# Publishing and reading uORB topics to and from a queue

**URL:** <https://discuss.px4.io/t/publishing-and-reading-uorb-topics-to-and-from-a-queue/5430>\
**Category:** Uncategorized\
**Created:** [January 15, 2018, 10:25am UTC](https://discuss.px4.io/t/publishing-and-reading-uorb-topics-to-and-from-a-queue/5430 "2018-01-15T10:25:43Z")\
**Posts on this page:** 1\
**Page:** 1

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**Author:** ![ksschwabe](https://discuss.px4.io/letter_avatar_proxy/v4/letter/k/b782af/32.png) [@ksschwabe](https://discuss.px4.io/u/ksschwabe)\
**Post date:** [January 15, 2018, 10:25am UTC](https://discuss.px4.io/t/publishing-and-reading-uorb-topics-to-and-from-a-queue/5430/1 "2018-01-15T10:25:43Z")

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I am trying to log some changes to (non-Px4) parameters on my board. I have created a uORB topic which I publish whenever I vary these parameters.

When trying to read the uORB topic in order to log each and every parameter change, I do not know how to check how many uORB messages are queued, or how to read them all out correctly. If I use to the usual `orb_check()` and `orb_copy()` approach I only get the latest changed published message read out from the uORB and I miss the others messages that were published just before it in the loop.

Any pointers/help would be appreciated.