Merged changes from eb/digital-wip into trunk.
[debian/gnuradio] / gnuradio-examples / python / digital / transmit_path.py
diff --git a/gnuradio-examples/python/digital/transmit_path.py b/gnuradio-examples/python/digital/transmit_path.py
new file mode 100644 (file)
index 0000000..5c40173
--- /dev/null
@@ -0,0 +1,232 @@
+#
+# Copyright 2005,2006 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., 51 Franklin Street,
+# Boston, MA 02110-1301, USA.
+# 
+
+from gnuradio import gr, gru, blks
+from gnuradio import usrp
+from gnuradio import eng_notation
+
+import copy
+import sys
+
+# from current dir
+from pick_bitrate import pick_tx_bitrate
+
+# /////////////////////////////////////////////////////////////////////////////
+#                              transmit path
+# /////////////////////////////////////////////////////////////////////////////
+
+class transmit_path(gr.hier_block): 
+    def __init__(self, fg, modulator_class, options):
+        '''
+        See below for what options should hold
+        '''
+
+        options = copy.copy(options)    # make a copy so we can destructively modify
+
+        self._verbose            = options.verbose
+        self._tx_freq            = options.tx_freq         # tranmitter's center frequency
+        self._tx_amplitude       = options.tx_amplitude    # digital amplitude sent to USRP
+        self._tx_subdev_spec     = options.tx_subdev_spec  # daughterboard to use
+        self._bitrate            = options.bitrate         # desired bit rate
+        self._interp             = options.interp          # interpolating rate for the USRP (prelim)
+        self._samples_per_symbol = options.samples_per_symbol  # desired samples/baud
+        self._fusb_block_size    = options.fusb_block_size # usb info for USRP
+        self._fusb_nblocks       = options.fusb_nblocks    # usb info for USRP
+
+        self._modulator_class = modulator_class         # the modulator_class we are using
+    
+        if self._tx_freq is None:
+            sys.stderr.write("-f FREQ or --freq FREQ or --tx-freq FREQ must be specified\n")
+            raise SystemExit
+
+        # Set up USRP sink; also adjusts interp, samples_per_symbol, and bitrate
+        self._setup_usrp_sink()
+
+        # copy the final answers back into options for use by modulator
+        options.samples_per_symbol = self._samples_per_symbol
+        options.bitrate = self._bitrate
+        options.interp = self._interp
+
+        # Get mod_kwargs
+        mod_kwargs = self._modulator_class.extract_kwargs_from_options(options)
+
+        # Set center frequency of USRP
+        ok = self.set_freq(self._tx_freq)
+        if not ok:
+            print "Failed to set Tx frequency to %s" % (eng_notation.num_to_str(self._tx_freq),)
+            raise ValueError
+    
+        # transmitter
+        self.packet_transmitter = \
+            blks.mod_pkts(fg,
+                          self._modulator_class(fg, **mod_kwargs),
+                          access_code=None,
+                          msgq_limit=4,
+                          pad_for_usrp=True)
+
+
+        # Set the USRP for maximum transmit gain
+        # (Note that on the RFX cards this is a nop.)
+        self.set_gain(self.subdev.gain_range()[0])
+
+        self.amp = gr.multiply_const_cc(1)
+        self.set_tx_amplitude(self._tx_amplitude)
+
+        # enable Auto Transmit/Receive switching
+        self.set_auto_tr(True)
+
+        # Display some information about the setup
+        if self._verbose:
+            self._print_verbage()
+
+        # Create and setup transmit path flow graph
+        fg.connect(self.packet_transmitter, self.amp, self.u)
+        gr.hier_block.__init__(self, fg, None, None)
+
+    def _setup_usrp_sink(self):
+        """
+        Creates a USRP sink, determines the settings for best bitrate,
+        and attaches to the transmitter's subdevice.
+        """
+        self.u = usrp.sink_c(fusb_block_size=self._fusb_block_size,
+                             fusb_nblocks=self._fusb_nblocks)
+        dac_rate = self.u.dac_rate();
+
+        # derive values of bitrate, samples_per_symbol, and interp from desired info
+        (self._bitrate, self._samples_per_symbol, self._interp) = \
+            pick_tx_bitrate(self._bitrate, self._modulator_class.bits_per_symbol(),
+                            self._samples_per_symbol, self._interp, dac_rate)
+        
+        self.u.set_interp_rate(self._interp)
+
+        # determine the daughterboard subdevice we're using
+        if self._tx_subdev_spec is None:
+            self._tx_subdev_spec = usrp.pick_tx_subdevice(self.u)
+        self.u.set_mux(usrp.determine_tx_mux_value(self.u, self._tx_subdev_spec))
+        self.subdev = usrp.selected_subdev(self.u, self._tx_subdev_spec)
+
+
+    def set_freq(self, target_freq):
+        """
+        Set the center frequency we're interested in.
+
+        @param target_freq: frequency in Hz
+        @rypte: bool
+
+        Tuning is a two step process.  First we ask the front-end to
+        tune as close to the desired frequency as it can.  Then we use
+        the result of that operation and our target_frequency to
+        determine the value for the digital up converter.
+        """
+        r = self.u.tune(self.subdev._which, self.subdev, target_freq)
+        if r:
+            return True
+
+        return False
+        
+    def set_gain(self, gain):
+        """
+        Sets the analog gain in the USRP
+        """
+        self.gain = gain
+        self.subdev.set_gain(gain)
+
+    def set_tx_amplitude(self, ampl):
+        """
+        Sets the transmit amplitude sent to the USRP
+        @param: ampl 0 <= ampl < 32768.  Try 8000
+        """
+        self._tx_amplitude = max(0.0, min(ampl, 32767.0))
+        self.amp.set_k(self._tx_amplitude)
+        
+    def set_auto_tr(self, enable):
+        """
+        Turns on auto transmit/receive of USRP daughterboard (if exits; else ignored)
+        """
+        return self.subdev.set_auto_tr(enable)
+        
+    def send_pkt(self, payload='', eof=False):
+        """
+        Calls the transmitter method to send a packet
+        """
+        return self.packet_transmitter.send_pkt(payload, eof)
+        
+    def bitrate(self):
+        return self._bitrate
+
+    def samples_per_symbol(self):
+        return self._samples_per_symbol
+
+    def interp(self):
+        return self._interp
+
+    def add_options(normal, expert):
+        """
+        Adds transmitter-specific options to the Options Parser
+        """
+        add_freq_option(normal)
+        if not normal.has_option('--bitrate'):
+            normal.add_option("-r", "--bitrate", type="eng_float", default=None,
+                              help="specify bitrate.  samples-per-symbol and interp/decim will be derived.")
+        normal.add_option("-T", "--tx-subdev-spec", type="subdev", default=None,
+                          help="select USRP Tx side A or B")
+        normal.add_option("", "--tx-amplitude", type="eng_float", default=12000, metavar="AMPL",
+                          help="set transmitter digital amplitude: 0 <= AMPL < 32768 [default=%default]")
+        normal.add_option("-v", "--verbose", action="store_true", default=False)
+
+        expert.add_option("-S", "--samples-per-symbol", type="int", default=None,
+                          help="set samples/symbol [default=%default]")
+        expert.add_option("", "--tx-freq", type="eng_float", default=None,
+                          help="set transmit frequency to FREQ [default=%default]", metavar="FREQ")
+        expert.add_option("-i", "--interp", type="intx", default=None,
+                          help="set fpga interpolation rate to INTERP [default=%default]")
+        expert.add_option("", "--log", action="store_true", default=False,
+                          help="Log all parts of flow graph to file (CAUTION: lots of data)")
+
+    # Make a static method to call before instantiation
+    add_options = staticmethod(add_options)
+
+    def _print_verbage(self):
+        """
+        Prints information about the transmit path
+        """
+        print "Using TX d'board %s"    % (self.subdev.side_and_name(),)
+        print "Tx amplitude     %s"    % (self._tx_amplitude)
+        print "modulation:      %s"    % (self._modulator_class.__name__)
+        print "bitrate:         %sb/s" % (eng_notation.num_to_str(self._bitrate))
+        print "samples/symbol:  %3d"   % (self._samples_per_symbol)
+        print "interp:          %3d"   % (self._interp)
+        print "Tx Frequency:    %s"    % (eng_notation.num_to_str(self._tx_freq))
+        
+
+def add_freq_option(parser):
+    """
+    Hackery that has the -f / --freq option set both tx_freq and rx_freq
+    """
+    def freq_callback(option, opt_str, value, parser):
+        parser.values.rx_freq = value
+        parser.values.tx_freq = value
+
+    if not parser.has_option('--freq'):
+        parser.add_option('-f', '--freq', type="eng_float",
+                          action="callback", callback=freq_callback,
+                          help="set Tx and/or Rx frequency to FREQ [default=%default]",
+                          metavar="FREQ")