User manual

106 Data Files

4.9.3.3

4.9.3.4 Buttons

4.9.3 Event Line Formats

Each type of event has its own line format. These use some of the data items

listed below. Each line begins with a keyword (always in uppercase) and items

are separated by one or more tabs or spaces.

DATA NOTATIONS

<eye> which eye caused event ("L" or "R")

<time> timestamp in milliseconds

<stime> timestamp of first sample in milliseconds

<etime> timestamp of last sample in milliseconds

<dur> duration in milliseconds

<axp>, <ayp> average X and Y position

<sxp>, <syp> start X and Y position data

<exp>, <eyp> end X and Y position data

<aps> average pupil size (area or diameter)

<av>, <pv> average, peak velocity (degrees/sec)

<ampl> saccadic amplitude (degrees)

<xr>, <yr> X and Y resolution (position units/degree)

Messages

• MSG <time> <message>

A message line contains the text of a time stamped message. This will have been

sent to the EyeLink 1000 tracker by an application, and contains data for

analysis or timestamps important events such as display changes or subject

responses. The <message> text fills the entire line after the timestamp and any

blank space following it.

• BUTTON <time > <button #> <state>

Button lines report a change in state of tracker buttons 1 through 8. The

<button #> reports which button has changed state. The <state> value will be 1

if the button has been pressed, 0 if it has been released. Tracker buttons may

be created to monitor any digital input port bit, and may be created by link

commands or in the tracker configuration file BUTTONS.INI.