I ran into a possible bug that I'd like to get some feed back on. Attached is a sequence and VI that when run in test UUT every other iterations value for the step (i.e. next UUT) the result is maintained from the last UUT and it show up in the report. Iit is a stripped-down-to-nothing version from the acutal test sequence on the floor with some stuff to simulate the error.The step does have the ignore error on and this situation happens when an error occurs but I would not expect the previous test result value to show up. Run the sequence and see what I mean. It generated a report that makes my manufacturing floor question the stability of TS. PS. LV 8.5 TS 4.0 Message Edited by paulmw on 03-04-2009 12:31 PM

Paul -The reason are getting failed with a measurement from the last good UUT is because of many compounding issues. The sequence has the default setting of "Optimize non-reentrant calls to this sequence", which basically tells TestStand to cache the runtime copy of the steps in this sequence to improve performance for each subsequent call to the sequence. So the Step.Result.Numeric value will not only be maintained each time you call the step within an instance of the sequence, but now also subsequent sequencial invocations. Next, notice that the report says that you had 10 iterations executed with 0 passed and 0 failed. This means that you got errors on all iterations. Now a looping step reuses the step result as it executes each loop, and the final summary result is a snapshot of the last iteration. Since you are ignoring errors, the numeric value on the step result never gets updated, so the final summary step result is the same as the last UUT. The looping code then sets the loop status to Failed because no iterations passed. Look at the attached report to illustrate the behavior. The report shows you the results from each iteration as well as the parent summary result. In general ignoring errors is a bad idea, but assuming that you want to continue to ignore errors, you can do one of the following in order or ease and best behavior:1) Add a preexpression to set Step.Result.Numeric to a failing value, such as zero or NAN2) Uncheck the "Optimize non-reentrant calls to this sequence" setting, so that a default value of zero will be used for Step.Result.Numeric3) Add another step after the one you are running to see if at least one iteration passed or failed.

NI TestStand

TestStand report shows a passing value as a fail

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Thanks Ray and Scott, your answers are much appreciated!

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NI TestStand

TestStand report shows a passing value as a fail

Re: TestStand report shows a passing value as a fail