Serial Communication Issues When Communicating on Same Interface Type

[TishaCrann]

TestStand is receiving the correct Return Count from Serial Read but not receiving the Read Buffer String from LabVIEW.

Current Hardware Configuration:

COM4: RS485 (NI USB-485)

COM5: RS485 (NI USB-485)

COM6: 8432/4 Port1 (RS232)

COM7: 8432/4 Port4 (RS232)

My TestStand Code is pretty simple:

Open Session1

Open Session2

Write Session2

Close Session2

Read Session1

Close Session1

Where Session1=COM4 and Session2=COM5

OR

Where Session1=COM6 and Session2=COM7

TestStand is receiving the Return Count from Serial Read but not receiving the Read Buffer String from LabVIEW. Either with RS232 nor RS485.

I do see the correct message when I open the VI and monitor the Read Buffer String through a probe and the Read Buffer output.

But if I do get both the Return Count and Read Buffer returned string if I do slight changes:

Session1=COM4

Session2=COM6

Realterm Serial Application COM5 (Simulate a Write to Session1)

Realterm Serial Application COM7 (Receives the Written message from Session2)

Session1 Successfully receives the message from Realterm COM5.

I did add delays and user popups.

My LabVIEW Read Serial has an Error Handler for -1073807298 (0xBFFF003E). TestStand doesn't see this error.

[TishaCrann]

Delete this message.

[Foreshadow20]

I used the wrong account to create the thread. Communicate to me through this account.

The NI Logout is different from the forums Log Out...

Thanks.

[Foreshadow20]

Here is the visual of what is happening: COM4 on Session1 and COM5 on Session2. We get the count but not the message.

COM4 on Session1 and COM6 on Session2. Using Realterm to communicate with COM4.

[benthere]

Hi Foreshadow,

I want to make sure I am following your question correctly. When you say the message isn't being written, you are saying the one in the Read Buffer that says "Where is my Message" correct? Could you also post a picture of the message popup settings so we can get a clearer picture of what you are calling?

Thanks,

[Foreshadow20]

I found the issue, but I don't know why it behaves like this.

I was clearing the COMs during the Open of each serial port. I'm not sure why clearing COM5 while initializing it would clear a message that is writen 50ms after the init. The Received Buffer Count was good...

The same execution of the code and delays works without issues if executed in LabVIEW without TestStand.