-
Notifications
You must be signed in to change notification settings - Fork 79
New issue
Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.
By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.
Already on GitHub? Sign in to your account
struct.pack error at low sample rates #110
Comments
Seems to be good for rates from 1 to 822 Hz (haven't checked exhaustively), then bad for the following (inclusive) ranges:
The pack error is only ever on the first retrieval from the streamData generator after its construction; subsequent
|
I haven't been able to reproduce the struct.error on Windows, Linux or Mac. What operating system and its version are you using? What firmware version is on your U6 (check with the configU6 method)? If you power cycle your U6 and run your code, does it have the same issue? |
Firmware v 1.39. |
I still see the issue with the latest firmware, 1.45 |
#111 is a one-line change that prevents the error, and the data looks good - if I configure FIO0 as a frequency output and sample it, I see no discontinuities or spurious points. |
PR #111 looks similar to #106, which was previously rejected because the author did not respond to requests for more information. Thankfully @mickp has been very active on this ticket so hopefully the issue can be troubleshot and resolved this time around. |
Yeah - #106 is the same behaviour change, to address the same issue. I've been unable to figure out the underlying cause (why are too few bytes being read?), but the workaround delivers what I believe to be the expected behaviour. |
Thanks for the additional information. I'll see if I can reproduce your issue before accepting your commit. As for the too few bytes being read, that would occur with the 1 second USB timeout and all requested data not being available. Responses come in 64-byte packets, so with your error the last packet wasn't available within the timeout period. Likely with a small delay after the stream start you wouldn't get the error. |
@mickp , I made a commit to help prevent the partial stream read packets. Please try out the latest LabJackPython here on GitHub and let me know if this resolves your issue or not. I didn't use your pull request's solution as I wanted to prevent the partial reads, and that error lets me know when stream code relating to read sizes needs fixing/tweaking. |
Yep - that fixes things here. |
Thanks. I'm going to close this out. |
Running
yields the following traceback
The text was updated successfully, but these errors were encountered: