On Mon, Aug 23, 2010 at 1:41 PM, Marc Epard
<address@hidden> wrote:
I'm trying to simultaneously transmit and receive with a USRP2 and WBX in a C++ command line tool. I'm using txrx_wbx_raw_eth_20100608.bin and u2_rev3-20100603.bin on the USRP2 and have tried GNU Radio version 3.3.0 and 3.3.1 on the Ubuntu 10.04 host. I have a spectrum analyzer on TX/RX and an antenna on RX2.
Transmitting without receiving works fine, as does receiving without transmitting. If I attempt to do both at the same time, the receive thread gets stuck -- that is rx_samples doesn't call the rx_sample_handler so I never receive the data I'm after. The transmit thread keeps running and I can see the transmitted signal on the spectrum analyzer. I've set breakpoints in various places in the USRP2 host code and as near as I can tell, there are no packets being received (poll times out each time it's called in eth_buffer::rx_frames).
If you stop transmitting, does your RX sample stream then begin again? If so, it is because I think auto transmit switching is enabled by default with the WBX on the USRP2. I asked a question a while back as to whether or not the WBX has auto TR enabled or not by default, and how to change it, but I don't think I got an answer.
Auto TR switching basically stops the RX stream while something is in your TX buffer.
- George