[solved] I would like a pause button

Johan_P

Hello everyone !
I'm beginner with opensesame.
I'm currently running and experiment using EEG. I would like to setup a button or something, which would allow me to make a pause at any moment.

Sometimes, an electrodes detach itself and I would like to be able to pause my OpenSesame script to repair the electrode.

Any idea ?

I searched in the documentation but I didn't find anything about a pause.

Johan.

sebastiaan

Hi Johan,

OpenSesame doesn't have a pause button, but you could implement one quite easily. The most convenient way to do this depends on your experiment, but the following is one option.

1. Disable 'Flush pending key presses (...)' in your trial_sequence.
2. Add a new keyboard_response to the start of your trial_sequence. Disable 'Flush pending keypresses', set the timeout to 0, and set the allowed responses to p.
3. Add a new sketchpad just after the keyboard_response. Add a text message like, 'The experiment is paused'. Set the run if statement for this sketchpad to [response] = p.

Do you see the logic here? Basically, if you press 'p' somewhere just before a new trial starts, this will cause the pause sketchpad to be shown.

Hopefully this will get you started!

Cheers,
Sebastiaan

Johan_P

Okay Sebastiaan,
I think I see how it could work. I will test it when I have some time and come back here to make a feedback.

Cheers,
Johan

Johan_P

Hello,
So I tried a lot of thing running with this idea but i must be doing something wrong. i never had the good result.

Most of the time, either I obtain a black screen (at the beginning of my sequence, when I put the two element here) and the experiment continues only if I press p, or I have a problem with the variable name. [response] does not exist in the sketchpad element...

I tried with the two item at the beginning at the sequence, at the end, nothing changes.Perhaps you will have other idea or correction.

or

sebastiaan

Hi Johan,

I cannot really tell from your example what goes wrong, but the instructions in my previous post should work. Except for this, which I hadn't considered:

I have a problem with the variable name. [response] does not exist in the sketchpad element...

I forgot that the variable response does not exist at the beginning of the experiment, so the run-if statement [response] = p will cause an error. To fix this, you can simply add the following line to the top of your experiment's general script:

set response None

This will give response an initial value.

To get you started, here's a working example of a pause button:

• http://pastebin.com/jY5fDCpF

Good luck!

Sebastiaan

Johan_P

Yeah,
I just tried your advice and it's working. The problem was due to the value of the [response] variable.

Thanks !

Johan_P

Okay it worked 3 times and now it fails every time.
I will work on it and come back if nothing work.

Bye,
Johan

Johan_P

Hello,
I really think the idea is good but it fail to work with my script.

Johan