So we have already seen the operators and or an intersect and this lecture provides a few more nuances on the same. Firstly, I'm showing these examples with very simple sub sequences. But you may replace this with much more complex sub sequences. And this concepts will be of use with those complex sub sequences. So here's a property where z with overlapping implication implies that ABCD should hold and ABCD is an intersection of A B and C, D. and a B says that B must follow everything five blocks, and here C, D and E. Each has a temporal domain of two clocks. So let's look at this example first, as required when z is Rule A B and C D should start at the same time because of the overlapping operator and that should now be arrives within one to five blocks that is also true and CD also follows the requirements.
So, that is also true, but intersect requires that both a B and C D and at the same time and they do not. So, it will go back and fill the property when the first subsequence is not true. Similarly, here we can see that z CNA started the same time, but, and we arrived 1234 and on the fifth clock that is also true, and C D is also true, but because they don't and at the same time the property will fail. The shorter sequence. Now in this case, I have shown the same sequence. But I'm simply saying that a 1234 b arrives within five clocks.
And C D E also follows its requirements and is both and at the same time that the property will pass at the end. So, here's an example to make a point. Here, the ABC sequence has fixed time delay, and so does CDE. So will this property ever pass? No, it won't, because these two properties very clearly show that they never end at the same time. So the point is that it makes sense to use intersect with sub sequences with ranges when you have a range.
Is there's a good chance that the two properties manned at the same time, as we saw in the previous example. Now, here's a very interesting application that I consider as an idea generator. So the specification says that data it goes high within four crops after the rising edge of reach. Now, first off the bat, this is a very simple specification to model. So you can simply say at positive clock dollar rose retry implies that we didn't want to fall close our clocks, data rate should go high. And that's it.
If the data did goes high in the fifth clock, then the property will fade. I'm doing the same thing with a much more complex way. And you may wonder why, but I will tell you that it is an idea generator. So again, dollar rows retry there are two steps Frequency This is one and this is another. So, this subsequence Is that true will remain true. Consequently, from one to four clocks.
And this subsequence is that when retries true, we don't know when so from one clock to forever dollar rows or data does that mean data rate can go high anytime after retry has been found to be true. Now let's say that data arrives in the fifth clock. So this sequence will end on the fifth clock. But since this sequence subsequence is true only for four crowds, it ends after four Gox. So then these two sequences do not end at the same time and the property will fail as required. But let's say data rate arrived in the third clock.
So, this sequence a will and on the third clock, while this sequence will also end on the third clock because it is true for one to four clocks on the third clock it is true. So, both sequences are true in the third clock and the property will pass as required. So, as I say, this is an idea generator whenever you want to restrict a very complex subsequence for within a given time frame, then you may use this particular approach as I've shown in one of the lectures. I use this concept to model variable delay where the delays are required to be always constant. They are operator simple sequences again Same property and sequences, where z A and z must be true at the same time which they are, but we must follow after two clouds it does not. So, AB sequence fails.
So, the simulator will continue to look for the other sequence to be true because this is an or and CD he does meet his requirements. So, the property will pass here at the larger sequence. And here A and B has a correct relationship and so, the C D and E, but the property will pass as soon as a B is true because this is an order, it will not care to see what happens to c d. So, the property will pass as soon as one of the two sequence is true. In this case, the problem is right off the bat Where z A and z must start at the same time because of the overlapping operator, but a B does not start when a does not arrive the same time as z. So, AB fades, but the simulator will continue to look for CD E to be true and it is indeed true.
So, the property will pass here and in this case z A and z arrive at the same time as required, but b does not arrive after two clocks. So, he fails and in CDE sequence he never arrives as required to cross after d. So, it also fails. So, both sub sequences fail and the or will fail on this clock. And this is yet another example where there is a range in sequence AB Content delays in CDE. So Z and Z arrive at the same time as required. But B does not arrive even after five Crocs, but CDE does meet this requirement.
So the property passes. Now here, B does not arrive even after five clogs, and c d c did not arrive the same time is z as required by the overlapping operator. So, CD also fails, and both sequences fail and the property fails here. So, that's pretty much it a simple lecture. Again, the sequences or sub sequences that I have used are very simple, but this concept will come in use when you have complex sequences to deal with. So, thank you