Chronos Adapter for BIOPAC MP36 [43887]

This article applies to:

E-Prime 3.0

Chronos

Detail

Experiment Author: Psychology Software Tools, Inc.

The Chronos Adapter for BIOPAC MP36 sample experiment illustrates how to use Task Events to send markers from the E-Prime experiment to the MP36.

Abstract

The sample experiment presents a Visual Oddball Task: each trial presents the letter "O" or "X" and the participant's task is to distinguish between these letters. 80% of the trials present the letter "O" and 20% of the trials present the letter "X". The experiment sends the marker value 1 when the letter "O" is shown and the value 128 when the letter "X" is shown.

The Chronos Adapter for BIOPAC MP36 provides access to 8 digital outputs (from Chronos to the BIOPAC MP36 and eight digital inputs (from the BIOPAC MP36 to Chronos) as shown below:

This sample experiment illustrates the digital output functionality. When Chronos sends a marker on its first digital output, the MP36 receives it on Digital Input #1 (pin 10). When Chronos sends a marker on its eighth digital output, the MP36 receives it on digital input #8 (pin 25). To determine which MP36 digital input receives a trigger value sent from Chronos, do the following:

1. Represent the integer marker being sent as a binary number (see INFO: Choosing a marker value to send from E-Prime to an external device [42529] for more information on integer and binary numbers).
2. Map the binary number to Chronos's digital outputs to determine which outputs are set high (set to 1).
3. Examine which MP36 digital inputs map to the Chronos digital outputs that are set high.

For example, the sample sends the integer value 1 when the stimulus = the letter "O":

1. Integer value 1 equals the binary number 0000 0001 (Least Significant Bit is right-most bit).
2. 0000 0001 sets the first Chronos digital output high; all other digital outputs are low.
3. As shown in the table above, the first Chronos Digital Output maps to MP36 Digital Input 1.

The sample sends the integer value 128 when the stimulus = the letter "X":

1. Integer value 128 equals the binary number 1000 0000.
2. 1000 0000 sets the eighth Chronos digital output high; all other digital outputs are low.
3. The eighth Chronos Digital Output maps to MP36 Digital Input 8.

NOTE: To configure the E-Prime experiment to receive signals sent from the MP36 to one of the Chronos adapter's eight digital inputs, create an InputMask for the Chronos device that looks for the pseudo button responses 1, 2, 3, 4, 5, 6, 7, and/or 8, which map to Chronos digital inputs 1, 2, 3, 4, 5, 6, 7, 8. See Section 6.2 Pseudo Buttons of the Chronos Operator Manual and DEVICE: How To: Synchronize E-Prime with an incoming marker/press via an Input Mask [34380] for details.

NOTE: Extract all the files in the attached .zip file to the same folder. The sample experiment displays images that must be located in the same folder as the experiment.

See Also:

Chronos Adapter for BIOPAC STP100C [42160]