I can't get the output to the fm_tx_2_daughterbaords.py example to work. I am testing with 2 complex signals and on each signal, the I channel is a sinusoid and the Q channel is a sinusoid of a different frequency. I have connected each of the 4 SMA connectors from the 2 Basic TX daughterboards to a different channel on an oscope. I expect to see a sinusoid on each channel but that is not the case. I see some weird waveform on the different channels on the oscope. Originally I didn't think the TX mux was set correct because the comments at the beginning of the example says that it transmits SSB (USB) and that is not what I'm looking for. I want each of the 4 different waveforms (2 sines on the I's and 2 sines on the Q's, all with different frequencies) to come out of the 4 SMA connectors. Any help would be greatly appreciated.
Thanks, Nick ----- Original Message ----- From: Eric Blossom <[EMAIL PROTECTED]> Date: Wednesday, March 21, 2007 9:45 pm Subject: Re: [Discuss-gnuradio] Question about Basic TX/RX boards, the I, Q > On Wed, Mar 21, 2007 at 05:31:36PM -0400, [EMAIL PROTECTED] wrote: > > > Thanks again for the help. I think I better understand how to set > > the RX mux. I am now working on the multi_file.py example to > > receive using 2 daughterboards on the same USRP. I want to do the > > same type of thing using 2 antennas where RX-A and RX-B (on side A) > > will receive signal 1's I and Q and RX-A and RX-B (on side B) will > > receive signal 2's I and Q. If my understanding is correct, I would > > set the mux to (0x32103210). Let me know if this is not correct. > > Correct. > > > My question now comes on the TX side. I don't quite understand how > > to set the TX mux. I want to transmit using 2 daughterboards on 1 > > USRP so I am using the fm_tx_2_daughterboards.py example. I want > > daughterboard 1 to transmit the I (RX-A) and Q (RX-B) of signal 1 > > and daughterboard 2 to transmit the I (RX-A) and Q (RX-B) of signal > > 2. This example uses the command: > > > > self.u.set_mux(0xba98) > > > > which I don't think is right for what I want to do, but I don't > > really understand how to set the TX mux in the same way I understand > > how to set the RX mux (it seems to be different). How would I set > > the TX mux to do what I want? > > self.u.set_mux(0xba98) ;) > > It is different, it's the Tx mux, not the Rx mux... > > /*! > * \brief Set output mux configuration. > * > * <pre> > * 3 2 1 > > * 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 1 0 9 8 7 6 5 4 3 2 > 1 0 > * +-------------------------------+-------+-------+-------+---- > ---+ > * | | DAC3 | DAC2 | DAC1 | > DAC0 | > * +-------------------------------+-------+-------+-------+---- > ---+ > * > * There are two interpolators with complex inputs and outputs. > * There are four DACs. > * > * Each 4-bit DACx field specifies the source for the DAC and > * whether or not that DAC is enabled. Each subfield is coded > * like this: > * > * 3 2 1 0 > * +-+-----+ > * |E| N | > * +-+-----+ > * > * Where E is set if the DAC is enabled, and N specifies which > * interpolator output is connected to this DAC. > * > * N which interp output > * --- ------------------- > * 0 chan 0 I > * 1 chan 0 Q > * 2 chan 1 I > * 3 chan 1 Q > * </pre> > */ > bool set_mux (int mux); > > > > Thanks > > Nick > > You're welcome! > > Eric > _______________________________________________ Discuss-gnuradio mailing list Discuss-gnuradio@gnu.org http://lists.gnu.org/mailman/listinfo/discuss-gnuradio
