable.
Now, suppose we use an errorneous ATPG be T OR A, where A = and(x1,x2......x_n)
where n>infinity.
the average <T OR A> for an untestable fault if n>infinity = <T> = 0 in RTG
T = T OR A for exactly for every case except 1 case, for an untestable fault.
Now, T OR A can be solved by deterministic ATPG, T OR A = 1.
<T OR A> = <T> = 0 , is untestable by RTG ATPG. <T OR A> = 0 , therefore has 0 solutions.
Proof
<T OR A> = 1/2^n
no. of solutions = <T OR A> * 2^n = ( 1/2^n )*2^n
= lim episoln1,2>0 n>infinity (1/2^n episoln1+episoln2)*2^n
as n>infinity select episoln1=1/2^n
= (0 +episoln2)*2^n
Select episoln2=0, such that episoln2*2^n =0
= 0
no. of solutions = 0;
T OR A has 1 solution by deterministic ATPG.
Therefore
solutions= 0 = 1
Suppose T is the output T + 0 = T + solutions = T + 1, if T is 0 = 1, if T 0 = = T  solutions = T  1 if T is 1 = 0
untestable is testable, testable is untestable!
Such effects may be heuristically observable.
ATPG will remain unsolved
=================
Suppose a mentally retarded found a solution and
says it is solved, since a mentally retarded found it , it is not solved.

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30th November 2019, 05:27 #2
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Re: ATPG stuff, tell me what you think
Maple finite precision arithmetic errors of the form exists
evalf[4000](limit((evalf[100](limit(1  1/2^n, n = 2000))  1)*2^k, k = 2000)=0
   Updated   
also buffer overflow errors in calculation of 2^n
take program
#include <stdio.h>
int main()
{
unsigned long long x1 = 0;
x1 = ~x1+1;
printf("%lu", x1*x1);
return 0;
}

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30th November 2019, 12:58 #3
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Re: ATPG stuff, tell me what you think
register overflow errors in the calculation of 2^n such as
#include <stdio.h>
int main()
{
unsigned long long x1 = ((unsigned long long )1) << 32;
 hide quoted text 
printf("%lu", x1*x1);
return 0;
}
suresh

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2nd December 2019, 10:19 #4
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Re: ATPG stuff, tell me what you think
what I think is that you are incapable of comprehending how a forum works. you are talking to yourself, mate. and it is not pretty from what I can tell.
Really, I am not Sam.
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