On Wed, Jan 21, 2009 at 09:50:41PM -0500, Paul Creekmore wrote: > Eric Blossom wrote: >> On Wed, Jan 21, 2009 at 05:47:19PM -0500, Paul Creekmore wrote: >> >> >> Thanks for answering your own question :-) >> >> The USRP1 is little endian. My not-fully-considered thought is that it >> ought to go like this (everything packed into a 32-bit word): >> >> 16 bit I & Q (same as today): >> >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> | Q0 | I0 | >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> >> 8 bit I & Q (different from today: see usrp_source_c.cc): >> >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> | Q1 | I1 | Q0 | I0 | >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> >> 4 bit I & Q: >> >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> | Q3 | I3 | Q2 | I2 | Q1 | I1 | Q0 | I0 | >> +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+ >> >> etc... >> >> What are you thoughts about this? >> >> Eric >> > First off, current USRP words are 16-bit, are they not? The rx_buffer > module in the FPGA code stores data in a 16-bit FIFO. Are you > suggesting changing this, or is the 32-bit width above merely > illustrative?
illustrative. > Either way, I agree with your sample ordering above. > It's consistent for all sample widths, and it should make host-side code > straight-forward. OK, good. "Make it so" :-) Eric g _______________________________________________ Discuss-gnuradio mailing list [email protected] http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
