Crio 9871 doesnt ouput

[JPLEng]

I have a 9871 module that doesn't seem to output when I perform a serial write. Confirmed both with an O'Scope and by the Serial Read command which times out.

MAX shows the 9871 as being in the systems.

Project shows it as well. But when I run my Labview code it shows it as executing properly.

Am I missing something or do I have an effective module.

I do haveScan Engine support installed on the system. And I have  instaled the NI 987x serial support on the RIO.

Any suggestions??

Thanks in advance

[sparkysquared]

Hey JPLEng,

It sounds like you've already set up this device with the proper serial support, but please look through the following documentation to make sure you have the necessary software on your cRIO (just to double check):

Configuring the NI 987x Modules in Scan Mode

http://digital.ni.com/public.nsf/allkb/16989C708E5AF2C1862578A90067D9DC

If the device is properly configured, then the next step is to determine if this issue is with your LabVIEW code. To do this, we can test the serial ports directly using VISA Test Panels in MAX and a loopback test as explained in this document:

How to Do a Serial Loopback Test

http://www.ni.com/white-paper/3450/en

Hope this helps!

--Ryan S.

[JPLEng]

Hey Ryan:

Thanks for reply.

I indeed saw those papers you mentioned and implemented what they instructed, including downloading a Serial Loop self test vi.

Still no go..

Is it possible the order in which software is loaded has an effect?

For another data point I tried running the serial loop test on the controller port 1 serial port and it worked fine. Its just with the modules I'm not having any

luck.

I have not tried getting the modules to output(write) something using MAX. It did not seem that intuitive. Is that perhaps a worthy road to go down and

try to get working?

Any more tips.

Thanks

Alex

[Wayne.C · Accepted solution]

JPLEng,

Did you double check the power connection to the 9871 module?

[Alisha_P]

I think I'll echo Wayne: Do you have the external power supply between 8 and 28 V hooked up to the 9871 as shown in Figure 2 of the 9871 manual?

[JPLEng]

You know for such an obvious suggestion I was about to quickly reply with "OF COURSE I DID" . After all the green light is lit on the controller.

But then I paused and took a closer look and saw the power connector on the  module and  felt like a ........Well you know.

So turns out, youre right. That was it. It's working now.

Thanks for the tip.

I've learned and forgotton that often it is the obvious.

Thanks again.

[Wayne.C]

JPLEng,

Trust me, you're not the first and definitely won't be the last to miss that.  How do you think I knew to ask the question based on the symptoms?