Loss serial input with re install of Labview

[JDesRosier]

Hello,

If the loopback test is working sporadically, your problem exists somewhere within the realms of the hardware. In your previous post, you said that you did successfully complete a loopback test. This tells me that the problem is not with the DAQ card.

My guess, at this point, is that you need to check your serial cable/port connection at the back of the computer to make sure that your cable is securely fastened. Also, there is a good chance that the problem exists within the serial cable. You should replace the serial cable if the connection appears to be secure at the backplane of the computer.

If neither of these solutions work, then the next necessary step will be to escalate the problem t
o the manufacturer of your 3rd party device. It is possible that this device is experiencing internal errors, resulting in no throughput to the DAQ card.

I hope this helps.

Best Regards,

Joe Des Rosier
National Instruments

[sparks48]

I have the loopback working correctly.
I have the LabView Serial.VI read and write working.

I cannot read data into my emveco.vi program.

I am using the serial port (com1) as my input.

I am assuming the emveco.vi is complied and I cannot change the port settings. Is that correct?

I am able to look at the settings in emveco2.vi and have tried to get it to work. I can see the read input but no data is coming in.

It does not apprear that it is using VISA but just serial input. Could that be?

I tried to do the Visa example but Visa was not listed in the options that the program indicated. I thought I had loaded it but it was not listed.

What should I try next?

John

[JDesRosier]

John,

If you open Caliper.vi (the subVI that's called within the enveco.vi shell), you will see the serial port read command. I can see that you're trying to read from port 4, or at least that was the port setting listed on the program you posted in your previous reply.

You say that you're using the serial port (com1) as the input, so you will need to change the port 4 read command to port 1. This should fix your error.

If you decide to use the VISA read commands (I recommend this for simplicity and functionality) rather than the manual serial read polls, then you will want to visit the following link to install the current version of NI-VISA. Once you have this installed, you can follow the instructions in the tutorial to replicate the serial read command using NI-VISA. Within LabVIEW, the VISA template can be easily found by [right-clicking] in the block diagram and following this button sequence [All Functions]>>[Instrument I/O]>>VISA>>VISA.

Please let me know if changing the port number or implementing NI-VISA works.

Good Luck!

Joe Des Rosier
National Instruments

[sparks48]

serial port 1 is port 1 or port 0 in LabView?

[JDesRosier]

If you open Measurement & Automation Explorer (MAX)by going to the desktop, clicking [Start]>>[Programs]>>[National Instruments]>>[Measurement & Automation] and expand [Devices and Interfaces]>>[Ports (Serial and Parallel)], you will see that the standard port alias for LabVIEW is "COM1" without the quotations.

I hope this helps you fix the problem. Please don't hesitate to ask if you need further assistance.

Good luck!

Joe Des Rosier
National Instruments