PXI-6602 with SCB-68 need to aquire 21-bit binary input

[Ray Smega]

I am using a PXI-6602 with a SCB-68 control block.  I need to input the 21-bit binary from a measurement laser, and aquire the data in decimal form.  I have the binary inputs as PFI0-PFI20, the COM is set to ground.  Strobe is into PFI21.  In LabView(7.0), I have added a DAQ assistant, selected Digital I/O then Input Port.  While at the test screen with the row of lights and numerical fields I appear to have no data. I have run out of ideas. Your help is appreciated.

Ray

Message Edited by Support on 07-24-2007 09:17 AM

[Laura F.]

Hello Ray,

I would try inputting a known TTL (5V) signal into a digital line on your device so that you can be sure that it is working correctly.  Instead of doing this in the DAQ Assistant, you could use the test panels in Measurement and Automation Explorer (MAX).  Expand the Devices and Interfaces >> DAQmx Devices category so that you see your device and then right click on it and choose test panels and go to the digital I/O tab.  After you have verified all of the lines are working correctly, you can connect the signal from your laser.  In MAX, you can also check the pinout for your device so that you can verify that all of the digital lines are connected to the correct pins on the SCB-68.  To do this, select your device and right-click to select "device pinouts". 

Let us know how it goes!

Regards,

Laura

[Ray Smega]

I have found a solution now for the problem. I ended up having to add a line into each PFI from +5V through a 10k Resistor. The input is NPN style so then it pulls the signal to ground and gives the correct signal.

Thanks