Ejemplo n.º 1
0
def period(vector, time=[], ts=-1, mode=slab.tmodeRise):
    m = slab.halfRange(vector)
    tlist = tcross(vector, m, mode, time, ts)
    n = len(tlist)
    if n < 2:
        raise slab.SlabEx("Not enough edges for period")
    sum = 0
    for i in range(0, n - 1):
        sum = sum + tlist[i + 1] - tlist[i]
    return sum / (n - 1)
Ejemplo n.º 2
0
def logRange(start, end=0, ndec=0, ppd=10):
    # Check if SciPy is loaded
    slab.checkSciPy()

    stlog = np.log10(start)
    # We don't provide end
    if end == 0:
        if ndec == 0:
            raise slab.SlabEx('Need to provide end or decades')
        return 10**np.arange(stlog, stlog + ndec, 1.0 / ppd)
    # We provide end
    endlog = np.log10(end)
    return 10**np.arange(stlog, endlog, 1.0 / ppd)
Ejemplo n.º 3
0
def distortion(v1, v2, freq, show=True):
    points = int(slab.maxSFfresponse / freq)
    if points > 100:
        points = 100
    if points < 50:
        raise slab.SlabEx("Frequency too high")

    cycles = 10
    slab.waveCosine(v1, v2, points)
    slab.setWaveFrequency(freq)
    slab.tranStore(cycles * points)
    t, s = slab.singleWaveResponse()
    if show:
        slab.plot11(t, s, "Time plot", "time(s)", "ADC1(V)")
    c, f = ftransform(s, t)
    if show:
        ac.plotFreq(f, c)

    # THD
    base = np.abs(c[cycles])
    tot = 0
    for i in range(2, 7):
        tot = tot + np.abs(c[i * cycles]) * np.abs(c[i * cycles])
    tot = np.sqrt(tot)
    print("tot: " + str(tot))
    thd = 100.0 * tot / base

    # THD+N
    rms_total = std(s)
    rms_signal = base / np.sqrt(2.0)
    rms_no_signal = np.sqrt(rms_total * rms_total - rms_signal * rms_signal)
    thdn = 100.0 * rms_no_signal / rms_signal

    # Harmonic Distortion 2nd
    h2 = dB(np.abs(c[2 * cycles]) / base)

    # Harmonic Distortion 3rd
    h3 = dB(np.abs(c[3 * cycles]) / base)

    if show:
        print()
        print("THD   : " + str(thd) + " %")
        print("THD+N : " + str(thdn) + " %")
        print("Harmonic distortion 2nd : " + str(h2) + " dBc")
        print("Harmonic distortion 3rd : " + str(h3) + " dBc")
        print()

    return thd, thdn, h2, h3
Ejemplo n.º 4
0
print()

'''
Commands without connection to the board
'''

print("Test of commands that don't require the board to be connected")
print()

# Commands: save, load
print('Checking file commands')
data1=[1,2,3]
slab.save('slabTest.dat',data1)
data2=slab.load('slabTest.dat')
if data1 != data2:
    raise slab.SlabEx("Read data don't match saved data")
print('pass')
print()

# Commands: highPeak, lowPeak, peak2peak, halfRange, mean, rms, std
data1=np.arange(0,6,0.01)
data2=0.5+np.sin(data1)
data3=np.arange(0,3,0.01)
data4=0.2+np.cos(data3)
print('Vector utility commands')
if not compare(slab.highPeak(data2),1.5):
    raise slab.SlabEx("highPeak fails")
print('  highPeak pass')
if not compare(slab.lowPeak(data2),-0.5):
    raise slab.SlabEx("lowPeak fails")
print('  lowPeak pass')
Ejemplo n.º 5
0
def sineGainAll(v1, v2, freq, npre=5, maxfs=-1):
    #global adc_delay

    # Check if SciPy is loaded
    slab.checkSciPy()

    # No sat warning yet
    satWarn = False

    # Load defaults
    if maxfs == -1:
        maxfs = slab.maxSFfresponse
    # Checks
    if not slab.opened:
        raise slab.SlabEx("Not connected to board")
    if v1 > v2:
        raise slab.SlabEx("Minimum value must be below maximum value")
    if maxfs > 1 / slab.min_sample:
        raise slab.SlabEx("Too high max sample frequency")
    if freq > maxfs / 4.0:
        raise slab.SlabEx("Frequency too high")

    # This command is silent
    prev_verbose = slab.setVerbose(0)

    # Create wave
    if maxfs > 200 * freq:
        npoints = 200
        nsamples = 200
    else:
        npoints = int(maxfs / freq)
        nsamples = int(200 / npoints) * npoints
        npre = int(npre * npoints / nsamples)

    # Create test wave
    amplitude = (v2 - v1) / 2.0
    slab.waveSine(v1, v2, npoints)
    st = slab.setWaveFrequency(freq)

    # Setup measurement
    slab.setTransientStorage(nsamples, 1)

    # Measure all channels
    list = []
    for channel in range(1, nadcs + 1):
        time, out = slab.singleWaveResponse(channel, npre, tinit=0.0)

        # Check peak values
        vmax = slab.highPeak(out)
        vmin = slab.lowPeak(out)
        if (vmax / slab.vref) > SAT_HIGH or (vmin / slab.vref) < SAT_LOW:
            satWarn = True

        # Find best fit
        angles = np.array(range(0, nsamples)) * 2.0 * np.pi / npoints
        # Initial guess
        mean0 = np.mean(out)
        amp0 = (vmax - vmin) / 2.0
        phase0 = 0
        # Function to optimize
        optimize_func = lambda x: x[0] * np.sin(angles + x[1]) + x[2] - out
        # Perform optimization
        amp, phase, mean = leastsq(optimize_func, [amp0, phase0, mean0])[0]

        # Warn if needed
        if satWarn:
            slab.warn("Saturated reading at ADC " + str(channel))

        # Gain to reported
        gain = amp * np.cos(phase) / amplitude + 1j * amp * np.sin(
            phase) / amplitude

        # Add to list
        list.append(gain)

    # Restore verbose level
    slab.setVerbose(prev_verbose)

    # Return the list
    return list