# MIMO setup error in GRC

**URL:** <https://www.ruby-forum.com/t/mimo-setup-error-in-grc/224060>\
**Category:** GNU Radio\
**Created:** [October 28, 2012, 11:01pm UTC](https://www.ruby-forum.com/t/mimo-setup-error-in-grc/224060 "2012-10-28T23:01:38Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![aris](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/258eb7/32.png) [@aris](https://www.ruby-forum.com/u/aris)\
**Post date:** [October 28, 2012, 11:01pm UTC](https://www.ruby-forum.com/t/mimo-setup-error-in-grc/224060/1 "2012-10-28T23:01:38Z")

</div>

Hi,

Does anyone know about the following error?

File “/export/home/usrp2/gnuradio-3.6.0/MyGRC/top\_block.py”, line 52, in  
**init**  
self.uhd\_usrp\_source\_0.set\_clock\_source(“mimo”, 1)  
File  
“/usr/local/lib/python2.6/dist-packages/gnuradio/uhd/uhd\_swig.py”,  
line 1915, in set\_clock\_source  
return \_uhd\_swig.uhd\_usrp\_source\_sptr\_set\_clock\_source(self, \*args,  
\*\*kwargs)  
RuntimeError: vector::\_M\_range\_check

I am trying to setup a simple MIMO reception with N210+WBX boards in  
GRC.  
My MIMO connection is all ok since I can see both devices attached by  
running “uhd\_find\_devices” and “uhd\_usrp\_probe”. My GRC has a [uhd: usrp  
source] block configured to have 2 Mboards one having default time and  
clock and the other having MIMO as its reference. Basically I have  
configured it the same as the model in Ettus’s Application Note on MIMO  
and  
synchronization. But I’ll get the error above at run-time.

Any help is very much appreciated!

Thanks,  
Alex

---

<div class="post-metadata">

**Author:** ![Alex\_Dusowitz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/258eb7/32.png) [@Alex\_Dusowitz](https://www.ruby-forum.com/u/Alex_Dusowitz)\
**Post date:** [October 28, 2012, 11:08pm UTC](https://www.ruby-forum.com/t/mimo-setup-error-in-grc/224060/2 "2012-10-28T23:08:04Z")

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On 10/28/2012 06:00 PM, Alex Dusowitz wrote:

> “/usr/local/lib/python2.6/dist-packages/gnuradio/uhd/uhd\_swig.py”,  
> default time and clock and the other having MIMO as its reference.  
> Basically I have configured it the same as the model in Ettus’s  
> Application Note on MIMO and synchronization. But I’ll get the error  
> above at run-time.
> 
> Any help is very much appreciated!
> 
> Thanks,  
> Alex

Given that you’re running a fairly-old version of GNu Radio, I’m pretty  
confident that you’re running a fairly-old version of UHD as well.

Upgrade both, and see if the error persists. I think you may find that  
it doesn’t.

---

<div class="post-metadata">

**Author:** ![Alex\_Dusowitz](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/a/258eb7/32.png) [@Alex\_Dusowitz](https://www.ruby-forum.com/u/Alex_Dusowitz)\
**Post date:** [October 29, 2012, 7:35pm UTC](https://www.ruby-forum.com/t/mimo-setup-error-in-grc/224060/3 "2012-10-29T19:35:43Z")

</div>

On 10/28/2012 03:00 PM, Alex Dusowitz wrote:

> \*\*kwargs)  
> RuntimeError: vector::\_M\_range\_check

So thats a vector index of of range error:  
self.uhd\_usrp\_source\_0.set\_clock\_source(“mimo”, 1)

Perhaps the device is not configured for two motherboards? What was your  
device address? You may find an example for this in the GRC properties  
dialog. Something like:

addr0=192.168.10.2,addr1=192.168.10.3

-josh