QE PRO software trigger demo

spectrometer_test.py

"""
needs seabreeze, pyusb, matplotlib. 
make sure pyusb can find libusb correctly.

"""

import matplotlib.pyplot as plt

import seabreeze
import seabreeze.pyseabreeze as sb
seabreeze.use('pyseabreeze')
from seabreeze.spectrometers import Spectrometer

OBP_ABORT_ACQUISITION = 0x00100000
OBP_START_BUFFERING = 0x00100902
OBP_CLEAR_BUFFER_ALL = 0x00100830

sb.protocol.OBPProtocol.msgs[OBP_ABORT_ACQUISITION] = lambda *_: b''
sb.protocol.OBPProtocol.msgs[OBP_START_BUFFERING] = lambda *_: b''
sb.protocol.OBPProtocol.msgs[OBP_CLEAR_BUFFER_ALL] = lambda *_: b''


def abort_acquisition(dev: Spectrometer):
    dev._dev._transport.protocol.send(OBP_ABORT_ACQUISITION)


def start_acquisition(dev: Spectrometer):
    dev._dev._transport.protocol.send(OBP_START_BUFFERING)


def clear_buffers(dev):
    dev._dev._transport.protocol.send(OBP_CLEAR_BUFFER_ALL)


def stop_capturing(dev: Spectrometer):
    abort_acquisition(dev)
    clear_buffers(dev)


def capture_once(dev: Spectrometer):
    """
    Start capturing a spectrum, make a capture and stop capturing.
    """
    start_acquisition(dev)
    ret = dev.intensities()
    stop_capturing(dev)
    return ret


def main():
    """Sample code that shows spectra using Matplotlib."""

    dev = Spectrometer.from_first_available()
    dev.integration_time_micros(100000)

    plt.ion()
    fig = plt.gcf()
    ax = fig.subplots()
    ax.set_xlabel('Wavelength')
    ax.set_ylabel('Intensity')
    closed = False

    def on_close(_event):
        nonlocal closed
        closed = True

    fig.canvas.mpl_connect('close_event', on_close)
    plot, = ax.plot(dev.wavelengths(), [0]*len(dev.wavelengths()))

    while not closed:
        ydata = capture_once(dev)
        plot.set_ydata(ydata)
        ax.relim()
        plt.show(block=False)
        plt.pause(0.1)


if __name__ == '__main__':
    main()