Adding EEG Markers to an E-Prime Script
Adding markers to an E-Prime script allows Neuroscan to record the times when events occur during the experiment. Without this information, no analysis based on events can be done. Neuroscan will accept an integer marker (1 - 255). Neuroscan requires that a reset marker be sent from e-prime between each event marker. We usually send a reset event at least 50 ms after each event marker. The reset marker is the number 0.
- Click Edit > Experiment
- Click Device Tab
- DoubleClick Port device (If no port device exists, click add and select port)
- Set Port properties :
- Collection Mode = Presses Only
- Address = 889
- Size = 8
- Invert = Yes
- Mask = &h78
- Emulate Device = None
- Set Lpt constant
- In the user script set a global constant:
- Const LptPort1% = &H378
- Enter Markers in code
- A marker can now be sent in any inline code with the following syntax:
- Writeport LptPort1%, X
- where X is an integer or integer variable
- Note: You must reset the marker at least 50ms after each marker is sent by sending the number 0 (Writeport LptPort1%, 0)