Multiple NI PXI Sharing same CAN Breakout box

[waterox]

Hello,

Quick question: I have 2 PXIe-1078 Chassis with the same exact configuration: NI PXIe-8135 Embedded Controller, 1x NI PXIe-4353, 1x NI PXI-6615, 1x NI PXI 6225, 1x NI PXI 6704, and 1x NI PXI 8352 DeviceNET.

Now, both of the PXI 8352 DeviceNet card (from each PXIe Chassis) are connected to one CAN Breakout box. My question is: "Can I run both DeviceNet Cards at the same time on the same breakout box?" I have not been able to use both. If one card is using the breakout box, the other card cannot use it. 

[ThreeLions]

Hi,

You can use them at the same time as long as the baud rate of the 2 PXI 8532 are the same. If they still cannot run together, please check the CAN cable.

Thanks!

[waterox]

Thank you for the respond. The baud rate is the same for both at 50000. So we have two different host computer running two different VIs. When one runs, the other one gets an error at DeviceNetLIB.lvlib and output a zero state, stating that it is not connected to the desired DeviceNet device

[waterox]

Allow me to give more detail on the error,

"Error -2147136213 occurred at Wait for State.vi

Possible reason(s):

The DeviceNet duplicate MAC ID check fails for the Interface Object. Solution: Determine an unused MAC ID in your DeviceNet System and use that MAC ID for Open DeviceNet Interface"

Currently we only have 3 DeviceNet devices on the network that are connected. One PXI has 1, the other has 2. They all have different MAC ID, so there should be no conflict. But we cannot use both DeviceNet Cards at the same time for some reasons

[ThreeLions]

Hi,

You can refer to the examples, Single Device.vi and Slave IO.vi. You can run the Single Device.vi on a PXI-8532 to perform the communication as a DeviceNet master. Then run the Slave IO.vi on another PXI-8532 to work as a slave. In the Slave IO.vi, please mentioend you should specify the interface MAC ID and the device MAC ID to the same value, so the device works as a DeviceNet slave.

Thanks!

[waterox]

Thank you for the respond. I think I get what you are saying but I have not had success locating 'Single Device.vi' and 'Slave IO.vi' in the NI Example finder and on the internet.

[ThreeLions]

Hi,

You can find example VIs on the following path: Help-> Find Examples...-> Haedware Input and Output-> NI-Industrial Communications-> DeviceNet-> Basic Examples-> PXI&PCI ->DeviceNet PXI PCI Basic.lvproj.

Thanks!

[waterox]

Thank you so much. I'll give it a try now. I'll let you know the result

[waterox]

Hi, 

This might be a dumb question but, how do you integrate establishing slave IO and explicit messaging? I got a working VI using DeviceNet explicit messaging. However, I'm not sure how to add to this program so that it establish my card as slave. My attempt produced: "

Error -1074388986 occured at Open DeviceNet Interface.vi

Possible reason(s):

NI-Industrial Communications for DeviceNet: (Hex 0xBFF62006) the object is already open in another application. Solutions: Ensure that only one application at a time uses an object, and that you close all objects prior to exiting your application (don't use Labview toolbar's Abort button)."

Thank you for your help in advance! 

[ThreeLions]

Hi,

1. Did you use the same DeviceNet interface to the Single Device.vi and Slave IO.vi?

If you used dnet0 in the Single Device.vi, you must choose another DeviceNet interface to using to the Slave IO.vi.

2. Ensure the DeviceNet interface that you chose in the Slave IO.vi didn't be used on other VIs or applications.

Thanks!