BioSemi.nl

We are using the latest version of Actiview with Presentation software to run the experimental protocol and send stimulus/response codes to Actiview.

Actiview does not receive the least significant bit of the event codes from Presentation. (i.e. all odd numbered event codes).

Any ideas?

Test the trigger input of the USB receiver by connecting Pin 1 (trigger 1) with Pin 37 (ground). Trig 1 should go Low when the connection is made. Without this connection, Trig 1 is High because of the internal pull-up. Use the "analog" trigger display mode.

Best regards, Coen (BioSemi)

We tested the trigger input of the USB receiver as directed. This worked.

Any ideas as to what is wrong with Presentation?

May be obvious, but have you checked continuity of the cable ?

Best regards, Coen

I have checked the cable with a multimeter and its integrity has been verified.

The Biosemi FAQ lists the following pin assignments:

Presentation Parallel : Gnd(25) 1 2 3 4 5 6 7 8
Biosemi : Gnd(37) 2 3 4 5 6 7 8 9

These are the pin assignments that the cable makes (as checked by multimeter).

However, Connecting Pin 1 to Pin 37 on the USB interface causes trigger one to activate on Biosemi. Shouldn't this occur when Pin 2 is connected to Pin 37?

The table in the FAQ on our website means to say:

Pin 1 Pres: Not Connected
Pin 2 Pres - Pin 1 Bio
Pin 3 Pres - Pin 2 Bio
...
Pin 8 Pres - Pin 7 Bio
Pin 9 Pres - Pin 8 Bio
Pin 25 Pres - Pin 37 Bio

Best regards, Coen (BioSemi)

Dear Guys,

I believe, as New Zealand is anti-poden the codes for triggering are wrong as well (-;)

No seriously, here is the solution:

In Port Settings of Presentation make sure to have the following set 9in the latest version of Presentation) you see the following:

Output Ports:
Port LPT 3 (for example)
Data Source: Data port
Register Span: 1
Inversion Mask: 0 >>>>>>>>>>>>>>>> if this is set to: 1 then a code 1 > 1; 2>3; 3>3; 4>5 and so forth ---- if its set to default: 0 then the codes are 1>1; 2>2;3>3;4>4 and so forth!!
Default Pulse width: 5

However, again for your re-collection, the trigger cable must be wired as below:


DB25 Pin 1 >>>> not connected
DB25 Pin 2 >>>> Pin 1 DB37
DB25 Pin 3 >>>> Pin 2 DB37
...

DB 25 Pin 9 >>>> Pin 8 DB37

DB25 Pin 25 >>>> Pin 37 DB37

Again, the first 8 bits on the DB37 (1-8) are connected to the DB25 connector (pins 2-9) and GND is 37, resp. 25 on the DB25. All other pins on the DB37 must be shorted to 37. Having this setup would give you all you need from the hardware perspective.

All the best, Marc Mosimann

Small correction to the entry of before about shorting pins in the DB-37 connector:

In the DB37 pins 9 - 16 may be shorted, depending on what is connected, however do not short pins 17-31 (trigger outputs), pin 32 (sample rate clock output) and pin 36 (5V supply) to ground (37)!.

Hoping this makes more sense now, otherwise an entire layout of the trigger port is available on the BioSemi website.

Cheers, Marc