[Discuss-gnuradio] dumb question: history
How does 'history' relate to i/o data indices? I assume you cannot have an index zero. Say your work function gets common i/o arrays const float *in = (const float *) input_items[0]; float *out = (float *) output_items[0]; and you set_history(ntaps), I guess that means you get ( noutput_items + ntaps ) for the number of intput items and can produce noutput_items output. Now I have two streams, one is pass-thru (symbol tags) and the other is the data to be filtered and gets delayed by ntaps. The filtered stream is processed by: d_equalizer-filter (in, in_tags, out, noutput_items); where out[x] is the processed sample in[x + ntaps] (?). So to keep the symbol tags aligned, should we use: for (int i = 0; i noutput_items; i++) out_tags[i] = in_tags[i + d_offset]; d_offset = ntaps - npretaps - 1 Is that the correct thinking? size of out[] is noutput_items and size of in[] is noutput_items + history ?? history = ntaps, and is ntaps ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] GNU Radio TCP and MATLAB
Hello again, I have decided to try the GNURadio - TCP - MATLAB route. I am running into a few problems. First, I downloaded Jamie Cooley's GNURadio TCP Socket code here... http://alumni.media.mit.edu/~jcooley/gr_experiments/experiments/gr_socket.ht m Then I downloaded a free matlab TCP toolbox as David suggested. http://www.mathworks.nl/matlabcentral/fileexchange/loadFile.do?objectId=345; objectType=file I can set up the connection and send data to matlab, but the data I receive is all messed up. I think the format is off. For those who have done this, what data type are you sending and how are you receiving it? Currently, I am just sending a complex sine wave. If I sink it to a file, I can open it in matlab with no problem. But when I send it via TCP, I get garbage. My matlab commands are basically... Con = pnet(sock,'tcplisten'); data = pnet(con, 'read', 1000, 'SINGLE'); cdata = data(1:2:end)+j*data(2:2:end); plot(log(abs(fft(cdata Is 'SINGLE' the correct type to use? (I tried all the others and I still get gargabe). Thanks for the help, Kevin ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNU Radio TCP and MATLAB
On Thu, Apr 26, 2007 at 12:52:40PM -0400, Kevin Rudd (Contractor) wrote: Hello again, I have decided to try the GNURadio - TCP - MATLAB route. I am running into a few problems. First, I downloaded Jamie Cooley's GNURadio TCP Socket code here... http://alumni.media.mit.edu/~jcooley/gr_experiments/experiments/gr_socket.htm Then I downloaded a free matlab TCP toolbox as David suggested. http://www.mathworks.nl/matlabcentral/fileexchange/loadFile.do?objectId=345; objectType=file I can set up the connection and send data to matlab, but the data I receive is all messed up. I think the format is off. For those who have done this, what data type are you sending and how are you receiving it? Currently, I am just sending a complex sine wave. If I sink it to a file, I can open it in matlab with no problem. But when I send it via TCP, I get garbage. My matlab commands are basically... Con = pnet(sock,'tcplisten'); data = pnet(con, 'read', 1000, 'SINGLE'); cdata = data(1:2:end)+j*data(2:2:end); plot(log(abs(fft(cdata Is 'SINGLE' the correct type to use? (I tried all the others and I still get gargabe). Thanks for the help, Kevin Not sure about the MATLAB end of things, but gr.file_descriptor_sink will be sending binary native-endian data. The format will depend on what you're sending into it. float or gr_complex (== std::complexfloat) are the usual suspects. Is the MATLAB code expecting binary or ASCII data? Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] FX2 TX DMA Transfer Question
When the FX2 detects the have_space pin on the FPGA, does it transfer 1 entire buffered USB packet to the FPGA, then re-check the have_space pin? Would it be reasonable to assume a 1 clock delay between the last byte of one 512-byte packet being written to the FPGA and the first byte of a second 512-byte packet being written to the FPGA? Thanks, Brian ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] FX2 TX DMA Transfer Question
On Thu, Apr 26, 2007 at 01:56:10PM -0400, Brian Padalino wrote: When the FX2 detects the have_space pin on the FPGA, does it transfer 1 entire buffered USB packet to the FPGA, then re-check the have_space pin? Yes. Would it be reasonable to assume a 1 clock delay between the last byte of one 512-byte packet being written to the FPGA and the first byte of a second 512-byte packet being written to the FPGA? Yes. That shouldn't be a problem. There's software inside the FX2 that polls the pin. You've got at least 100 ns between packets, probably more. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] GNU Radio TCP and MATLAB
On Thu, Apr 26, 2007 at 02:48:34PM -0400, Kevin Rudd (Contractor) wrote: Thanks for the suggestion. I dove into the TCP code to try and figure out what it was doing. I found my problem. I have to use the following read command... data = pnet(con, 'read', 1000, 'SINGLE', 'NATIVE'); Now I notice that matlab seems to be lag behind the USRP. So, maybe matlab is not the best path to process the data in realtime. I am curious what the best data rate someone has sustained using a TCP connection. TCP on GigE can do upwards of 100MB/s ;) If I get it up and going, I will post my code and a howto so others can stream data to and from MATLAB in real time. Thanks. Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] What is the typical max USB transfer rate from the URSP?
I got my USRP running today. The first test I ran was the usb speed test in the examples/usrp folder. It will do up to 16MB/s. The 32 MB/s transfer fails. This is a dual Opteron system with 4G of memory running Suse 10.1. Any advise on getting to 32 MB/s. I don't remember what chipset is on the USB2.0 card but I do remember that I choose it specifically because it had good Linux support. NEC maybe?? Thanks, Jim ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
[Discuss-gnuradio] Newbe: Jerky sound with usrp_wfm_rcv.py
I finally got the usrp up and running. I am having two problems. 1. I believe that the data rate is overflowing the usb line becuase the sound from usrp_wfm_rcv.py is jerky and the text UaUaUaUaUa... is streaming to the screen (about 1-2 times per second). I am running the pre-compiled packages available through Ubuntu on a Dell inspiron 1501 1.6 GHz processor. Would compiling from scratch help? Is there a way to decimate the data before it comes across the usb? 2. I need to unplug and plug the usrp after each use otherwise I get the error RuntimeError: Unable to find USRP #0. Cycling the power is the only work around I have at this point. Any suggestions on how to fix this one? Full disclosure: I had to copy the files from /usr/local/share/usrp/Rev* to /usr/share/usrp to get the firmware to automatically load do I need to do anything else? Thanks for any help or advice. Justin Shaw ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] What is the typical max USB transfer rate from the URSP?
On Thu, Apr 26, 2007 at 09:07:33PM -0500, Jim Perkins wrote: Unfortunately the motherboard does not have USB2.0 built in. Why do the add-in cards have a speed issue? -Jim Why do chip designers design lame chips? Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
Re: [Discuss-gnuradio] Newbe: Jerky sound with usrp_wfm_rcv.py
On Thu, Apr 26, 2007 at 10:22:46PM -0400, Justin Shaw wrote: Matt Ettus wrote: Justin Shaw wrote: ... sound from usrp_wfm_rcv.py is jerky and the text UaUaUaUaUa... Use the following option to usrp_wfm_rcv.py: -O plughw:0,0 And see if that helps. Yup, that did the trick, thanks. 2. I need to unplug and plug the usrp after each use otherwise I get the error RuntimeError: Unable to find USRP #0. Cycling the power is the only work around I have at this point. Any suggestions on how to fix this one? Full disclosure: I had to copy the files from /usr/local/share/usrp/Rev* to /usr/share/usrp to get the firmware to automatically load do I need to do anything else? I think this is a recent Ubuntu problem. Which version do you use? It was a fresh install just for this project: gnuradio, usrp ... 3.0.2-2 Ununtu 7.04 I'm working on this problem... Eric ___ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
