Re-implemented variable sink so that it can pass vector-aligned samples.

Created backend grc blks2 block to sample the stream and set callback.
Renamed variable sink and moved it into the sinks category.
Added example of variable sink reading taps from a stream and setting them to a FIR filter.



git-svn-id: http://gnuradio.org/svn/gnuradio/trunk@11062 221aa14e-8319-0410-a670-987f0aec2ac5

1 files changed, 64 insertions, 0 deletions

diff --git a/grc/src/grc_gnuradio/blks2/variable_sink.py b/grc/src/grc_gnuradio/blks2/variable_sink.py
new file mode 100644
index 000000000..cad3b8b04
--- /dev/null
+++ b/grc/src/grc_gnuradio/blks2/variable_sink.py
@@ -0,0 +1,64 @@
+#
+# Copyright 2009 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.
+#
+
+from gnuradio import gr
+import threading
+import numpy
+
+class _variable_sink_base(gr.hier_block2, threading.Thread):
+	"""
+	The thread polls the message queue for values and writes to a callback.
+	"""
+
+	def __init__(self, vlen, decim, callback):
+		self._vlen = vlen
+		self._callback = callback
+		self._item_size = self._size*self._vlen
+		#init hier block
+		gr.hier_block2.__init__(
+			self, 'variable_sink',
+			gr.io_signature(1, 1, self._item_size),
+			gr.io_signature(0, 0, 0),
+		)
+		#create blocks
+		self._decimator = gr.keep_one_in_n(self._item_size, decim)
+		self._msgq = gr.msg_queue(2)
+		message_sink = gr.message_sink(self._item_size, self._msgq, False)
+		#connect
+		self.connect(self, self._decimator, message_sink)
+		#setup thread
+		threading.Thread.__init__(self)
+		self.setDaemon(True)
+		self.start() 
+
+	def set_decim(self, decim): self._decimator.set_n(decim)
+
+	def run(self):
+		while True: #truncate to item size, convert to array, callback
+			msg = self._msgq.delete_head().to_string()[-self._item_size:]
+			arr = map(self._cast, numpy.fromstring(msg, self._numpy))
+			self._callback(self._vlen > 1 and arr or arr[0])
+
+class variable_sink_b(_variable_sink_base): _numpy, _size, _cast = numpy.int8, gr.sizeof_char, int
+class variable_sink_s(_variable_sink_base): _numpy, _size, _cast = numpy.int16, gr.sizeof_short, int
+class variable_sink_i(_variable_sink_base): _numpy, _size, _cast = numpy.int32, gr.sizeof_int, int
+class variable_sink_f(_variable_sink_base): _numpy, _size, _cast = numpy.float32, gr.sizeof_float, float
+class variable_sink_c(_variable_sink_base): _numpy, _size, _cast = numpy.complex64, gr.sizeof_gr_complex, complex