I am using labView to collect the data and have it set up with one of the VI's that came with it. The trigger I am using appears to work fine when on a short lead (~1m) but when connected to a long lead (~10m) so as to be operated remotely the logger starts immediately. However it appears that by holding the switch down it is possible to start logging once the trigger is released. What could be causing this? and how do I fix it? I am using a At-MIO-16E-1 board. The trigger is a simple on-off switch and is currently wired to PIAO/Trig1 and the adjacent DGRND pin
10m is a very long unshielded wire. It is likely that it is picking up RF noise. You could look for noise by sampling the trigger with an AI line just to see what it looks like, or you could also add a pull down resistor to the trigger on the end of the wire near the DAQ card.
Thanks. I hooked up the AI line as you suggest and came up with an alternative way of wiring that appears to work, though is perhaps not ideal. I connected the trigger pin directly to ground with the switch connected to the +5V source and the trigger pin. This appears to generate about a 1V trigger signal when the trigger is pressed while remaining at zero the remainder of the time.