DAQ malfunction

[B4S3M]

I am using a usb 6008 DAQ in some expirements i am doing, i tried to connect the DAQ and i discovered that all the digital ports are connected to together (short circuited), also all the pins are high (triggered) on testing using NI tool (Measurement and auotmation). is this normal case? or is it a malfunction?

[RobCole]

Are the pins for those ports connected to anything? If not, then, yes, the inputs could easily "float high". This is not an unusual situation.

     Rob

[B4S3M]

what about being short circuited ? 

[RobCole]

Do you mean that you apply a signal to one input pin and all of them change?

Is your DAQ task set up for line input or port input?

Try tying the unused pins to ground and then check again. Does your input stay low? Or does it change state?

In MAX (Measurement and Automation Explorer), click on your device in teh Devices and Interfaces list and then click on the button marked properties. Check the tab marked Power-up States. You should be able to select what state you want the device in when powered up.

Rob

[SnowMule]

They're all pulled high through an internal pull-up resistor.

Wire an input to ground then read the port/line, it'll make the transition to low.

But with nothing connected, yes, they should all read 5V relative to ground because of that internal pull-up.