Attempt to drive PXIe 6739 with labscript suite

35 views
Skip to first unread message

Padia Parth Kiranbhai

unread,
Nov 15, 2021, 12:42:50 PM11/15/21
to the labscript suite
Hi all,

I am new to labscript suite, so pardon me if I am mistaken.
To begin with labscript suite, we got RPi Pico and have flashed the drive with Prawnblaster configuration for pseduoclock implementation. Our goal is to control Ni PXIe-6739, however when defining acquisition rate on device initialization it gives an error that they can't be set because it has no analog inputs (which is indeed true). PXIe-6739 doesn't have any AI channels. How do I go about using labscript suite with PXIe 6739?

Best,
Parth

Chris Billington

unread,
Nov 15, 2021, 3:07:14 PM11/15/21
to labscri...@googlegroups.com
Hi Padia,

Analog acquisition is currently the only kind of acquisition labscript supports for NI DAQmx devices, so setting the acquisition rate only makes sense for devices that have analog inputs.

Simply omit the acquisition_rate argument from the initialisation, and you won't get the error.

If you are looking to do digital acquisition, unfortunately that's not supported at the moment. Implementing it would not be too difficult given it is very similar to analog input, but it seems few have had the need for it so far so nobody has put in the work yk add the functionality yet.

Hope that helps,

Chris


The information contained in this electronic communication is intended solely for the individual(s) or entity to which it is addressed. It may contain proprietary, confidential and/or legally privileged information. Any review, retransmission, dissemination, printing, copying or other use of, or taking any action in reliance on the contents of this information by person(s) or entities other than the intended recipient is strictly prohibited and may be unlawful. If you have received this communication in error, please notify us by responding to this email or telephone and immediately and permanently delete all copies of this message and any attachments from your system(s). The contents of this message do not necessarily represent the views or policies of BITS Pilani.

--
You received this message because you are subscribed to the Google Groups "the labscript suite" group.
To unsubscribe from this group and stop receiving emails from it, send an email to labscriptsuit...@googlegroups.com.
To view this discussion on the web, visit https://groups.google.com/d/msgid/labscriptsuite/e25a0933-63ed-4415-aeed-acaff13a5d81n%40googlegroups.com.

Padia Parth Kiranbhai

unread,
Nov 15, 2021, 4:28:14 PM11/15/21
to the labscript suite
Hi Chris,

Thank you for the quick response. I omitted the acquisition parameter, but now I believe PyDAQmx doesn't recognize my clock. For PXIe 6739, there are 20 Digital I/O channels - 4 of them are buffered and rest of the 16 are static. I am connecting my clock to one of the static I/O but I get the attached error (along with the connection table script). Please guide me how to resolve this issue. Many thanks!

Best,
Parth
ni daq config.PNG
Nidaq error.PNG
connection_table.py

Chris Billington

unread,
Nov 16, 2021, 5:18:34 AM11/16/21
to labscri...@googlegroups.com
Hi Padia,

These non-buffered digital IO terminals have multiple names: they can be named either by their port and line number, or as a PFI terminal. But for specifying which terminal the clock is connected to, the NI DAQmx library requires the PFI name, and the port-and-line name doesn't work.

I see in the device pinout that port1/line0 corresponds to PFI0. Try replacing 'PXI1Slot2/port1/line0' with 'PXI1Slot2/port1/PFI0' for the clock terminal in your connection table, and you ought to have more luck.

Hope that helps!

Chris

Message has been deleted

Chris Billington

unread,
Nov 17, 2021, 5:51:18 PM11/17/21
to labscri...@googlegroups.com
Hi Padia,

No, you shouldn't have to configure anything additional in NI MAX or otherwise - labscript should do all that. It is attempting to do so in the configuration of the analog task which results in the error you are seeing.

The remaining error you're getting is because the terminal name is not specified correctly. I'm sorry, this is my fault - I wrote it incorrectly in my previous email. It should be  'PXI1Slot2/PFI0', not 'PXI1Slot2/port1/PFI0'.

Hope your problem will be resolved after correcting that!

Regards,

Chris

On Thu, 18 Nov 2021 at 05:54, Padia Parth Kiranbhai <f2016...@alumni.bits-pilani.ac.in> wrote:
Hi Chris,

Thank you for the suggestion. I tried it, but unfortunately I am getting the same error. I dug up a little bit on this and I have two questions to ask:
1.) Do I need to explicitly configure my line1/port0 as a PFI channel on NI MAX, as you can see on the pinout page it says configure it to PFI or D I/O
2.) On googling the error, the solution on the official page mentions that the sample clock might not be configured correctly, can it be because I didn't define acquisition rate parameter to initialize PrawnBlaster?

This is just a guess, but as you can see in the error (attached) it uses the AO_task's WriteAnalogF64, however our PXIe doesn't have an analog input channel is that a problem? Is it possible to use a DO_task to write into the channel instead (sorry if it doesn't make sense, I am still understanding the workflow of the suite).

As a matter of fact, if I use NI MAX UI to acquire my pseduoclock signal it works perfectly fine (same output as seen on runviewer).

Best,
Parth
Reply all
Reply to author
Forward
0 new messages