I
am trying to implement this discussion:[Discuss-gnuradio] Change
frequency in USRP
source automatically
(https://lists.gnu.org/archive/html/discuss-gnuradio/2016-03/msg00402.html).
My objective is to create a block which changes the frequency
automatically in steps of 2e6, starting from 2.37e9.
My block has a code given below:
import string
import numpy
import pmt
from gnuradio import gr
from gnuradio import digital
class frew_sweep_v1_f(gr.sync_block):
"""
docstring for block frew_sweep_v1_f
"""
def __init__(self,initial_freq=2.37e9, step=2e6):
gr.sync_block.__init__(self,
name="frew_sweep_v1_f",
in_sig=[],
out_sig=[])
self.message_port_register_in(pmt.intern('clock'))
self.message_port_register_out(pmt.intern('sync'))
self.set_msg_handler(pmt.intern('clock'),self.handler)
self.freq=initial_freq
self.step=step
def handler(self,pdu):
self.message_port_pub(pmt.intern('sync'),pmt.cons(pmt.intern("freq"),pmt.to_pmt(self.freq)))
self.freq+=self.step
the xml file has a code given below:
<block>
<name>frew_sweep_v1_f</name>
<key>tutorial_frew_sweep_v1_f</key>
<category>[tutorial]</category>
<import>import tutorial</import>
<import>from gnuradio.digital import packet_utils</import>
<make>tutorial.frew_sweep_v1_f($initial_freq, $step)</make>
<callback>post_message($msg)</callback>
<param>
<name>message</name>
<key>msg</key>
<type>string</type>
</param>
<sink>
<name>in</name>
<type>message</type>
</sink>
<source>
<name>out</name>
<type>message</type>
</source>
</block>
I inserted this new block between a message block and message debug block.
The new top_block code generated is given below:
if __name__ == '__main__':
import ctypes
import sys
if sys.platform.startswith('linux'):
try:
x11 = ctypes.cdll.LoadLibrary('libX11.so')
x11.XInitThreads()
except:
print "Warning: failed to XInitThreads()"
from PyQt4 import Qt
from gnuradio import digital
from gnuradio import blocks
from gnuradio import eng_notation
from gnuradio import gr
from gnuradio.digital import packet_utils
from gnuradio.eng_option import eng_option
from gnuradio.filter import firdes
from optparse import OptionParser
import pmt
import sys
import tutorial
from gnuradio import qtgui
class top_blockRSM_frew_sweepv1(gr.top_block, Qt.QWidget):
def __init__(self):
gr.top_block.__init__(self, "Top Blockrsm Frew Sweepv1")
Qt.QWidget.__init__(self)
self.setWindowTitle("Top Blockrsm Frew Sweepv1")
qtgui.util.check_set_qss()
try:
self.setWindowIcon(Qt.QIcon.fromTheme('gnuradio-grc'))
except:
pass
self.top_scroll_layout = Qt.QVBoxLayout()
self.setLayout(self.top_scroll_layout)
self.top_scroll = Qt.QScrollArea()
self.top_scroll.setFrameStyle(Qt.QFrame.NoFrame)
self.top_scroll_layout.addWidget(self.top_scroll)
self.top_scroll.setWidgetResizable(True)
self.top_widget = Qt.QWidget()
self.top_scroll.setWidget(self.top_widget)
self.top_layout = Qt.QVBoxLayout(self.top_widget)
self.top_grid_layout = Qt.QGridLayout()
self.top_layout.addLayout(self.top_grid_layout)
self.settings = Qt.QSettings("GNU Radio", "top_blockRSM_frew_sweepv1")
self.restoreGeometry(self.settings.value("geometry").toByteArray())
##################################################
# Variables
##################################################
self.samp_rate = samp_rate = 32000
##################################################
# Blocks
##################################################
self.tutorial_frew_sweep_v1_f_0 = Template error: tutorial.frew_sweep_v1_f($initial_freq, $step)
cannot find 'initial_freq'
self.blocks_message_strobe_0 = blocks.message_strobe(pmt.intern("freq"), 10000)
self.blocks_message_debug_0 = blocks.message_debug()
##################################################
# Connections
##################################################
self.msg_connect((self.blocks_message_strobe_0, 'strobe'), (self.tutorial_frew_sweep_v1_f_0, 'in'))
self.msg_connect((self.tutorial_frew_sweep_v1_f_0, 'out'), (self.blocks_message_debug_0, 'print'))
def closeEvent(self, event):
self.settings = Qt.QSettings("GNU Radio", "top_blockRSM_frew_sweepv1")
self.settings.setValue("geometry", self.saveGeometry())
event.accept()
def get_samp_rate(self):
return self.samp_rate
def set_samp_rate(self, samp_rate):
self.samp_rate = samp_rate
def main(top_block_cls=top_blockRSM_frew_sweepv1, options=None):
from distutils.version import StrictVersion
if StrictVersion(Qt.qVersion()) >= StrictVersion("4.5.0"):
style = gr.prefs().get_string('qtgui', 'style', 'raster')
Qt.QApplication.setGraphicsSystem(style)
qapp = Qt.QApplication(sys.argv)
tb = top_block_cls()
tb.start()
tb.show()
def quitting():
tb.stop()
tb.wait()
qapp.connect(qapp, Qt.SIGNAL("aboutToQuit()"), quitting)
qapp.exec_()
if __name__ == '__main__':
main()
in the code, under Blocks, it shows
self.tutorial_frew_sweep_v1_f_0 = Template error: tutorial.frew_sweep_v1_f($initial_freq, $step) cannot find 'initial_freq'
So when I Execute the flowgraph, the error pops up.
Executing: /usr/bin/python2 -u /home/pglab1/top_blockRSM_frew_sweepv3.py
File "/home/pglab1/top_blockRSM_frew_sweepv3.py", line 67
self.tutorial_frew_sweep_v1_f_0 = Template error: tutorial.frew_sweep_v1_f($initial_freq, $step)
^
SyntaxError: invalid syntax
>>> Done (return code 1)
Can someone tell why this error is created in the python code?
Thanking you
Rensi