Merge branch 'master' into 8psk

31 files changed, 315 insertions, 180 deletions

diff --git a/grc/Makefile.am b/grc/Makefile.am
index c36786281..9d473b4d3 100644
--- a/grc/Makefile.am
+++ b/grc/Makefile.am
@@ -43,7 +43,6 @@ BUILT_SOURCES += grc.conf
 
 grc.conf: $(srcdir)/grc.conf.in Makefile
 	sed \
-		-e 's|@pythonw[@]|$(PYTHONW)|g' \
 		-e 's|@blocksdir[@]|$(grc_blocksdir)|g' \
 		-e 's|@docdir[@]|$(gr_docdir)|g' \
 	$< > $@
diff --git a/grc/base/Block.py b/grc/base/Block.py
index 42eb6b3fb..fe7ad3c2f 100644
--- a/grc/base/Block.py
+++ b/grc/base/Block.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -92,8 +92,8 @@ class Block(Element):
 		for param in map(lambda n: self.get_parent().get_parent().Param(block=self, n=n), params):
 			key = param.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_param_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in params'%key
+			if key in self.get_param_keys():
+				raise Exception, 'Key "%s" already exists in params'%key
 			#store the param
 			self.get_params().append(param)
 		#create the source objects
@@ -101,8 +101,8 @@ class Block(Element):
 		for source in map(lambda n: self.get_parent().get_parent().Port(block=self, n=n, dir='source'), sources):
 			key = source.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_source_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in sources'%key
+			if key in self.get_source_keys():
+				raise Exception, 'Key "%s" already exists in sources'%key
 			#store the port
 			self.get_sources().append(source)
 		#create the sink objects
@@ -110,8 +110,8 @@ class Block(Element):
 		for sink in map(lambda n: self.get_parent().get_parent().Port(block=self, n=n, dir='sink'), sinks):
 			key = sink.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_sink_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in sinks'%key
+			if key in self.get_sink_keys():
+				raise Exception, 'Key "%s" already exists in sinks'%key
 			#store the port
 			self.get_sinks().append(sink)
 
diff --git a/grc/base/Connection.py b/grc/base/Connection.py
index 94d4751b2..3ce7fd07f 100644
--- a/grc/base/Connection.py
+++ b/grc/base/Connection.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -37,10 +37,12 @@ class Connection(Element):
 		for port in (porta, portb):
 			if port.is_source(): source = port
 			if port.is_sink(): sink = port
-		assert(source and sink)
+		if not source: raise ValueError('Connection could not isolate source')
+		if not sink: raise ValueError('Connection could not isolate sink')
 		#ensure that this connection (source -> sink) is unique
 		for connection in self.get_parent().get_connections():
-			assert not (connection.get_source() is source and connection.get_sink() is sink)
+			if connection.get_source() is source and connection.get_sink() is sink:
+				raise Exception('This connection between source and sink is not unique.')
 		self._source = source
 		self._sink = sink
 
@@ -62,8 +64,8 @@ class Connection(Element):
 		Element.validate(self)
 		source_type = self.get_source().get_type()
 		sink_type = self.get_sink().get_type()
-		try: assert source_type == sink_type
-		except AssertionError: self.add_error_message('Source type "%s" does not match sink type "%s".'%(source_type, sink_type))
+		if source_type != sink_type:
+			self.add_error_message('Source type "%s" does not match sink type "%s".'%(source_type, sink_type))
 
 	def get_enabled(self):
 		"""
diff --git a/grc/base/FlowGraph.py b/grc/base/FlowGraph.py
index b4ac8fc3a..0ba1f2389 100644
--- a/grc/base/FlowGraph.py
+++ b/grc/base/FlowGraph.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -194,18 +194,26 @@ class FlowGraph(Element):
 				sink_key = connection_n.find('sink_key')
 				#verify the blocks
 				block_ids = map(lambda b: b.get_id(), self.get_blocks())
-				assert(source_block_id in block_ids)
-				assert(sink_block_id in block_ids)
+				if source_block_id not in block_ids:
+					raise LookupError('source block id "%s" not in block ids'%source_block_id)
+				if sink_block_id not in block_ids:
+					raise LookupError('sink block id "%s" not in block ids'%sink_block_id)
 				#get the blocks
 				source_block = self.get_block(source_block_id)
 				sink_block = self.get_block(sink_block_id)
 				#verify the ports
-				assert(source_key in source_block.get_source_keys())
-				assert(sink_key in sink_block.get_sink_keys())
+				if source_key not in source_block.get_source_keys():
+					raise LookupError('source key "%s" not in source block keys'%source_key)
+				if sink_key not in sink_block.get_sink_keys():
+					raise LookupError('sink key "%s" not in sink block keys'%sink_key)
 				#get the ports
 				source = source_block.get_source(source_key)
 				sink = sink_block.get_sink(sink_key)
 				#build the connection
 				self.connect(source, sink)
-			except AssertionError: Messages.send_error_load('Connection between %s(%s) and %s(%s) could not be made.'%(source_block_id, source_key, sink_block_id, sink_key))
+			except LookupError, e: Messages.send_error_load(
+				'Connection between %s(%s) and %s(%s) could not be made.\n\t%s'%(
+					source_block_id, source_key, sink_block_id, sink_key, e
+				)
+			)
 		self.rewrite() #global rewrite
diff --git a/grc/base/Param.py b/grc/base/Param.py
index 5cd0f9d6d..c2fa5461a 100644
--- a/grc/base/Param.py
+++ b/grc/base/Param.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -34,16 +34,16 @@ class Option(Element):
 		self._opts = dict()
 		opts = n.findall('opt')
 		#test against opts when non enum
-		try: assert self.get_parent().is_enum() or not opts
-		except AssertionError: raise Exception, 'Options for non-enum types cannot have sub-options'
+		if not self.get_parent().is_enum() and opts:
+			raise Exception, 'Options for non-enum types cannot have sub-options'
 		#extract opts
 		for opt in opts:
 			#separate the key:value
 			try: key, value = opt.split(':')
 			except: raise Exception, 'Error separating "%s" into key:value'%opt
 			#test against repeated keys
-			try: assert not self._opts.has_key(key)
-			except AssertionError: raise Exception, 'Key "%s" already exists in option'%key
+			if self._opts.has_key(key):
+				raise Exception, 'Key "%s" already exists in option'%key
 			#store the option
 			self._opts[key] = value
 
@@ -79,24 +79,24 @@ class Param(Element):
 		for option in map(lambda o: Option(param=self, n=o), n.findall('option')):
 			key = option.get_key()
 			#test against repeated keys
-			try: assert key not in self.get_option_keys()
-			except AssertionError: raise Exception, 'Key "%s" already exists in options'%key
+			if key in self.get_option_keys():
+				raise Exception, 'Key "%s" already exists in options'%key
 			#store the option
 			self.get_options().append(option)
 		#test the enum options
 		if self.is_enum():
 			#test against options with identical keys
-			try: assert len(set(self.get_option_keys())) == len(self.get_options())
-			except AssertionError: raise Exception, 'Options keys "%s" are not unique.'%self.get_option_keys()
+			if len(set(self.get_option_keys())) != len(self.get_options()):
+				raise Exception, 'Options keys "%s" are not unique.'%self.get_option_keys()
 			#test against inconsistent keys in options
 			opt_keys = self.get_options()[0].get_opt_keys()
 			for option in self.get_options():
-				try: assert set(opt_keys) == set(option.get_opt_keys())
-				except AssertionError: raise Exception, 'Opt keys "%s" are not identical across all options.'%opt_keys
+				if set(opt_keys) != set(option.get_opt_keys()):
+					raise Exception, 'Opt keys "%s" are not identical across all options.'%opt_keys
 			#if a value is specified, it must be in the options keys
 			self._value = value if value or value in self.get_option_keys() else self.get_option_keys()[0]
-			try: assert self.get_value() in self.get_option_keys()
-			except AssertionError: raise Exception, 'The value "%s" is not in the possible values of "%s".'%(self.get_value(), self.get_option_keys())
+			if self.get_value() not in self.get_option_keys():
+				raise Exception, 'The value "%s" is not in the possible values of "%s".'%(self.get_value(), self.get_option_keys())
 		else: self._value = value or ''
 
 	def validate(self):
@@ -105,8 +105,8 @@ class Param(Element):
 		The value must be evaluated and type must a possible type.
 		"""
 		Element.validate(self)
-		try: assert self.get_type() in self.get_types()
-		except AssertionError: self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
+		if self.get_type() not in self.get_types():
+			self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
 
 	def get_evaluated(self): raise NotImplementedError
 
diff --git a/grc/base/Platform.py b/grc/base/Platform.py
index 096fdec41..a66c28ab9 100644
--- a/grc/base/Platform.py
+++ b/grc/base/Platform.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009, 2011 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -17,16 +17,6 @@ along with this program; if not, write to the Free Software
 Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 """
 
-#Perform python integrity checks:
-# GRC will not work with interpreters that fail the checks below.
-# This can fail on interpreters built with special optimizations.
-try:
-	assert False
-	raise Exception, 'Failed python integrity check: assert not supported'
-except AssertionError: pass
-if __doc__ is None:
-	raise Exception, 'Failed python integrity check: __doc__ not supported'
-
 import os
 import sys
 from .. base import ParseXML, odict
@@ -91,13 +81,12 @@ class Platform(_Element):
 				block = self.Block(self._flow_graph, n)
 				key = block.get_key()
 				#test against repeated keys
-				try:
-					assert key not in self.get_block_keys()
-					#store the block
+				if key in self.get_block_keys():
+					print >> sys.stderr, 'Warning: Block with key "%s" already exists.\n\tIgnoring: %s'%(key, xml_file)
+				#store the block
+				else:
 					self._blocks[key] = block
 					self._blocks_n[key] = n
-				except AssertionError:
-					print >> sys.stderr, 'Warning: Block with key "%s" already exists.\n\tIgnoring: %s'%(key, xml_file)
 			except ParseXML.XMLSyntaxError, e: 
 				try: #try to add the xml file as a block tree
 					ParseXML.validate_dtd(xml_file, BLOCK_TREE_DTD)
diff --git a/grc/base/Port.py b/grc/base/Port.py
index 494ea894f..7a1b5d4e6 100644
--- a/grc/base/Port.py
+++ b/grc/base/Port.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -42,8 +42,8 @@ class Port(Element):
 		The port must be non-empty and type must a possible type.
 		"""
 		Element.validate(self)
-		try: assert self.get_type() in self.get_types()
-		except AssertionError: self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
+		if self.get_type() not in self.get_types():
+			self.add_error_message('Type "%s" is not a possible type.'%self.get_type())
 
 	def __str__(self):
 		if self.is_source():
diff --git a/grc/base/odict.py b/grc/base/odict.py
index ac3cb2070..044d04ad7 100644
--- a/grc/base/odict.py
+++ b/grc/base/odict.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -55,7 +55,7 @@ class odict(DictMixin):
 		@param val the value for the new entry
 		"""
 		index = (pos_key is None) and len(self._keys) or self._keys.index(pos_key)
-		assert key not in self._keys
+		if key in self._keys: raise KeyError('Cannot insert, key "%s" already exists'%str(key))
 		self._keys.insert(index+1, key)
 		self._data[key] = val
 
@@ -67,8 +67,8 @@ class odict(DictMixin):
 		@param key the key for the new entry
 		@param val the value for the new entry
 		"""
-		index = (pos_key is not None) and self._keys.index(pos_key) or 0 
-		assert key not in self._keys
+		index = (pos_key is not None) and self._keys.index(pos_key) or 0
+		if key in self._keys: raise KeyError('Cannot insert, key "%s" already exists'%str(key))
 		self._keys.insert(index, key)
 		self._data[key] = val
 
diff --git a/grc/blocks/Makefile.am b/grc/blocks/Makefile.am
index 6f7802169..81eb81182 100644
--- a/grc/blocks/Makefile.am
+++ b/grc/blocks/Makefile.am
@@ -48,6 +48,7 @@ dist_ourdata_DATA = \
 	blks2_packet_decoder.xml \
 	blks2_packet_encoder.xml \
 	blks2_pfb_arb_resampler.xml \
+	blks2_pfb_channelizer.xml \
 	blks2_qamx_demod.xml \
 	blks2_qamx_mod.xml \
 	blks2_rational_resampler_xxx.xml \
@@ -119,6 +120,7 @@ dist_ourdata_DATA = \
 	gr_head.xml \
 	gr_hilbert_fc.xml \
 	gr_iir_filter_ffd.xml \
+	gr_int_to_float.xml \
 	gr_integrate_xx.xml \
 	gr_interleave.xml \
 	gr_interleaved_short_to_complex.xml \
@@ -147,6 +149,7 @@ dist_ourdata_DATA = \
 	gr_peak_detector2_fb.xml \
 	gr_peak_detector_xb.xml \
 	gr_pfb_clock_sync.xml \
+	gr_pfb_synthesis_filterbank.xml \
 	gr_phase_modulator_fc.xml \
 	gr_pll_carriertracking_cc.xml \
 	gr_pll_freqdet_cf.xml \
diff --git a/grc/blocks/blks2_dxpsk2_demod.xml b/grc/blocks/blks2_dxpsk2_demod.xml
index ce8305c50..7fe4be32b 100644
--- a/grc/blocks/blks2_dxpsk2_demod.xml
+++ b/grc/blocks/blks2_dxpsk2_demod.xml
@@ -11,7 +11,8 @@
 	<make>blks2.$(type)2_demod(
 	samples_per_symbol=$samples_per_symbol,
 	excess_bw=$excess_bw,
-	costas_alpha=$costas_alpha,
+        freq_alpha=$freq_alpha,
+        phase_alpha=$phase_alpha,
 	timing_alpha=$timing_alpha,
 	timing_max_dev=$timing_max_dev,
 	gray_code=$gray_code,
@@ -48,9 +49,15 @@
 		<type>real</type>
 	</param>
 	<param>
-		<name>Costas Alpha</name>
-		<key>costas_alpha</key>
-		<value>0.175</value>
+		<name>FLL Alpha</name>
+		<key>freq_alpha</key>
+		<value>0.010</value>
+		<type>real</type>
+	</param>
+	<param>
+		<name>Phase Alpha</name>
+		<key>phase_alpha</key>
+		<value>0.100</value>
 		<type>real</type>
 	</param>
 	<param>
diff --git a/grc/blocks/blks2_pfb_channelizer.xml b/grc/blocks/blks2_pfb_channelizer.xml
new file mode 100644
index 000000000..aee9dd512
--- /dev/null
+++ b/grc/blocks/blks2_pfb_channelizer.xml
@@ -0,0 +1,53 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Polyphase Channelizer
+###################################################
+ -->
+<block>
+	<name>Polyphase Channelizer</name>
+	<key>blks2_pfb_channelizer_ccf</key>
+	<import>from gnuradio import blks2</import>
+	<import>from gnuradio.gr import firdes</import>
+	<make>blks2.pfb_channelizer_ccf(
+	  $nchans,
+	  $taps,
+	  $osr,
+	  $atten)
+	</make>
+	<!-- Set taps not implemented yet 
+           <callback>set_taps($taps)</callback>
+         -->
+	<param>
+		<name>Channels</name>
+		<key>nchans</key>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Taps</name>
+		<key>taps</key>
+		<value>None</value>
+		<type>real_vector</type>
+	</param>
+	<param>
+		<name>Over Sample Ratio</name>
+		<key>osr</key>
+		<value>1.0</value>
+		<type>real</type>
+	</param>
+	<param>
+		<name>Attenuation</name>
+		<key>atten</key>
+		<value>100</value>
+		<type>real</type>
+	</param>
+	<sink>
+		<name>in</name>
+		<type>complex</type>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>complex</type>
+		<nports>$nchans</nports>
+	</source>
+</block>
diff --git a/grc/blocks/block_tree.xml b/grc/blocks/block_tree.xml
index 549ffbdbf..66094a80d 100644
--- a/grc/blocks/block_tree.xml
+++ b/grc/blocks/block_tree.xml
@@ -76,6 +76,8 @@
 		<block>gr_float_to_short</block>
 		<block>gr_short_to_float</block>
 
+		<block>gr_int_to_float</block>
+
 		<block>gr_float_to_char</block>
 		<block>gr_char_to_float</block>
 
@@ -173,6 +175,8 @@
 		<block>blks2_analysis_filterbank</block>
 		<!-- Polyphase filters -->
 		<block>blks2_pfb_arb_resampler_ccf</block>
+		<block>blks2_pfb_channelizer_ccf</block>
+		<block>gr_pfb_synthesis_filterbank_ccf</block>
 		<!-- Other filters -->
 		<block>gr_single_pole_iir_filter_xx</block>
 		<block>gr_hilbert_fc</block>
diff --git a/grc/blocks/gr_int_to_float.xml b/grc/blocks/gr_int_to_float.xml
new file mode 100644
index 000000000..8e6d024e2
--- /dev/null
+++ b/grc/blocks/gr_int_to_float.xml
@@ -0,0 +1,20 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Int to Float:
+###################################################
+ -->
+<block>
+	<name>Int To Float</name>
+	<key>gr_int_to_float</key>
+	<import>from gnuradio import gr</import>
+	<make>gr.int_to_float()</make>
+	<sink>
+		<name>in</name>
+		<type>int</type>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>float</type>
+	</source>
+</block>
diff --git a/grc/blocks/gr_pfb_synthesis_filterbank.xml b/grc/blocks/gr_pfb_synthesis_filterbank.xml
new file mode 100644
index 000000000..a8b944c6a
--- /dev/null
+++ b/grc/blocks/gr_pfb_synthesis_filterbank.xml
@@ -0,0 +1,43 @@
+<?xml version="1.0"?>
+<!--
+###################################################
+##Polyphase Synthesis Filterbank
+###################################################
+ -->
+<block>
+	<name>Polyphase Synthesis Filterbank</name>
+	<key>gr_pfb_synthesis_filterbank_ccf</key>
+	<import>from gnuradio import gr</import>
+	<import>from gnuradio.gr import firdes</import>
+	<make>gr.pfb_synthesis_filterbank_ccf(
+	  $numchans, $taps)
+	</make>
+        <callback>set_taps($taps)</callback>
+
+	<param>
+		<name>Channels</name>
+		<key>numchans</key>
+		<value>2</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Connections</name>
+		<key>connections</key>
+		<value>2</value>
+		<type>int</type>
+	</param>
+	<param>
+		<name>Taps</name>
+		<key>taps</key>
+		<type>real_vector</type>
+	</param>
+	<sink>
+		<name>in</name>
+		<type>complex</type>
+		<nports>$connections</nports>
+	</sink>
+	<source>
+		<name>out</name>
+		<type>complex</type>
+	</source>
+</block>
diff --git a/grc/grc.conf.in b/grc/grc.conf.in
index 37a049971..9363ca981 100644
--- a/grc/grc.conf.in
+++ b/grc/grc.conf.in
@@ -3,7 +3,6 @@
 # ~/.gnuradio/config.conf
 
 [grc]
-pythonw = @pythonw@
 doc_dir = @docdir@
 global_blocks_path = @blocksdir@
 local_blocks_path =
diff --git a/grc/gui/ActionHandler.py b/grc/gui/ActionHandler.py
index 350b297bb..15785f2ee 100644
--- a/grc/gui/ActionHandler.py
+++ b/grc/gui/ActionHandler.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009, 2011 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -78,8 +78,7 @@ class ActionHandler:
 		When not in focus, gtk and the accelerators handle the the key press.
 		@return false to let gtk handle the key action
 		"""
-		try: assert self.get_focus_flag()
-		except AssertionError: return False
+		if not self.get_focus_flag(): return False
 		return Actions.handle_key_press(event)
 
 	def _quit(self, window, event):
diff --git a/grc/gui/Actions.py b/grc/gui/Actions.py
index f374efde1..4d196477e 100644
--- a/grc/gui/Actions.py
+++ b/grc/gui/Actions.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -76,7 +76,8 @@ class Action(gtk.Action):
 		for i in range(len(keypresses)/2):
 			keyval, mod_mask = keypresses[i*2:(i+1)*2]
 			#register this keypress
-			assert not _actions_keypress_dict.has_key((keyval, mod_mask))
+			if _actions_keypress_dict.has_key((keyval, mod_mask)):
+				raise KeyError('keyval/mod_mask pair already registered "%s"'%str((keyval, mod_mask)))
 			_actions_keypress_dict[(keyval, mod_mask)] = self
 			#set the accelerator group, and accelerator path
 			#register the key name and mod mask with the accelerator path
diff --git a/grc/gui/FlowGraph.py b/grc/gui/FlowGraph.py
index 897145a1d..9f3326ada 100644
--- a/grc/gui/FlowGraph.py
+++ b/grc/gui/FlowGraph.py
@@ -1,5 +1,5 @@
 """
-Copyright 2007, 2008, 2009, 2010 Free Software Foundation, Inc.
+Copyright 2007-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -290,10 +290,10 @@ class FlowGraph(Element):
 		for selected in selected_elements:
 			if selected in elements: continue
 			selected_elements.remove(selected)
-		try: assert self._old_selected_port.get_parent() in elements
-		except: self._old_selected_port = None
-		try: assert self._new_selected_port.get_parent() in elements
-		except: self._new_selected_port = None
+		if self._old_selected_port and self._old_selected_port.get_parent() not in elements:
+			self._old_selected_port = None
+		if self._new_selected_port and self._new_selected_port.get_parent() not in elements:
+			self._new_selected_port = None
 		#update highlighting
 		for element in elements:
 			element.set_highlighted(element in selected_elements)
diff --git a/grc/gui/Utils.py b/grc/gui/Utils.py
index b5489d56e..bb19ed3d9 100644
--- a/grc/gui/Utils.py
+++ b/grc/gui/Utils.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -53,7 +53,8 @@ def get_rotated_coordinate(coor, rotation):
 	"""
 	#handles negative angles
 	rotation = (rotation + 360)%360
-	assert rotation in POSSIBLE_ROTATIONS
+	if rotation not in POSSIBLE_ROTATIONS:
+		raise ValueError('unusable rotation angle "%s"'%str(rotation))
 	#determine the number of degrees to rotate
 	cos_r, sin_r = {
 		0: (1, 0),
diff --git a/grc/python/Block.py b/grc/python/Block.py
index bd03eb5cd..14a5859e4 100644
--- a/grc/python/Block.py
+++ b/grc/python/Block.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -65,9 +65,8 @@ class Block(_Block, _GUIBlock):
 		for check in self._checks:
 			check_res = self.resolve_dependencies(check)
 			try:
-				check_eval = self.get_parent().evaluate(check_res)
-				try: assert check_eval
-				except AssertionError: self.add_error_message('Check "%s" failed.'%check)
+				if not self.get_parent().evaluate(check_res):
+					self.add_error_message('Check "%s" failed.'%check)
 			except: self.add_error_message('Check "%s" did not evaluate.'%check)
 
 	def rewrite(self):
@@ -134,9 +133,9 @@ class Block(_Block, _GUIBlock):
 			try:
 				value = param.get_evaluated()
 				value = value + direction
-				assert 0 < value
-				param.set_value(value)
-				changed = True
+				if 0 < value:
+					param.set_value(value)
+					changed = True
 			except: pass
 		return changed
 
diff --git a/grc/python/Connection.py b/grc/python/Connection.py
index edc18841a..39f915740 100644
--- a/grc/python/Connection.py
+++ b/grc/python/Connection.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -38,5 +38,5 @@ class Connection(_Connection, _GUIConnection):
 		#check vector length
 		source_vlen = self.get_source().get_vlen()
 		sink_vlen = self.get_sink().get_vlen()
-		try: assert source_vlen == sink_vlen
-		except AssertionError: self.add_error_message('Source vector length "%s" does not match sink vector length "%s".'%(source_vlen, sink_vlen))
+		if source_vlen != sink_vlen:
+			self.add_error_message('Source vector length "%s" does not match sink vector length "%s".'%(source_vlen, sink_vlen))
diff --git a/grc/python/Constants.py b/grc/python/Constants.py
index e661c3927..868c822aa 100644
--- a/grc/python/Constants.py
+++ b/grc/python/Constants.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -23,10 +23,8 @@ from gnuradio import gr
 
 _gr_prefs = gr.prefs()
 
-PYEXEC = os.environ.get('PYTHONW', _gr_prefs.get_string('grc', 'pythonw', ''))
-
 #setup paths
-PATH_SEP = ':'
+PATH_SEP = {'/':':', '\\':';'}[os.path.sep]
 DOCS_DIR = os.environ.get('GR_DOC_DIR', _gr_prefs.get_string('grc', 'doc_dir', ''))
 HIER_BLOCKS_LIB_DIR = os.path.join(os.path.expanduser('~'), '.grc_gnuradio')
 BLOCKS_DIRS = filter( #filter blank strings
diff --git a/grc/python/FlowGraph.py b/grc/python/FlowGraph.py
index b2d406bbd..89a169355 100644
--- a/grc/python/FlowGraph.py
+++ b/grc/python/FlowGraph.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -48,15 +48,16 @@ class FlowGraph(_FlowGraph, _GUIFlowGraph):
 		#return from cache
 		return self._eval_cache[my_hash]
 
-	def _get_io_signaturev(self, pad_key):
+	def get_io_signaturev(self, direction):
 		"""
 		Get a list of io signatures for this flow graph.
-		The pad key determines the directionality of the io signature.
-		@param pad_key a string of pad_source or pad_sink
+		@param direction a string of 'in' or 'out'
 		@return a list of dicts with: type, label, vlen, size
 		"""
-		pads = filter(lambda b: b.get_key() == pad_key, self.get_enabled_blocks())
-		sorted_pads = sorted(pads, lambda x, y: cmp(x.get_id(), y.get_id()))
+		sorted_pads = {
+			'in': self.get_pad_sources(),
+			'out': self.get_pad_sinks(),
+		}[direction]
 		#load io signature
 		return [{
 			'label': str(pad.get_param('label').get_evaluated()),
@@ -65,19 +66,21 @@ class FlowGraph(_FlowGraph, _GUIFlowGraph):
 			'size': pad.get_param('type').get_opt('size'),
 		} for pad in sorted_pads]
 
-	def get_input_signaturev(self):
+	def get_pad_sources(self):
 		"""
-		Get the io signature for the input side of this flow graph.
-		@return a list of io signature structures
+		Get a list of pad source blocks sorted by id order.
+		@return a list of pad source blocks in this flow graph
 		"""
-		return self._get_io_signaturev('pad_source')
+		pads = filter(lambda b: b.get_key() == 'pad_source', self.get_enabled_blocks())
+		return sorted(pads, lambda x, y: cmp(x.get_id(), y.get_id()))
 
-	def get_output_signaturev(self):
+	def get_pad_sinks(self):
 		"""
-		Get the io signature for the output side of this flow graph.
-		@return a list of io signature structures
+		Get a list of pad sink blocks sorted by id order.
+		@return a list of pad sink blocks in this flow graph
 		"""
-		return self._get_io_signaturev('pad_sink')
+		pads = filter(lambda b: b.get_key() == 'pad_sink', self.get_enabled_blocks())
+		return sorted(pads, lambda x, y: cmp(x.get_id(), y.get_id()))
 
 	def get_imports(self):
 		"""
diff --git a/grc/python/Generator.py b/grc/python/Generator.py
index b669fa65a..b31f0a009 100644
--- a/grc/python/Generator.py
+++ b/grc/python/Generator.py
@@ -18,14 +18,14 @@ Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301, USA
 """
 
 import os
+import sys
 import subprocess
 import tempfile
 from Cheetah.Template import Template
 import expr_utils
 from Constants import \
 	TOP_BLOCK_FILE_MODE, HIER_BLOCK_FILE_MODE, \
-	HIER_BLOCKS_LIB_DIR, PYEXEC, \
-	FLOW_GRAPH_TEMPLATE
+	HIER_BLOCKS_LIB_DIR, FLOW_GRAPH_TEMPLATE
 import convert_hier
 from .. gui import Messages
 
@@ -74,10 +74,20 @@ Add a Misc->Throttle block to your flow graph to avoid CPU congestion.''')
 		Execute this python flow graph.
 		@return a popen object
 		"""
-		#execute
-		cmds = [PYEXEC, '-u', self.get_file_path()] #-u is unbuffered stdio
-		if self._generate_options == 'no_gui':
+		#extract the path to the python executable
+		python_exe = sys.executable
+
+		#when using wx gui on mac os, execute with pythonw
+		if self._generate_options == 'wx_gui' and 'darwin' in sys.platform.lower():
+			python_exe += 'w'
+
+		#setup the command args to run
+		cmds = [python_exe, '-u', self.get_file_path()] #-u is unbuffered stdio
+
+		#when in no gui mode on linux, use an xterm (looks nice)
+		if self._generate_options == 'no_gui' and 'linux' in sys.platform.lower():
 			cmds = ['xterm', '-e'] + cmds
+
 		p = subprocess.Popen(args=cmds, stdout=subprocess.PIPE, stderr=subprocess.STDOUT, shell=False, universal_newlines=True)
 		return p
 
diff --git a/grc/python/Param.py b/grc/python/Param.py
index 303ab3ed8..5536138c1 100644
--- a/grc/python/Param.py
+++ b/grc/python/Param.py
@@ -213,8 +213,7 @@ class Param(_Param, _GUIParam):
 			lambda p: p._vlen, self.get_parent().get_ports())
 		):
 			try:
-				assert int(self.get_evaluated()) == 1
-				return 'part'
+				if int(self.get_evaluated()) == 1: return 'part'
 			except: pass
 		#hide empty grid positions
 		if self.get_key() in ('grid_pos', 'notebook') and not self.get_value(): return 'part'
@@ -244,8 +243,7 @@ class Param(_Param, _GUIParam):
 		def eval_string(v):
 			try:
 				e = self.get_parent().get_parent().evaluate(v)
-				assert isinstance(e, str)
-				return e
+				if isinstance(e, str): return e
 			except:
 				self._stringify_flag = True
 				return v
@@ -265,21 +263,21 @@ class Param(_Param, _GUIParam):
 			#raise an exception if the data is invalid
 			if t == 'raw': return e
 			elif t == 'complex':
-				try: assert isinstance(e, COMPLEX_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type complex.'%str(e)
+				if not isinstance(e, COMPLEX_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type complex.'%str(e)
 				return e
 			elif t == 'real':
-				try: assert isinstance(e, REAL_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type real.'%str(e)
+				if not isinstance(e, REAL_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type real.'%str(e)
 				return e
 			elif t == 'int':
-				try: assert isinstance(e, INT_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type integer.'%str(e)
+				if not isinstance(e, INT_TYPES):
+					raise Exception, 'Expression "%s" is invalid for type integer.'%str(e)
 				return e
 			elif t == 'hex': return hex(e)
 			elif t == 'bool':
-				try: assert isinstance(e, bool)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type bool.'%str(e)
+				if not isinstance(e, bool):
+					raise Exception, 'Expression "%s" is invalid for type bool.'%str(e)
 				return e
 			else: raise TypeError, 'Type "%s" not handled'%t
 		#########################
@@ -295,25 +293,22 @@ class Param(_Param, _GUIParam):
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, COMPLEX_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type complex vector.'%str(e)
+				if not all([isinstance(ei, COMPLEX_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type complex vector.'%str(e)
 				return e
 			elif t == 'real_vector':
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, REAL_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type real vector.'%str(e)
+				if not all([isinstance(ei, REAL_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type real vector.'%str(e)
 				return e
 			elif t == 'int_vector':
 				if not isinstance(e, VECTOR_TYPES):
 					self._lisitify_flag = True
 					e = [e]
-				try:
-					for ei in e: assert isinstance(ei, INT_TYPES)
-				except AssertionError: raise Exception, 'Expression "%s" is invalid for type integer vector.'%str(e)
+				if not all([isinstance(ei, INT_TYPES) for ei in e]):
+					raise Exception, 'Expression "%s" is invalid for type integer vector.'%str(e)
 				return e
 		#########################
 		# String Types
@@ -327,13 +322,13 @@ class Param(_Param, _GUIParam):
 		#########################
 		elif t == 'id':
 			#can python use this as a variable?
-			try: assert _check_id_matcher.match(v)
-			except AssertionError: raise Exception, 'ID "%s" must begin with a letter and may contain letters, numbers, and underscores.'%v
+			if not _check_id_matcher.match(v):
+				raise Exception, 'ID "%s" must begin with a letter and may contain letters, numbers, and underscores.'%v
 			ids = [param.get_value() for param in self.get_all_params(t)]
-			try: assert ids.count(v) <= 1 #id should only appear once, or zero times if block is disabled
-			except: raise Exception, 'ID "%s" is not unique.'%v
-			try: assert v not in ID_BLACKLIST
-			except: raise Exception, 'ID "%s" is blacklisted.'%v
+			if ids.count(v) > 1: #id should only appear once, or zero times if block is disabled
+				raise Exception, 'ID "%s" is not unique.'%v
+			if v in ID_BLACKLIST:
+				raise Exception, 'ID "%s" is blacklisted.'%v
 			return v
 		#########################
 		# Stream ID Type
@@ -346,12 +341,12 @@ class Param(_Param, _GUIParam):
 			)]
 			#check that the virtual sink's stream id is unique
 			if self.get_parent().is_virtual_sink():
-				try: assert ids.count(v) <= 1 #id should only appear once, or zero times if block is disabled
-				except: raise Exception, 'Stream ID "%s" is not unique.'%v
+				if ids.count(v) > 1: #id should only appear once, or zero times if block is disabled
+					raise Exception, 'Stream ID "%s" is not unique.'%v
 			#check that the virtual source's steam id is found
 			if self.get_parent().is_virtual_source():
-				try: assert v in ids
-				except: raise Exception, 'Stream ID "%s" is not found.'%v
+				if v not in ids:
+					raise Exception, 'Stream ID "%s" is not found.'%v
 			return v
 		#########################
 		# GUI Position/Hint
@@ -382,17 +377,15 @@ class Param(_Param, _GUIParam):
 		elif t == 'grid_pos':
 			if not v: return '' #allow for empty grid pos
 			e = self.get_parent().get_parent().evaluate(v)
-			try:
-				assert isinstance(e, (list, tuple)) and len(e) == 4
-				for ei in e: assert isinstance(ei, int)
-			except AssertionError: raise Exception, 'A grid position must be a list of 4 integers.'
+			if not isinstance(e, (list, tuple)) or len(e) != 4 or not all([isinstance(ei, int) for ei in e]):
+				raise Exception, 'A grid position must be a list of 4 integers.'
 			row, col, row_span, col_span = e
 			#check row, col
-			try: assert row >= 0 and col >= 0
-			except AssertionError: raise Exception, 'Row and column must be non-negative.'
+			if row < 0 or col < 0:
+				raise Exception, 'Row and column must be non-negative.'
 			#check row span, col span
-			try: assert row_span > 0 and col_span > 0
-			except AssertionError: raise Exception, 'Row and column span must be greater than zero.'
+			if row_span <= 0 or col_span <= 0:
+				raise Exception, 'Row and column span must be greater than zero.'
 			#get hostage cell parent
 			try: my_parent = self.get_parent().get_param('notebook').evaluate()
 			except: my_parent = ''
@@ -421,8 +414,8 @@ class Param(_Param, _GUIParam):
 			try: notebook_block = filter(lambda b: b.get_id() == notebook_id, notebook_blocks)[0]
 			except: raise Exception, 'Notebook id "%s" is not an existing notebook id.'%notebook_id
 			#check that page index exists
-			try: assert int(page_index) in range(len(notebook_block.get_param('labels').evaluate()))
-			except: raise Exception, 'Page index "%s" is not a valid index number.'%page_index
+			if int(page_index) not in range(len(notebook_block.get_param('labels').evaluate())):
+				raise Exception, 'Page index "%s" is not a valid index number.'%page_index
 			return notebook_id, page_index
 		#########################
 		# Import Type
diff --git a/grc/python/Platform.py b/grc/python/Platform.py
index ec3f94096..a9c2b18ad 100644
--- a/grc/python/Platform.py
+++ b/grc/python/Platform.py
@@ -1,5 +1,5 @@
-"""
-Copyright 2008, 2009, 2010, 2011 Free Software Foundation, Inc.
+__doc__ = """
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
diff --git a/grc/python/Port.py b/grc/python/Port.py
index 6e5a5c59f..3846b0f4e 100644
--- a/grc/python/Port.py
+++ b/grc/python/Port.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -83,16 +83,16 @@ class Port(_Port, _GUIPort):
 
 	def validate(self):
 		_Port.validate(self)
-		try: assert self.get_enabled_connections() or self.get_optional()
-		except AssertionError: self.add_error_message('Port is not connected.')
-		try: assert self.is_source() or len(self.get_enabled_connections()) <= 1
-		except AssertionError: self.add_error_message('Port has too many connections.')
+		if not self.get_enabled_connections() and not self.get_optional():
+			self.add_error_message('Port is not connected.')
+		if not self.is_source() and len(self.get_enabled_connections()) > 1:
+			self.add_error_message('Port has too many connections.')
 		#message port logic
 		if self.get_type() == 'msg':
-			try: assert not self.get_nports()
-			except AssertionError: self.add_error_message('A port of type "msg" cannot have "nports" set.')
-			try: assert self.get_vlen() == 1
-			except AssertionError: self.add_error_message('A port of type "msg" must have a "vlen" of 1.')
+			if self.get_nports():
+				self.add_error_message('A port of type "msg" cannot have "nports" set.')
+			if self.get_vlen() != 1:
+				self.add_error_message('A port of type "msg" must have a "vlen" of 1.')
 
 	def rewrite(self):
 		"""
@@ -134,8 +134,7 @@ class Port(_Port, _GUIPort):
 		if not nports: return ''
 		try:
 			nports = int(self.get_parent().get_parent().evaluate(nports))
-			assert 0 < nports
-			return nports
+			if 0 < nports: return nports
 		except: return 1
 
 	def get_optional(self): return bool(self._optional)
diff --git a/grc/python/convert_hier.py b/grc/python/convert_hier.py
index befddccea..c6ca5b769 100644
--- a/grc/python/convert_hier.py
+++ b/grc/python/convert_hier.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -23,11 +23,11 @@ from .. base import odict
 
 def convert_hier(flow_graph, python_file):
 	#extract info from the flow graph
-	input_sigs = flow_graph.get_input_signaturev()
-	output_sigs = flow_graph.get_output_signaturev()
+	input_sigs = flow_graph.get_io_signaturev('in')
+	output_sigs = flow_graph.get_io_signaturev('out')
 	parameters = flow_graph.get_parameters()
 	block_key = flow_graph.get_option('id')
-	block_name = flow_graph.get_option('title')
+	block_name = flow_graph.get_option('title') or flow_graph.get_option('id').replace('_', ' ').title()
 	block_category = flow_graph.get_option('category')
 	block_desc = flow_graph.get_option('description')
 	block_author = flow_graph.get_option('author')
@@ -56,19 +56,21 @@ def convert_hier(flow_graph, python_file):
 		params_n.append(param_n)
 	block_n['param'] = params_n
 	#sink data
+	block_n['sink'] = list()
 	for input_sig in input_sigs:
 		sink_n = odict()
 		sink_n['name'] = input_sig['label']
 		sink_n['type'] = input_sig['type']
 		sink_n['vlen'] = input_sig['vlen']
-		block_n['sink'] = sink_n
+		block_n['sink'].append(sink_n)
 	#source data
+	block_n['source'] = list()
 	for output_sig in output_sigs:
 		source_n = odict()
 		source_n['name'] = output_sig['label']
 		source_n['type'] = output_sig['type']
 		source_n['vlen'] = output_sig['vlen']
-		block_n['source'] = source_n
+		block_n['source'].append(source_n)
 	#doc data
 	block_n['doc'] = "%s\n%s\n%s"%(block_author, block_desc, python_file)
 	#write the block_n to file
diff --git a/grc/python/expr_utils.py b/grc/python/expr_utils.py
index 3c39f5d89..a2e56eedf 100644
--- a/grc/python/expr_utils.py
+++ b/grc/python/expr_utils.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -118,7 +118,7 @@ def sort_variables(exprs):
 	Get a list of variables in order of dependencies.
 	@param exprs a mapping of variable name to expression
 	@return a list of variable names
-	@throws AssertionError circular dependencies
+	@throws Exception circular dependencies
 	"""
 	var_graph = get_graph(exprs)
 	sorted_vars = list()
@@ -126,7 +126,7 @@ def sort_variables(exprs):
 	while var_graph.get_nodes():
 		#get a list of nodes with no edges
 		indep_vars = filter(lambda var: not var_graph.get_edges(var), var_graph.get_nodes())
-		assert indep_vars
+		if not indep_vars: raise Exception('circular dependency caught in sort_variables')
 		#add the indep vars to the end of the list
 		sorted_vars.extend(sorted(indep_vars))
 		#remove each edge-less node from the graph
diff --git a/grc/python/extract_docs.py b/grc/python/extract_docs.py
index f41f415b2..aa85397f9 100644
--- a/grc/python/extract_docs.py
+++ b/grc/python/extract_docs.py
@@ -1,5 +1,5 @@
 """
-Copyright 2008, 2009 Free Software Foundation, Inc.
+Copyright 2008-2011 Free Software Foundation, Inc.
 This file is part of GNU Radio
 
 GNU Radio Companion is free software; you can redistribute it and/or
@@ -81,8 +81,8 @@ def extract(key):
 	@param key the block key
 	@return a string with documentation
 	"""
-	try: assert _docs_cache.has_key(key)
-	except: _docs_cache[key] = _extract(key)
+	if not _docs_cache.has_key(key):
+		_docs_cache[key] = _extract(key)
 	return _docs_cache[key]
 
 if __name__ == '__main__':
diff --git a/grc/python/flow_graph.tmpl b/grc/python/flow_graph.tmpl
index e16e86f5b..d5e53b52b 100644
--- a/grc/python/flow_graph.tmpl
+++ b/grc/python/flow_graph.tmpl
@@ -74,8 +74,8 @@ class $(class_name)(gr.top_block):
 	def __init__($param_str):
 		gr.top_block.__init__(self, "$title")
 #elif $generate_options == 'hb'
-	#set $in_sigs = $flow_graph.get_input_signaturev()
-	#set $out_sigs = $flow_graph.get_output_signaturev()
+	#set $in_sigs = $flow_graph.get_io_signaturev('in')
+	#set $out_sigs = $flow_graph.get_io_signaturev('out')
 class $(class_name)(gr.hier_block2):
 #def make_io_sig($io_sigs)
 	#set $size_strs = ['%s*%s'%(io_sig['size'], io_sig['vlen']) for io_sig in $io_sigs]
@@ -153,11 +153,13 @@ gr.io_signaturev($(len($io_sigs)), $(len($io_sigs)), [$(', '.join($size_strs))])
 ##	The port name should be the id of the parent block.
 ##	However, port names for IO pads should be self.
 ########################################################
-#def make_port_name($port)
-	#if $port.get_parent().get_key().startswith('pad_')
-self#slurp
+#def make_port_sig($port)
+	#if $port.get_parent().get_key() == 'pad_source'
+(self, $flow_graph.get_pad_sources().index($port.get_parent()))#slurp
+	#elif $port.get_parent().get_key() == 'pad_sink'
+(self, $flow_graph.get_pad_sinks().index($port.get_parent()))#slurp
 	#else
-self.$port.get_parent().get_id()#slurp
+(self.$port.get_parent().get_id(), $port.get_key())#slurp
 	#end if
 #end def
 #if $connections
@@ -175,7 +177,7 @@ self.$port.get_parent().get_id()#slurp
 	#end if
 	##do not generate connections with virtual sinks
 	#if not $sink.get_parent().is_virtual_sink()
-		self.connect(($make_port_name($source), $source.get_key()), ($make_port_name($sink), $sink.get_key()))
+		self.connect($make_port_sig($source), $make_port_sig($sink))
 	#end if
 #end for
 
@@ -242,6 +244,7 @@ if __name__ == '__main__':
 	#end if
 	tb.show()
 	qapp.exec_()
+	tb.stop()
 	#elif $generate_options == 'no_gui'
 	tb = $(class_name)($(', '.join($params_eq_list)))
 		#set $run_options = $flow_graph.get_option('run_options')