On Thu, Nov 30, 2006 at 12:15:59PM -0400, Ryan Seal wrote: > I have been working on a wxWidget based oscilloscope/spectrum widget and > have a few questions: > > First, let me cover my idea of an oscilloscope/FFT program: > > 1. Data is provided from a source (USRP or file).
> 2. Data is formatted to fit the plotting window (transform matrix). > 3. Data is sent to the plotting widget at specified intervals for display. > I am a little confused as to how this should be handled when converted > to Python. I could write 2 or 3 classes and let the main plotting widget > handle the entire show; or I could break this up and a small Python > module would combine these objects separately. To me, I view this as a > "sinking" object and a single widget would provide everything. Seems reasonable to me. It's a sink, it accepts "records" (vectors) of data and plots them. > But I don't want to continue without some sort of feedback. At this > point, I have a resizable window with ticks, a grid, and a few > labels and have plotted some test data and am happy with the > performance so far. > A few more specific questions: > > 1. Where/How do I access the USRP data stream (at the C++ level) and is > the data buffered in a way (P/C model) that allows me to know which > buffer is being filled and which one is ready to be read, overflows, > underflows, etc...? Have you looked at http://www.gnu.org/software/gnuradio/doc/howto-write-a-block.html It spells out the basics of writing a new C++ block. > 2. Is there a standard data type (at the C++ level) that I should be > using when loading/manipulating the data ( valarray, vector, pointers, > gr_xxxxx, etc...)? See howto-write-a-block. > 3. Is wxWidgets pretty much the standard for GNURadio development? It is at this point, but there are folks talking about Qt and/or PyQt. I have yet to see any code ;) > I have been looking around at other toolkits trying to find a good reason > to move from QT (for various reasons) and it appears that FLTK is > gaining momentum with other groups. Has anyone considered this? Or are > there compatibility reasons for not going this route? Independent of the conversation about a move to Qt or not, we do need a faster plot widget for wxPython. > I am concerned with the C++ aspect of the USRP because I want to > integrate this card with my current system for use with radar (305-m > dish). I currently use another card (overpriced garbage IMHO) that dumps > blocks of data into shared memory (up to 40MBPS) and I can then run > multiple processes capable of processing, storing, viewing data in > real-time. I should be able to replace the current digital receiver card > with the USRP (assuming I modify the FPGA to provide a triggered mode) > and dump this data in a similar manner. Sounds doable. I'm not sure that I really answered your questions. If I missed the mark, please ask again. Eric _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
