Merged r6271:6278 from jcorgan/t182 into trunk. Implements ticket:182.

Created new top-level component, gr-utils, to hold commonly used utility
scripts (originally in gnuradio-examples).  These now install into the 
system path, allowing their use from wherever.

Reorganization of gnuradio-examples component:

 * Commonly used utility scripts moved from python/usrp into gr-utils.
 * Examples now install into $(prefix)/share/gnuradio/examples/...
 * Channel coding examples moved into gr-trellis/src/examples, now install
   from there, only if gr-atsc itself is going to built and installed.
 * ATSC example scripts now install into example hierarchy
 * Cruft has been moved into 'limbo' in repository, do not get installed

Trunk passes 'make distcheck'.



git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@6279 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 106 insertions, 0 deletions

diff --git a/gr-utils/src/python/usrp_benchmark_usb.py b/gr-utils/src/python/usrp_benchmark_usb.py
new file mode 100755
index 000000000..fc01514a1
--- /dev/null
+++ b/gr-utils/src/python/usrp_benchmark_usb.py
@@ -0,0 +1,106 @@
+#!/usr/bin/env python
+#
+# Copyright 2004,2005 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 3, 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., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+"""
+Benchmark the USB/USRP throughput.  Finds the maximum full-duplex speed
+the USRP/USB combination can sustain without errors.
+
+This program does not currently give reliable results.  Sorry about that...
+"""
+
+from gnuradio import gr
+from gnuradio import usrp
+from gnuradio import eng_notation
+
+import sys
+
+def run_test (usb_throughput, verbose):
+    # usb_throughput is in bytes/sec.
+    #
+    # Returns True or False
+    
+    nsec = 1
+    stream_length = int (usb_throughput/2 * nsec)   # length of stream to examine
+
+    adc_freq =  64e6
+    dac_freq = 128e6
+    sizeof_sample = 2 * gr.sizeof_short
+
+    usb_throughput_in_samples = usb_throughput / sizeof_sample
+
+    # allocate usb throughput 50/50 between Tx and Rx
+
+    tx_interp = int (dac_freq) / int (usb_throughput_in_samples / 2)
+    rx_decim  = int (adc_freq) / int (usb_throughput_in_samples / 2)
+
+    # print "tx_interp =", tx_interp, "rx_decim =", rx_decim
+    assert (tx_interp == 2 * rx_decim)
+    
+    fg = gr.flow_graph ()
+
+    # Build the Tx pipeline
+    data_src = gr.lfsr_32k_source_s ()
+    src_head = gr.head (gr.sizeof_short, int (stream_length * 2))
+    usrp_tx = usrp.sink_s (0, tx_interp)
+    fg.connect (data_src, src_head, usrp_tx)
+
+    # and the Rx pipeline
+    usrp_rx = usrp.source_s (0, rx_decim, 1, 0x32103210, usrp.FPGA_MODE_LOOPBACK)
+    head = gr.head (gr.sizeof_short, stream_length)
+    check = gr.check_lfsr_32k_s ()
+    fg.connect (usrp_rx, head, check)
+
+    fg.run ()
+
+    ntotal = check.ntotal ()
+    nright = check.nright ()
+    runlength = check.runlength ()
+
+    if verbose:
+        print "usb_throughput =", eng_notation.num_to_str (usb_throughput)
+        print "ntotal    =", ntotal
+        print "nright    =", nright
+        print "runlength =", runlength
+        print "delta     =", ntotal - runlength
+
+    return runlength >= stream_length - 80000
+    
+def main ():
+    verbose = True
+    best_rate = 0
+    usb_rate = [ 2e6, 4e6, 8e6, 16e6, 32e6 ]
+    #usb_rate = [ 32e6, 32e6, 32e6, 32e6, 32e6 ]
+    # usb_rate.reverse ()
+    for rate in usb_rate:
+        sys.stdout.write ("Testing %sB/sec... " % (eng_notation.num_to_str (rate)))
+        sys.stdout.flush ()
+        ok = run_test (rate, verbose)
+        if ok:
+            best_rate = max (best_rate, rate)
+            sys.stdout.write ("OK\n")
+        else:
+            sys.stdout.write ("FAILED\n")
+
+    print "Max USB/USRP throughput = %sB/sec" % (eng_notation.num_to_str (best_rate),)
+
+if __name__ == '__main__':
+    main ()