Noisy DS digital inputs

[jcrawford]

Hello,

We've discovered something interesting with our DS' digital inputs. With nothing attached, they read off. When we connect a 3-pin (PWM signal) wire, they quickly alternate between on and off. When we short the SIG and GND, it reads off. We can't get them to read solid on.

Any ideas?

[Jeremy_B]

Hi,

What happens when you connect the digital input to 5 volts?  The inputs are floating, so if you don't connect them to ground or 5 volts, the value is undefined and will often toggle back and forth between 0 and 1.

Regards,

Jeremy Billheimer
Applications Engineer
National Instruments

[jcrawford]

Ah, that makes loads of sense. We'll try it out next meeting, but I expect that'll work just fine.

Thanks!