CLD-R

[tbob]

I went through the practice CLD-R exam and have a couple of questions.  Perhaps someone could answer them:

One question is as follows:

Which of the following statements about events is true?

  a.  The timeout even causes an event to fire every x ms where x is the value wired to the timeout terminal.

  b.  some false answer

  c.  some false answer

  d.  When processing a filter event, wiring a corresponding terminal from the Event Data Node to the Event Filter Node has the same effect as leaving the Event Filter Node unwired.

The answer is given as D.  However, I believe the correct answer is A.  Why am I wrong?

Another question:

User created custom probes will have which of the following?

 a. Input: Datatype of the wire.  Output: Same datatype

 b. Input: Datatype of the wire.  Output: Custom output

 c. Input: Datatype fo the wire.  Output: Boolean

 d. Input: Boolean  Output: Numeric

The answer is given as C, but I believe it should be A.  Custom probes allow you set a condition and it pauses on that condition.  But the output is the same datatype as the input.  Isn't this true?

[Darin.K]

The next custom probe I create will be the first, but in regards to the first question I would say that d is certainly a true statement.

The smart-alec in me says that wiring a value of -1 to the Timeout does not fire an event every -1 msec.

The serious side says that the Timeout event only fires when NO OTHER event fires for x msec.  In this case a is true only when there are no other events firing.

[tbob]

---

@Darin.K wrote:

The smart-alec in me says that wiring a value of -1 to the Timeout does not fire an event every -1 msec.

The serious side says that the Timeout event only fires when NO OTHER event fires for x msec.  In this case a is true only when there are no other events firing.

---

I consider this a trick question.  Sure a is not always true, but the question was designed to purposely fool the person who didn't think it out 1000%.  I looked at a and stopped reading because it fit the definition of timeout.  Shame on NI.

[Ray.R]

I hate to say it, but Darin is right..  in both cases...

(not that I hate saying that Darin is right, 'cause ..  well I can't remember ever seeing a pst where he was wrong 😉

But I do agree that it is a bit of a trick question that I would have missed.  So don't feel bad. 

[tbob]

Does anyone have any comments about the custom probe question?  I created one on a numeric wire, and the output is numeric, not boolean.  Why is the given answer the one with a boolean output?

[smercurio_fc]

I just love standardized tests like that.

As for the custom probe question, I think the tricky part is whether you're creating a custom probe via Custom Probe >> Generic or via Custom Probe >> New ...

For the latter you basically get a VI that has a Boolean and String output.

I actually have a question: What's a CLD-R? Is that like the read-only version of CLD?

[tbob]

CLD-R is CLD Recertification.  We have to take this stupid standardized exam with trick questions every 2 years so that NI can pocket $200 a pop.  The trick questions are there in hopes that some will fail and have to retake the test for another $200.  I'm being sarcastic because I believe that the recertification should be every 5 years at the least.  Also, all of the questions should be straight forward without resorting to trickiness.  Every answer should be very obvious to an experienced Labview programmer.

The question did not make clear what type of custom probe was to be created.  I just created a custom probe - new on a numeric wire.  The probe watch window has a numeric, same data type as the wire.  So the obvious answer is A.  But if you look at the vi that is created, it has a HIDDEN boolean output and a HIDDEN string output.  So answer C is an obvious resort to trickery and is not even fully correct since there is also a string output.  But the boolean and string are outputs of the vi, not the probe watch window.  When people think of probes, they think of what is displayed on the screen, the probe watch window.  It has the same data type as the input. 

Come on NI.  There is absolutely no need for this kind of BS trickery.  It just shows how underhanded you can go to collect money.

[MarkMoss]

---

@tbob wrote:

One question is as follows:

Which of the following statements about events is true?

  a.  The timeout even causes an event to fire every x ms where x is the value wired to the timeout terminal.

  b.  some false answer

  c.  some false answer

  d.  When processing a filter event, wiring a corresponding terminal from the Event Data Node to the Event Filter Node has the same effect as leaving the Event Filter Node unwired.

The answer is given as D.  However, I believe the correct answer is A.  Why am I wrong?

---

IMHO, the practical reason why A is false is that the timeout event case will only execute after there have been no other events for x ms.  Any time another event occurs, the time restarts, so the timeout event will only occur every x seconds when there are no other events.  In fact, if you have another event that occurs periodically with a period of less than x ms, your timeout event case will never run.

Mark Moss
Electrical Validation Engineer
GHSP

[tbob]

---

@MarkMoss wrote:

IMHO, the practical reason why A is false is that the timeout event case will only execute after there have been no other events for x ms.  Any time another event occurs, the time restarts, so the timeout event will only occur every x seconds when there are no other events.  In fact, if you have another event that occurs periodically with a period of less than x ms, your timeout event case will never run.

---

Mark, Darrin K has already stated that fact and I agree.  What I'm most concerned with is the 2nd question and NI's obvious resort to trickery.

[Broken_Arrow]

tbob,

Why would you take a CLD-R but show a logo in your signature for CLAD ?