Trigger saving glitch

Post Reply
noxid
Posts: 2
Joined: Thu Jul 15, 2010 12:43 pm
Location: Switzerland

Trigger saving glitch

Post by noxid »

Hello,

I've recorded some data with triggers (10ms) that were sent by an other computer (via the USB box) and they only appear in your BDFreader and no other software.

I used a third computer to retest the recording and this time the triggers were visible in my other readers. Can lag of a computer mess up the writing of the triggers (my computers are heating up a lot due to their location in a closed backpack)? Is it possible to manually resave the data from your BDFreader?

Thanks

Alex

Coen
Site Admin
Posts: 1124
Joined: Fri Mar 26, 2004 7:00 pm
Location: Amsterdam, Netherlands
Contact:

Post by Coen »

If the BDFreader shows triggers, then there are triggers saved in the BDF file. If other readers do not show theses trigger (sometimes), then there is a problem with these other readers.

Best regards, Coen

noxid
Posts: 2
Joined: Thu Jul 15, 2010 12:43 pm
Location: Switzerland

Post by noxid »

Hello again,

I've done some further testing and it would seem that if I launch my trigger sequence before I start actiview and then launch the recording my triggers in any reader are fine. If I start recording before my trigger sequence it defaults to 8 bit triggers in all alternate software readers and misses the higher ones. I am using triggers 1-4 and 9-10 in this experiment. 9-10 are ignored in the later scenario.

Coen
Site Admin
Posts: 1124
Joined: Fri Mar 26, 2004 7:00 pm
Location: Amsterdam, Netherlands
Contact:

Post by Coen »

Use positive trigger logic (High = trigger, Low = idle), return all trigger lines to Low after a trigger, and keep unused trigger lines Low (either by your trigger software, or by a hard wire connection to ground, pin 37), length of trigger pulse should be longer than 1 sample period.

Best regards, Coen (BioSemi)

Post Reply