1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
|
#!/usr/bin/env python
#
# Copyright 2004 Free Software Foundation, Inc.
#
# This file is part of GNU Radio
#
# GNU Radio is free software; you can redistribute it and/or modify
# it under the terms of the GNU General Public License as published by
# the Free Software Foundation; either version 2, or (at your option)
# any later version.
#
# GNU Radio is distributed in the hope that it will be useful,
# but WITHOUT ANY WARRANTY; without even the implied warranty of
# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
# GNU General Public License for more details.
#
# You should have received a copy of the GNU General Public License
# along with GNU Radio; see the file COPYING. If not, write to
# the Free Software Foundation, Inc., 59 Temple Place - Suite 330,
# Boston, MA 02111-1307, USA.
#
"""
Digital loopback (Tx to Rx) for the USRP Rev1.
"""
from gnuradio import gr
from gnuradio import usrp
def ramp_source (fg):
period = 2**16
src = gr.vector_source_s (range (-period/2, period/2, 1), True)
return src
def build_graph ():
tx_interp = 32 # tx should be twice rx
rx_decim = 16
fg = gr.flow_graph ()
data_src = ramp_source (fg)
# usrp_tx = usrp.sink_s (0, tx_interp, 1, 0x98)
usrp_tx = usrp.sink_s (0, tx_interp)
fg.connect (data_src, usrp_tx)
usrp_rx = usrp.source_s (0, rx_decim, 1, 0x32103210, usrp.FPGA_MODE_LOOPBACK)
sink = gr.check_counting_s ()
fg.connect (usrp_rx, sink)
# file_sink = gr.file_sink (gr.sizeof_short, "loopback.dat")
# fg.connect (usrp_rx, file_sink)
return fg
def main ():
fg = build_graph ()
try:
fg.run()
except KeyboardInterrupt:
pass
if __name__ == '__main__':
main ()
|
