07-28-2021 10:13 AM
I'm trying to get a 9870 RS232 module working with 9147 cRIO chassis with Scan mode with some strange results. I see the serial ports in MAX but not the IO ports, but I see the IO ports in my project tree but not the serial ports. I can't seem to find anymore software to shove into either the laptop or chassis so I'm out of clues.
07-28-2021 01:09 PM
The serial ports are VISA resources accessed through the NI-VISA functions. They do not show in the project tree since they are not accessed through that. The IO points are Scan Engine shared variables. NI Max does not show them since it is not dealing with shared variables. The project does, since shared variables are an integrated component of a LabVIEW project.
To access your serial port in a LabVIEW program you use the VISA functions. The VISA Configure Serial Port function is likely the first you will want to look at. ViSA Write and Read the next two.
07-28-2021 02:22 PM
Averna, Thanks for your reply. I had tried VISA configure earlier and all I see is the COM 3 port on the laptop. I still see the ports in MAX though. There's a disconnect somewhere.
07-28-2021 02:42 PM
VISA Configure Serial Port needs to be called from a VI that is placed under the device entry for your cRIO device. If you just open it from disk it will open in the MyComputer context, which is your local host computer and it will only recognize the serial ports from your host computer.
07-28-2021 03:41 PM
Hi Rolf, Yes I've seen VIs under the device in sample projects. All I get is a gray'ed out "FPGA target (LabVIEW FPGA not installed on host)". I also see it is installed in my software tree under LabVIEW 2020. so this ends a day with no progress whatsoever. thanks for all your help!
07-29-2021 04:12 AM
Hi Andy,
I am speculating - never worked with an expansion chassis - but it might be that it is not possible to use NI-9870 in an expansion chassis with-out a compactRIO with an controller.
The important point about the cRIO-9147: it it not a stand-alone cRIO but an expansion chassis which you usually use in connection with a full-featured cRIO with an controller (like a cRIO-905x or cRIO-904x). That is where LabVIEW code under the real-time OS will run.
You cannot deploy or develop any real-time executable for this expansion chassis.
So currently you have no real-time target from where you could "locally" acces the VISA resource of the 9870.
One random shot/suggestion:
Did you install the VISA-server on the cRIO-9147 (if that is possible at all). That might make the 9870-VISA resource available over TCP/IP.
Regards, Jens
07-29-2021 07:49 AM
Hi Jens, I have VISA installed and NI-Serial 9870 and 9871 Scan Engine Support installed among other things in the chassis. I'm trying to follow the document "Discover, Configure, and Communicate with NI 987x Modules in Scan Mode". I fail to see the ports in my project tree after I "deploy all". That's where I'm stuck at.