Hybrid communication over USB

[MimiKLM]

Hi,

I'm thinking about the concept how to conncet the devices with the computer to do the test. If you guys coud comment and give any hint that would be great.

The main problem is: How to talk to one device from two controllers?

I have to communicate with the DEV3 from the MAIN HOST and DEV0. However, the devices are conncted amongst them thru different media (GPIB and USB).

It wouldn't be a problem if my connection look like below:

In this case the topology B (B1 B2 B3 and BC) would have two controllers which is completly fine.

However, my topology is hybrid and looks like below. For reminding, I need to communicate with DEV3 from DEV0 and the main host.

My questions:

1. Is it ok to connect USB port on MAIN HOST with the USB port on DEV0 (with the connection BC2) and doing so connect to the topology B with the second controller? It would work with GPIB connections only as I've shown on the first picture. 

2. Do you have maybe any other concept how to do this?

BTW: Please forget about the BC1 connection shown on figure 2. It is bit misleading to have this connection BC1 drawn on the picture 2. Phisically it won't be present. 

Many thanks,

K.

[Clad19]

Hi MimiKLM,

Thank you for posting this issue on the forums. 

I wanted to ask you some further questions regarding your system set up. 

What are the devices you are trying to control? What are the controllers? I understand that the MAIN HOST is a laptop/desktop and that DEV0 is a separate controller. Is this correct?

Have you managed to try connecting your system as in the second image? By this I mean with the USB connection as well as the GPIB connection.

Does Dev 3 have >1 USB port? An alternative could be to communicate directly from the MAIN HOST via USB to Dev 3 if this was possible. 

Just to be clear, in image 2, you mentioned to ignore BC1. Does this mean that in your hybrid configuration you will be using just USB from the MAIN HOST to Dev 0?

Here are some links that may be useful to you:

- Using Two GPIB-232CT-A Controllers as GPIB Extenders

- How Do I Communicate Between Two GPIB Devices on One Computer?

Would you be able to explain what type of application you have developed using LabVIEW and Teststand as well?

I look forward to your reply.

Kind Regards,