Source code for CustomArduinoDevice.simSerialPort

"""Simulate the serial port for the CustomArduinoDevice.

Sometimes you do not have the real Arduino at hand. So here, we just simulate its
response for simpler testing remotely.
"""

import os, pty
import time
import numpy as np

def test_serial():
    """The function that initializes the serial port.

    Returns:
        Nothing really. Just sets things up.
    """
    setpoint  = 750;
    master, slave = pty.openpty()
    s_name = os.ttyname(slave)
    print(s_name)
    while True:
        meas = np.random.randint(700, 800)
        err = setpoint - meas;
        control = np.random.randint(10)
        gain =1
        tauI = 100
        tauD = 1
        mode = os.read(master, 1);
        if mode:
            print('mode {}'.format(mode))
            if mode == b'w':
                ard_str = str(setpoint) + ',' + str(meas) + ',' + str(err) + ',' + str(control)
                ard_str = ard_str + ',' + str(gain) + ',' + str(tauI) +',' + str(tauD) + '\r\n'
                out = ard_str.encode('windows-1252')
                os.write(master, out)
            if mode == b's':
                set = os.read(master, 20);
                setpoint = int(set.decode('windows-1252'));
                print('s{}'.format(setpoint));
        time.sleep(0.1)

if __name__=='__main__':
    test_serial()