# Can I add timesamples to tx samples

**URL:** <https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822>\
**Category:** GNU Radio\
**Created:** [February 22, 2013, 4:27am UTC](https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822 "2013-02-22T04:27:15Z")\
**Posts on this page:** 4\
**Page:** 1

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**Author:** ![Gong\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/d07c76/32.png) [@Gong\_Z](https://www.ruby-forum.com/u/Gong_Z)\
**Post date:** [February 22, 2013, 4:27am UTC](https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822/1 "2013-02-22T04:27:15Z")

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Hi,  
Considering we can get timesamples of rx samples from UHD in  
metadata,can I add timesamples to tx samples,which would be send  
together.  
Thanks.

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**Author:** ![Gong\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/d07c76/32.png) [@Gong\_Z](https://www.ruby-forum.com/u/Gong_Z)\
**Post date:** [February 22, 2013, 4:45am UTC](https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822/2 "2013-02-22T04:45:58Z")

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On 02/21/2013 09:20 PM, Gong Z. wrote:

> Hi,  
> Considering we can get timesamples of rx samples from UHD in  
> metadata,can I add timesamples to tx samples,which would be send together.  
> Thanks.

Sure thing!

This link points to some of the examples:  
[http://code.ettus.com/redmine/ettus/projects/uhd/wiki/GNU\_Radio\_UHD#Using-UHD-Software-with-GNU-Radio](http://code.ettus.com/redmine/ettus/projects/uhd/wiki/GNU_Radio_UHD#Using-UHD-Software-with-GNU-Radio)

And here is a project that uses the timestamps to do TDMA:  
[https://github.com/jmalsbury/pre-cog/wiki](https://github.com/jmalsbury/pre-cog/wiki)

-josh

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<div class="post-metadata">

**Author:** ![Gong\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/d07c76/32.png) [@Gong\_Z](https://www.ruby-forum.com/u/Gong_Z)\
**Post date:** [February 22, 2013, 2:31pm UTC](https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822/3 "2013-02-22T14:31:59Z")

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2013/2/22 11:44, Josh B. wrote:

> 

[http://code.ettus.com/redmine/ettus/projects/uhd/wiki/GNU\_Radio\_UHD#Using-UHD-Software-with-GNU-Radio](http://code.ettus.com/redmine/ettus/projects/uhd/wiki/GNU_Radio_UHD#Using-UHD-Software-with-GNU-Radio)

> And here is a project that uses the timestamps to do TDMA:  
> [https://github.com/jmalsbury/pre-cog/wiki](https://github.com/jmalsbury/pre-cog/wiki)
> 
> -josh

Do the timesamples record the time rx/tx samples going through AD/DA in  
USRP(FPGA)?

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<div class="post-metadata">

**Author:** ![Gong\_Z](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/g/d07c76/32.png) [@Gong\_Z](https://www.ruby-forum.com/u/Gong_Z)\
**Post date:** [February 23, 2013, 3:27am UTC](https://www.ruby-forum.com/t/can-i-add-timesamples-to-tx-samples/226822/4 "2013-02-23T03:27:22Z")

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Maybe my last replay is ambiguous.In metadata,the the time value of  
rx\_sample tags was get by the command “time.time()”.Does it mean that  
the actual time recorded in tags refer to when the sample goes through  
AD in USRP with the clock in USRP?