Millisecond Forums

No idea offhand. There are a few things syntax-wise that aren't quite ideal, but none of those should elicit a crash; the fact that no crash occurs on a reasonably similar iPad suggests the same. Can you describe in some more detail exactly when / where the crash occurs? I.e. Is it when the fixation cross is displayed? Or when it is tapped? Or when the first sound playback occurs? Does the crash occur at the very start (1st trial) or at some later point? Is it always the same point (e.g. after, say, ~30 trials), or does vary randomly? Or, for example, does the crash occur when some specific item is used?

Thanks.

Hi! thanks. it crashes randomly, but never on the first trial. are there known issues with iOS 11?

No known issues, no. What I'm wondering is whether the crash is really random: That would, for example, suggest that the iPad Air is running out of memory at some point, which is theoretically possible (1st generation Airs weren't super-strong hardware spec-wise, and iOS 11 tends to be a bit more resource-intensive than iOS 9; or the iPad in question might have some bad RAM). Alternatively, the crash might just appear to be random, but actually there is something systematic going on: A specific audio or image file used in a specific trial might cause a problem, but because the specific trial is run at different times in the various conditions in your script, this ends up looking random.

If you run only the 1st condition in the script a couple of times, i.e.

<expt orderA_1>
/ groupassignment = groupnumber
/ subjects = (1 of 8)
/ blocks = [1=test1]
</expt>

executing <block test1>, when -- approximately -- does the crash occur during each respective run?

Hi Dave, thanks so much for replying so quickly!

I think you're right because I tried it on an iPad with a bigger processor w iOS 11 and it works perfectly. So it's an interaction of small processor/RAM with the new iOS I think. So I'll just run it on the better iPad for the short-term and look into fixing any code/file size inefficiencies or downgrading the other iPad in the long term if I need to- so I should be back at some point with an report on when it crashes (it's just that I have 16 conditions now so that would probably take a while to go through).