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xfer_tracer working

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hackens-bot 2024-12-17 21:49:00 +01:00
parent 8d3f1564f4
commit 4ebd626409
2 changed files with 31 additions and 40 deletions
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24
xfer_tracer/flattop.py
View file

@ -1,24 +0,0 @@
#!/usr/bin/env python3
import numpy as np
from scipy import signal
from scipy.fft import fft, fftshift
import matplotlib.pyplot as plt
window = signal.windows.flattop(2500)
plt.plot(window)
plt.title("Flat top window")
plt.ylabel("Amplitude")
plt.xlabel("Sample")
plt.figure()
A = fft(window,65536) / (len(window)/2.0)
freq = np.linspace(-0.5*2500, 0.5*2500, len(A))
response = 20 * np.log10(np.abs(fftshift(A / abs(A).max())))
plt.plot(freq, response)
#plt.axis([-0.5, 0.5, -120, 0])
plt.title("Frequency response of the flat top window")
plt.ylabel("Normalized magnitude [dB]")
plt.xlabel("Normalized frequency [cycles per window]")
plt.show()

47
xfer_tracer/script.py
View file

@ -6,7 +6,7 @@ import time
import pyaudio as pa
import numpy as np
import scipy as sc
import matplotlib.pyplot as plt
current_phase = 0.0
normalized_f = 0.0 # in cycles per sample : f = normalized_f * f_sampling
@ -71,11 +71,13 @@ paudio = pa.PyAudio()
audio_strm = paudio.open(format=pa.paFloat32,
channels=1,
rate=48000,
rate=44100,
output=True,
input=False,
stream_callback=audio_callback,
start=True)
print(paudio.get_default_output_device_info())
print(audio_strm.is_active())
def acquire_samples(sc_frequency, oscillo):
global new_f
@ -89,16 +91,15 @@ def acquire_samples(sc_frequency, oscillo):
oscillo.write("acquire:state run")
oscillo.write("data:source CH1")
input_ch = oscillo.query_binary("curve?", container=np.array)
input_ch = oscillo.query_binary_values("curve?",datatype="b",container=np.array).astype(np.float64)
oscillo.write("data:source CH2")
output_ch = oscillo.query_binary("curve?", container=np.array)
output_ch = oscillo.query_binary_values("curve?",datatype="b",container=np.array).astype(np.float64)
return input_ch, output_ch
#return (input_ch, output_ch)
def manage_measures(f_list, oscillo): # These are NOT normalized frequencies
hscales = [25e-3, 10e-3, 5e-3, 2.5e-3, 1e-3,
500e-6, 250e-6, 100e-6, 50e-6, 25e-6, 10e-6]
hscales = [0.25, 100e-3, 50e-3, 25e-3, 10e-3, 5e-3, 2.5e-3, 1e-3, 500e-6, 250e-6, 100e-6, 50e-6, 25e-6, 10e-6]
hscales_str = ["2.5e-1", "1.0e-1", "5.0e-2", "2.5e-2", "1.0e-2", "5.0e-3", "2.5e-3", "1.0e-3", "5.0e-4", "2.5e-4", "1.0e-4", "5.0e-5", "2.5e-5", "1.0e-5"]
hscale_index = 0
current_hscale = hscales[hscale_index]
@ -112,13 +113,14 @@ def manage_measures(f_list, oscillo): # These are NOT normalized frequencies
W = sc.signal.windows.flattop(2500)
for f in f_list:
sc_frequency = np.round(2**20/48000 * f)/2**20
sc_frequency = np.round(2**20/44100 * f)/2**20
num_periods = f * 10 * current_hscale
while(num_periods >= 5 * 2.5):
hscale_index += 1
current_hscale = hscales[hscale_index]
num_periods = f * 10 * current_hscale
oscillo.write("horizontal:main:scale " + str(hscales))
print("horizontal:main:scale " + hscales_str[hscale_index])
oscillo.write("horizontal:main:scale " + hscales_str[hscale_index])
cal_done = False
print(f, " : ", current_hscale,"s/div, ", num_periods, " periods")
@ -126,14 +128,15 @@ def manage_measures(f_list, oscillo): # These are NOT normalized frequencies
if not cal_done:
cal_A, cal_B = acquire_samples(0., oscillo)
cal_done = True
print(A)
print(B)
A, B = (A - cal_A)*W, (B - cal_B)*W
f_acq = 250./current_hscale
rel_f = f / f_acq
# Obtain the Fourier transforms of A, B @ rel_f, with flattop windowing
V = np.exp(-2.0j * np.pi * np.arange(2500) * rel_f)
h = np.sum(B*V)/np.sum(A.V)
h = np.sum(B*V)/np.sum(A*V)
print("H(", f, ") = ", h)
H.append(h)
return H
@ -147,18 +150,20 @@ def find_oscillo():
# exit(1)
return rm.open_resource(R[0])
osci = find_oscillo()
osci.timeout = 10000
print(osci.query("*IDN?"))
osci.write("*RST")
time.sleep(5)
time.sleep(10)
osci.write("ch1:scale 1.0e-1")
osci.write("ch1:scale 2.5e-1")
osci.write("ch1:bandwidth ON")
osci.write("ch1:coupling AC")
osci.write("select:ch1 1")
osci.write("ch2:scale 5.0e-2")
osci.write("ch2:scale 2.5e-1")
osci.write("ch2:bandwidth ON")
osci.write("ch2:coupling AC")
osci.write("select:ch2 1")
@ -170,6 +175,16 @@ osci.write("trigger:main:type EDGE")
osci.write("acquire:mode sample")
osci.write("acquire:stopafter sequence")
osci.write("data:encdg ascii")
manage_measures([330., 470., 680., 820., 1000.])
osci.write("data:encdg RIBinary")
decade = [1.0, 1.2, 1.5, 1.8, 2.2, 2.7, 3.3, 3.9, 4.7, 5.6, 6.8, 8.2]
X = [68., 82] + list(np.array(decade)*([100.]*len(decade))) + list(np.array(decade) * ([1000.]*len(decade))) + [1e4, 1.2e4, 1.5e4, 1.8e4]
H = manage_measures(X, osci)
Y = 20 * np.log10(np.abs(H))
fig, axes = plt.subplots(nrows = 2, ncols=1, sharex = True)
axes[0].semilogx(X,Y)
axes[0].grid()
axes[1].semilogx(X, np.angle(H, deg=True))
axes[1].grid()
plt.show()