Jump to content
flintstone

Measuring the PXIe bus

Recommended Posts

Hi,

I am searching for a nice solution to measure the PXIe bus signals (the single-ended signals like the real-time trigger bus, no need/equipment for measuring the data transfer). The reason is that we want to verify one of the modules built by a contractor behaves correctly with regard to these signals. The easy solution I was thinking of was to have an extension card that I can insert into the rack and it routes the signals to a multi-pin connector where I can attach an oscilloscope and also connect a signal pin with a supply pin using a pull-up resistor. But I do not find this type of card, maybe because the search keywords I use are bad.

Do you know of a supplier that produces such cards? Or do you typically use other ways if you want to measure the PXIe bus directly.

Cheers,

flintstone

Share this post


Link to post
Share on other sites

I'm not sure that would work - it looks like it's cPCI. Do they have a PXIe version?

Oops, good catch - I overlooked the express part. I don't see a PXIe version, but I've been successful in the past getting custom hardware quotes from Pickering. However, it doesn't look like Pickering does *any* PXIe equipment, so you'll probably have to check out some other vendors. You may end up having to fork over some cash for NRE.

Share this post


Link to post
Share on other sites
However, it doesn't look like Pickering does *any* PXIe equipment, so you'll probably have to check out some other vendors.

You're right - it doesn't look like they even have a PXI riser either.

You may end up having to fork over some cash for NRE.

...and then sell it to people like me! :)

These look kind-of interesting...

Share this post


Link to post
Share on other sites

I have the advantage of working for NI so I have ready access to PXI FPGA boards which can read the lines and return what they see. If you have any this is quite straight forward can can give 5ns resolution.

The risers look good but remember that the trigger lines are one the additional connectors, not cPCI/e connectors.

(null)

Share this post


Link to post
Share on other sites

D'oh, I forgot to write back on this topic, sorry!

We will solve the problem now by using backplane connectors for PXI and measure directly on the connector, maybe we modify it a bit for that. Should work for what we plan and be pretty cheap.

@James: I also thought about using one of our FPGA cards for that but I assume that there is bus driver circuitry between the FPGA and the backplane. Our test aims to verify that our contractor managed to leave the backplane lines on High-Z if configured for it (with different configuration it will drive the real-time trigger bus), so this is not clearly in the digital domain. I would therefore not trust the result I get from the FPGA back in this situation.

For many other types of measurements I would just do as you proposed.

Cheers,

flintstone

Share this post


Link to post
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.


×
×
  • Create New...

Important Information

By using this site, you agree to our Terms of Use.