Error 9 problem: error messages appearing in TrackPerformance.txt (case 34536)

[raypark70]

To whom this may concern:
I am currently trying to use DT 2016 to display three images in a row, with the second one either being target or foil, and collect RT for each trial. A standard Go-No-Go Task.
My team came up with this solution (see attached file), which seems to run fine, but produces error message and stores in TrackPerformance.txt under DirectRT folder. Here's how it looks like:

Subject 999, 2019-05-13, 오후 3:57:41, Finished. 0 Errors/Warnings.


Subject 999, 2019-05-13, 15:57:55.81 pm, v2018.1.107, Initial Display: 1920x1080, 32-bit colour, 60hz or 16.67ms/screen
Elapsed Time: 424045656ms, block 0, trial 0, stim 2, Error 445, Object doesn't support this action--may be a problem switching to the requested display settings (resolution and/or color depth), on line 440, during Init of Form DDFullScreen
Subject 999, 2019-05-13, 오후 3:57:59, v2018.1.107, Session Display: 1920x1080, 32-bit colour, 60hz or 16.67ms/screen
Elapsed Time: 2840ms, block 1, trial 2, stim 1, Error 9, Subscript out of range, on line 200, during FlipScreen of Form DDFullScreen
Elapsed Time: 3609ms, block 1, trial 3, stim 1, Error 9, Subscript out of range, on line 200, during FlipScreen of Form DDFullScreen
.....(zip).....
Elapsed Time: 7270ms, block 1, trial 8, stim 1, Error 9, Subscript out of range, on line 200, during FlipScreen of Form DDFullScreen
Elapsed Time: 8042ms, block 1, trial 9, stim 1, Error 9, Subscript out of range, on line 200, during FlipScreen of Form DDFullScreen
Subject 999, 2019-05-13, 오후 3:58:11, Finished. 9 Errors/Warnings.


My question would be:
1. Should I be concerned? The RT Log seems fine at this point and no pop-up windows complaining about errors yet.
2. If I should be concerned... is there any way to improve/fix this issue?

Cheers,

"Raymond" Byungho PARK
New DirectRT user (since 2019)

[jason_reed]

A outward bound TTL signal must be followed by another stimulus—it can be any but the last stimulus on a trial. Try adding a blank stimulus (~ in the stim cell displayed for 0 seconds in the corresponding time cell) on the trials in your current .csv file where you are sending a ttl signal. Then try running it again to see if the error messages persist.

[raypark70]

Thank you -- this issue has been resolved now.

[Helenawe]

I don't think you can output TTL using the actual serial port, as that is RS-232, not TTL logic levels. If you're using the serial port, you'll need a converter, like this.