for testing something I am trying to develop my own SineWave generator using python block in gnuradio
the block is here
"""
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
from gnuradio import gr
class blk(gr.sync_block): # other base classes are basic_block, decim_block, interp_block
"""Embedded Python Block example - a simple multiply const"""
def __init__(self, sample_rate=192e3, frequency=1e3, amplitude=1): # only default arguments here
"""arguments to this function show up as parameters in GRC"""
gr.sync_block.__init__(
self,
name='SineWave Generator', # will show up in GRC
in_sig=[np.float32],
#in_sig=None,
out_sig=[np.float32]
)
# if an attribute with the same name as a parameter is found,
# a callback is registered (properties work, too).
self.sample_rate = sample_rate
self.frequency = frequency
self.amplitude = amplitude
def work(self, input_items, output_items):
"""example: multiply with constant"""
print "length of input =", len(input_items[0])
print "length of output =", len(output_items[0])
for i in range(0, len(output_items[0])): #8192
output_items[0][i] = np.sin(2 * np.pi * self.frequency * (i / self.sample_rate)) * self.amplitude
return len(output_items[0])
and is used in my flowgraph like so https://imgur.com/28kE1Sj
this block produces sine wave corecly but the audio is realy choopy like I woulldn't be able to generate sinewave fast enough or something (sample_rate shouldn't be a problem as the same flowgraph works corecly if I substitute my block with Signal Source)
also I am using Null source (because I didn't yet figure out how to create a python block without any source (as soon as I set in_sig=None no audio ever comes out of my block, so I am not sure how Signal source gets away with generating audio without any source connected to its input)
Thanks for Anwsering and Best Regards