epy_block_0.py

"""
Embedded Python Blocks:

Each time this file is saved, GRC will instantiate the first class it finds
to get ports and parameters of your block. The arguments to __init__  will
be the parameters. All of them are required to have default values!
"""

import numpy as np
import pylab
from gnuradio import gr
import pmt


class msg_block(gr.basic_block):  # other base classes are basic_block, decim_block, interp_block
    """This block converts strings from the QT GUI Message Edit Box to uint8 vectors"""

    def __init__(self):  # only default arguments here
        """arguments to this function show up as parameters in GRC"""
        gr.basic_block.__init__(
            self,
            name='Embedded Python Block',   # will show up in GRC
            in_sig=None,
            out_sig=None
        )
        self.message_port_register_out(pmt.intern('msg_out'))
        self.message_port_register_in(pmt.intern('msg_in'))
        self.set_msg_handler(pmt.intern('msg_in'), self.handle_msg)
    
    def handle_msg(self, msg):
        nvec = pmt.to_python(msg)
        self.message_port_pub(pmt.intern('msg_out'), pmt.cons(pmt.make_dict(), pmt.pmt_to_python.numpy_to_uvector(np.array([ord(c) for c in nvec], np.uint8))))
    
    def work(self, input_items, output_items):
        pass