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# https://docs.cocotb.org/en/stable/quickstart.html
# test_my_design.py (extended)
import cocotb
from cocotb.triggers import FallingEdge, RisingEdge, Timer, with_timeout
from cocotb.clock import Clock
from cocotb.binary import BinaryValue
import numpy
from pcm2pdm import convert
from testsignal import generate_test_tone
from test_pdm import plot_reconstruct
sr = 16000
decimation = 64
async def drive_waveform(dut, waveform):
for a_val in waveform:
dut.pdm_in.value = bool(a_val)
await RisingEdge(dut.clk)
async def collect_output(dut, samples):
out = numpy.zeros(samples, dtype=numpy.int16)
# wait for the PCM output
for i in range(samples):
await with_timeout(RisingEdge(dut.pcm_valid), 100000, 'ns')
#dut._log.info("PCM is %s", dut.pcm_out.value)
s = dut.pcm_out.value.signed_integer
out[i] = s
return out
async def process_pdm(dut, pdm_data, decimation):
cocotb.start_soon(Clock(dut.clk, 10, units="ns").start())
cocotb.start_soon(drive_waveform(dut, pdm_data))
pcm_samples = len(pdm_data)//decimation
out = await collect_output(dut, pcm_samples)
return out
@cocotb.test()
async def test_decode_sine_1000hz(dut):
"""Try running with PDM input"""
sig = generate_test_tone(duration_sec=0.004,
freqs=[1000.0], noise_level=0.0, sample_rate=sr, amplitude=0.9,
)
pdm_data = convert(sig)
output = await process_pdm(dut, pdm_data, decimation)
output = output / 1024
fig = plot_reconstruct(sig, pdm_data, output, sr=sr, aspect=6.0)
fig.savefig('pdm_cocotb_1khz.png')
@cocotb.test()
async def test_decode_sine_200hz(dut):
"""Try running with PDM input"""
sig = generate_test_tone(duration_sec=0.008,
freqs=[200.0], noise_level=0.0, sample_rate=sr, amplitude=0.9,
)
pdm_data = convert(sig)
output = await process_pdm(dut, pdm_data, decimation)
output = output / 1024
fig = plot_reconstruct(sig, pdm_data, output, sr=sr, aspect=6.0)
fig.savefig('pdm_cocotb_200hz.png')
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