Connecting the RT to the computer by crossover cable

[Ahedayat]

I have a problem in connecting the real time to the host computer by crossover cable. Sometimes it gives me the error that the connection with the RT is lost. Whenever I get this error, I can't connect the RT to the computer anymore.  Although the Ip is set to be the same, the led light on the ethernet port of the RT doesn't blink. I think there is a problem in connecting my RT to the computer. I appreciate if you can help me to figure this out.

Thanks,

Ahmad

[Peñata]

Hi Ahedayat,

Are you following the directions in this KB?

Aaron P

National Instruments

Applications Engineer

http://www.ni.com/support

[Ahedayat]

Thanks Aaron, 

Yes, I followed the instruction completely. It seems there is a hardware defect in our PXI. Whenever the real time disconnects from the PC, the ethernet light turns off and there is no communication between the RT and the PC. The RT is connected to the PC by crossover cable and  the link lights should be displayed when a valid connection is present. Shouldn't?

After having this problem, I can not make the Rt and PC talk but if I plug the RT to other ethernet cards on other computer, the light starts blinking and after that I unplug from the other computer and connect the cable to the PC and it works. Is it a sign of hardware defect?

What should I do to solve this issue?

Thanks,

Ahmad 

[Tanya_V]

Hi Ahmad,

What steps to you take to reproduce this error? Does it always happen after performing a certain action or is it random?

Have you tried using another crossover cable?

Could you also include your driver version and the model number of the PXI controller in your next post?

Thanks!

[Ahedayat]

Thanks Tanya, 

 As far as I can tell, it is random. I have been using a crossover cable between the RT and the PC and the performance was very poor. I was getting this error almost every time I run the code and directly after the error, the led light turned off and I had some issues in reconnecting the RT. 

I switched to regular Cat5 cable and the performance improved. I was still receiving this error but the physical connection was ok and the light was still one on the ethernet card of the RT except for one time that the RT has been totally disconnected from the PC. After that, I have tried different cables, regular and crossover, and Hub switch, every thing failed. I plugged the RT to another computer and suddenly RT ethernet card started blinking and I just unplugged the cable abd plugged this again to my computer and it continuous working. 

I am using Labview version 2009 on both the computer and RT. I an using PXI-1042 with NI PXI-8106 real time controller.  

Thanks,

Ahmad 

[Tanya_V]

Hi Ahmad,

Does the error only occurs when you run your code from the LabVIEW development environment? If so, does your code run for some amount of time and then error out?

The problem may be that your code is starving the network thread. You may want to try increasing the wait in your highest priority loop to see if that helps.

Let me know what happens when you try that.

Take care!

[Ahedayat]

Hello Tanya, 

Thank you very much for your great help. I have tried to format the RT but I 
wasn't able to do that. At first, I pulled out the controller and changed the 
dip switch according to the PXI manual (Pic attached). As a side note, the 
switch number one was on! when I pulled this out. 

Then, I opened MAX and clicked on the device under remote system and selected 
format disk. It gives me the error which is attached.


Thanks, 
Ahmad

[Tanya_V]

The BIOS may not be set to look at the hardware switch to choose whether or not to boot into safe mode. For a PXI system, the boot configuration can be found by booting into the BIOS and looking for Advanced»LabVIEW RT Options»Boot Configuration. Here you can choose to either boot into safe mode, boot into RT normally or look at the hardware switch.

Hope this helps!