Biopac Timestamp Synchronization

This step by step wiki explains how keep the BioPac timestamps synced up with the foraging software generated timestamps. Part I covers how to synchronize the system clocks for both the biopac machine and the foraging client machine. Part II covers the AcqKnowledge - BioPac sync instructions. Before running an experiment yo should check that biopac machine and foraging client machine clocks are synced and that you are following the AcqKnowledge - Biopac sync instructions up to the point where you should be recording (step 6).

For Part I we used two machines running Windows 7. For part II we used AcqKnowledge 4.1.3 for Windows, along with a biopac MP150 connected to a TEL 100C module, a TEL 100M-C 4-CH Transmitter and a SS3A EDA.

Part I

Step 1:

One of your machines will be running the game server and the biopac software while the other will be running the game client. On the server start Windows Command Line utility and type 'ipconfig' to find the server ipv4 address.

Step 2:

On the client start Windows Command Line Utility as administrator by right clicking on 'cmd' and selecting 'Run as administrator' (admin privileges needed obviously).

Step 3:

On the client command prompt enter the following command:

NET TIME \\{server ip address} /YES

You'll be prompted to confirm you want to sync the client clock with the server clock.

Part II

Step 1:

Setup the biopac hardware and open AcqKnowledge.

Step 2:

Go to "Setup Segment Labels" from the dropdown menu "M150" from the menu bar.

Step 3:

Add a new segment label with label "timestamp" and be sure to check the time checkbox. No need to include date. If there were no preexisting segment labels, the recently created segment label should have index "1".

Step 4:

Go to "Setup Channels" from the dropdown menu "M150" from the menu bar.

Step 5:

Setup your channel (in this example we used a 1000 sample per second sampling rate). In the "Label" field input the segment label index you added in step 3. Under normal conditions, this should be "1".

Step 6:

Start a new EDA recording. In this example we recorded the incoming signal for approximately 4 seconds.

Step 7:

Go to the beggining of your recording. In the event bar (white horizontal space right above the EDA recording graph) you should see a small red marker for the start event. Right click on the marker and select "Edit event".

Step 8:

Select "Summarize in Journal" from the option panel.

Step 9:

You will be prompted to create a new journal. Click yes

Step 10:

Be sure to summarize all types of events.

Step 11:

A journal with the recording start timestamp will be displayed on the journal log on the bottom of your screen. Keep the journal log open.

Step 12:

Go to "Horizontal Axis" from the dropdown menu from "Display" on the menu bar.

Step 13:

On the "Horizontal Scaling" panel, select Time(HH:MM:SS) as format and input the timestamp displayed on the journal as first sample. The sample interval should match your channel sampling rate.

Step 14:

Notice the horizontal axis scale on the recording graph now displays day time.

Step 15:

All set! To get a txt with the timestamps + EDA recordings save the file as a txt. On the "Write text file options" panel check the "Horizontal scale values" checkbox. In precision, input how many siginificant digits should be included in the text file fields.

Step 16:

Your text file should look very similar to the example. The example text file contains 4,124 observations (timestamp + EDA) for our 1000 sample per second, ~4 second recording.

You can find the example text file on the following link:

wiki_example.txt