362013-04-04 15:33:37MaartenVanCasteren352013-03-08 10:02:45localhostconverted to 1.6 markup342012-11-19 11:24:08MaartenVanCasteren332012-11-12 17:13:46MaartenVanCasteren322012-10-23 15:58:47MaartenVanCasteren312012-10-23 15:57:26MaartenVanCasteren302012-10-23 14:03:44MaartenVanCasteren292012-10-22 14:08:10MaartenVanCasteren282012-10-22 14:06:31MaartenVanCasteren272012-10-22 13:56:44MaartenVanCasteren262012-10-18 13:52:41MaartenVanCasteren252012-02-23 13:14:29MaartenVanCasteren242012-02-23 13:13:51MaartenVanCasteren232012-02-23 13:13:30MaartenVanCasteren222010-07-01 12:38:18test113.mrc-cbu.cam.ac.uk212010-07-01 12:36:15test113.mrc-cbu.cam.ac.uk202010-07-01 12:35:56test113.mrc-cbu.cam.ac.uk192010-07-01 12:28:56test113.mrc-cbu.cam.ac.uk182009-10-15 15:55:39MaartenVanCasteren172009-10-12 11:55:36MaartenVanCasteren162009-10-12 11:54:35MaartenVanCasteren152009-10-12 11:54:06MaartenVanCasteren142009-10-12 11:51:31MaartenVanCasteren132009-10-12 11:43:53MaartenVanCasteren122009-10-08 16:08:15MaartenVanCasteren112009-10-01 16:10:13ElisabethvondemHagen102009-06-30 10:22:02MaartenVanCasteren92009-06-30 10:21:04MaartenVanCasteren82009-06-30 10:14:48MaartenVanCasteren72009-06-30 10:13:52MaartenVanCasteren62009-06-30 10:12:00MaartenVanCasteren52009-06-30 10:10:31MaartenVanCasteren42009-06-30 10:08:34MaartenVanCasteren32009-06-30 10:07:27MaartenVanCasteren22009-06-30 10:03:28MaartenVanCasteren12009-06-30 09:32:43MaartenVanCasteren

When using E-Prime with a SMI eye tracker, E-Prime should communicate with iView X, the eye tracking software, to start and stop the recording, indicate the start of each trial, specify the stimulus used and finally save the data. The way SMI prefer to do this is by using an ethernet connection and the UDP protocol, but E-Prime cannot handle this. For this reason SMI have developed a toolkit that can take care of the communication with the eye tracker. The toolkit consists of two parts: first a dll file that contains the actual executable code, and second an E-Prime package file that makes sure the functionality in the dll is available within an E-Prime script in a user friendly way. Here at the CBU we have upgraded the package file somewhat, so we are not using the original SMI package file. To be able to use an eye tracker with this toolkit you need to do the following: 1 - Add the package to your E-Prime script. In the 'structure' window double-click on 'Experiment' and then select the 'Packages' tab. Press 'Add' and select the 'iView_X_SDK_CBU' package. If this is not available you'll have to install it: the file 'iViewXAPI_CBU.epk2' should be in 'Program Files\PST\E-Prime 2.0\Program\Packages'. If the Packages folder doesn't exist, it should be created. 2 - At the start of your experiment, add these lines, in an inline object: 3 - You need to calibrate the eye tracker before you can use it. Put this code in an inline object to do so. 4 - You then should check the calibration to see if it was sufficiently precise. This is called validation. You should repeat calibration and validation until you have the required precision. 5 - Just before you start presenting your stimuli you should start the eye tracking recording 6 - At the start of each trial, or just before your main stimulus is being presented, add a 'message line', preferably with your stimulus name as an argument (NB if you are presenting images, sending the name of the image file you are presenting will greatly facilitate analysis using the BeGaze software, as the associations between the trial and image will then be made automatically by the software. For more info, see BeGaze): 7 - Finally, at the end of th experiment put these lines in an inline object: Obviously, the filename can be changed to whatever is best for you. Note that iView X cannot save to a directory that doesn't exist, so make sure to either create the correct directory, or write to root.

When running the script you should go through these steps: 1 - Switch on the eye tracking hardware and install your subject. 2 - Start the iView X program on the eye tracking computer. 3 - Make sure the eye picture looks good and the eye gaze is correctly tracked. Verify this by asking the subject to look at all 4 corners of the screen. 4 - Run your E-Prime script. The calibration uses the settings specified in iView X, which means that you will have to specify 'auto accept' or other settings there. The only thing that the script sets is the number of calibration points used. This is set to 13, but can easily be changed to another value. One warning: this code hasn't been tested much yet, so might not always work as expected. Be careful and please report any problems to Maarten van Casteren.

And you can do drift correction using this script. This is still in the old form, using the serial port. This is NOT compatible with the other code above, but SMI have promised that drift correction will be part of the new version of the SDK, so we will be able to use it soon, hopefully. 500 then MsgBox("Communication failure, time-out after 500 attempts") Stop end if ]]> 0 then ]]>The main advantage of letting E-Prime take care of the calibration is that you don't have to use WinCal any more. Combine these E-Prime scripts to start the recording, do the calibration, validation, drift correction, mark the trials, stop the recording and save the results to disk.