[Discuss-gnuradio] Receiving from Rx-A and Rx-B of a single daughterboard

[Felipe Fideles]

Hello, all.

We are developing a program that uses Rx-A and Rx-B. Rx-A is used to sense the spectrum and, after that, Rx-B to receive FM signals. Is it only possible to use A and B simultaneously in a program using one USRP? 

First, the program call Rx-A. After some time, Rx-B is called and the error below is given:

usrp_open_interface:usb_claim_interface: failed interface 2
could not claim interface 2: busy
usrp_basic_rx: can't open rx interface

Traceback (most recent call last):
  File "/home/ed02/Documentos/usrp_wfm_rcv.py", line 304, in <module>
    app = stdgui2.stdapp (wfm_rx_block, "USRP WFM RX")
  File "/usr/lib/python2.6/dist-packages/gnuradio/wxgui/stdgui2.py", line 36, in __init__

    wx.App.__init__ (self, redirect=False)
  File "/usr/lib/python2.6/dist-packages/wx-2.8-gtk2-unicode/wx/_core.py", line 7935, in __init__
    self._BootstrapApp()
  File "/usr/lib/python2.6/dist-packages/wx-2.8-gtk2-unicode/wx/_core.py", line 7509, in _BootstrapApp

    return _core_.PyApp__BootstrapApp(*args, **kwargs)
  File "/usr/lib/python2.6/dist-packages/gnuradio/wxgui/stdgui2.py", line 39, in OnInit
    frame = stdframe (self.top_block_maker, self.title, self._nstatus)

  File "/usr/lib/python2.6/dist-packages/gnuradio/wxgui/stdgui2.py", line 60, in __init__
    self.panel = stdpanel (self, self, top_block_maker)
  File "/usr/lib/python2.6/dist-packages/gnuradio/wxgui/stdgui2.py", line 81, in __init__

    self.top_block = top_block_maker (frame, self, vbox, sys.argv)
  File "/home/ed02/Documentos/usrp_wfm_rcv.py", line 82, in __init__
    self.u = usrp.source_c(which=0)                    # usrp is data source

  File "/usr/lib/python2.6/dist-packages/gnuradio/usrp/usrp_swig.py", line 1651, in source_c
    return _usrp_swig.source_c(*args, **kwargs)

RuntimeError: can't open usrp

The code is based on the programs spectrum_sense.py and usrp_wfm_rcv2.py.

How can I use Rx's A and B in a program, but not in the same time (and calling usrp_source only once)?

Thanks for your attention,

-- 
Felipe Fideles
Electrical Engineering Undergraduate Student

Federal University of Campina Grande, Brazil