External Trigger via LabJack

[ursi]

Hi,
I wanna trigger a Vizard-function via an external trigger (via LabJack). How do I do that?

I wrote the following code using 'vizact.waitsignal':

##############################
import viz
viz.go()

import u12
d = u12.U12()
##############################
Trigg = d.eAnalogIn(0)

#Create the signal object
sig = vizact.signal(Trigg > 0)

#Create an action to wait on the signal
waitsig = vizact.waitsignal(sig)

def ExtTrigg(waitsig)
### add SOUND
song = viz.add('Beethoven.wma')
song.loop(viz.OFF)

#viz.callback(viz.Event,ExtTrigg) ##?
viz.callback(viz.ACTION_BEGIN_EVENT,ExtTrigg) ##?
##############################

Thanks!