# GRC USRP source/sink block - IP address **URL:** \ **Category:** GNU Radio\ **Created:** [October 18, 2013, 3:07pm UTC](https://www.ruby-forum.com/t/grc-usrp-source-sink-block-ip-address/246449 "2013-10-18T15:07:44Z")\ **Posts on this page:** 3\ **Page:** 1
**Author:** ![Rafa\_F](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/r/958977/32.png) [@Rafa\_F](https://www.ruby-forum.com/u/Rafa_F)\ **Post date:** [October 18, 2013, 3:07pm UTC](https://www.ruby-forum.com/t/grc-usrp-source-sink-block-ip-address/246449/1 "2013-10-18T15:07:44Z")
Hello all just looking for some help regarding the USRP N210 in GRC. I’m having a problem with the IP address in GRC. I have looked around but the only material I have found regarding IP address relates to setting up the N210 on the network. That part I have correct. → I can ping the device → uhd\_find\_devices returns as it should → utilitiy programs (txrx\_loopback) work My problem I think is in integration with GRC. I have an existing flow that implements my OFDM system (loopback to same device) that I was using with my USRP1. All I have done after swapping in the N210 into the loop is populate the fields in the USRP sink/source block with the N210’s address. I get the following error complaining about the IP address: ///////////////////////////////////////////////////////////////////////// Traceback (most recent call last): File “transmitter\_gain\_freq\_test.py”, line 226, in tb = transmitter\_gain\_freq\_test() File “transmitter\_gain\_freq\_test.py”, line 111, in **init** channels=range(1), File “/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/ **init**.py”, line 116, in constructor\_interceptor return old\_constructor(\*args) File “/usr/local/lib/python2.7/dist-packages/gnuradio/uhd/uhd\_swig.py”, line 2479, in usrp\_source return \_uhd\_swig.usrp\_source(\*args) RuntimeError: unknown key format: 192.168.10.2 ///////////////////////////////////////////////////////////////////////// The generated code is as follows: ``` self.uhd_usrp_source_0 = uhd.usrp_source( device_addr="192.168.10.2", stream_args=uhd.stream_args( cpu_format="fc32", channels=range(1), ), ) self.uhd_usrp_source_0.set_time_now(uhd.time_spec(time.time()), ``` uhd.ALL\_MBOARDS) self.uhd\_usrp\_source\_0.set\_samp\_rate(samp\_rate) self.uhd\_usrp\_source\_0.set\_center\_freq(carrier, 0) self.uhd\_usrp\_source\_0.set\_gain(RX\_gain, 0) self.uhd\_usrp\_source\_0.set\_antenna(“RX”, 0) With the remaining fields blank or default (works with USRP1) System: ubuntu 12.10 GNU radio 3.6.5.1 I’m rather stumped here, any suggestions of change would be much appreciated. port number perhaps? Alex B – View this message in context: [http://gnuradio.4.n7.nabble.com/GRC-USRP-source-sink-block-IP-address-tp44233.html](http://gnuradio.4.n7.nabble.com/GRC-USRP-source-sink-block-IP-address-tp44233.html) Sent from the GnuRadio mailing list archive at [Nabble.com](http://Nabble.com). ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [October 18, 2013, 3:55pm UTC](https://www.ruby-forum.com/t/grc-usrp-source-sink-block-ip-address/246449/2 "2013-10-18T15:55:04Z")
On Fri, Oct 18, 2013 at 06:06:16AM -0700, Alexander B wrote: > That part I have correct. > → I can ping the device > → uhd\_find\_devices returns as it should > → utilitiy programs (txrx\_loopback) work > > My problem I think is in integration with GRC. You need to specify addr=“IP”, not just the IP (otherwise, UHD doesn’t know you want to use ethernet). > The generated code is as follows: > > ``` > self.uhd_usrp_source_0 = uhd.usrp_source( > device_addr="192.168.10.2", > > ``` ``` That's wrong ^^^^^^^^^^^^^ ``` MB – Karlsruhe Institute of Technology (KIT) Communications Engineering Lab (CEL) Dipl.-Ing. Martin B. Research Associate Kaiserstraße 12 Building 05.01 76131 Karlsruhe Phone: +49 721 608-43790 Fax: +49 721 608-46071 www.cel.kit.edu KIT – University of the State of Baden-Württemberg and National Laboratory of the Helmholtz Association ---
**Author:** ![casper\_the\_ghost](https://www.ruby-forum.com/letter_avatar_proxy/v4/letter/c/58956e/32.png) [@casper\_the\_ghost](https://www.ruby-forum.com/u/casper_the_ghost)\ **Post date:** [October 18, 2013, 4:12pm UTC](https://www.ruby-forum.com/t/grc-usrp-source-sink-block-ip-address/246449/3 "2013-10-18T16:12:01Z")
Thanks for the reply Martin yeah I got it now. I had actually tried that but I put: addr=“192.168.10.2” in the address field where it should be: addr=192.168.10.2 Thanks again Alex B – View this message in context: [http://gnuradio.4.n7.nabble.com/GRC-USRP-source-sink-block-IP-address-tp44233p44236.html](http://gnuradio.4.n7.nabble.com/GRC-USRP-source-sink-block-IP-address-tp44233p44236.html) Sent from the GnuRadio mailing list archive at [Nabble.com](http://Nabble.com).