import os, pty, time, struct, math

def ascii_test(port):

    """Put ASCII test data through pseudo terminal."""

    print("\n")

    nc = 4 # number of channels

    for i in range(0, 1000):

        data = []

        for ci in range(0, nc):

            data.append(i*(ci+1))

        data = ",".join([str(num) for num in data])

        print("<< " + data, end="\r")

        os.write(port, bytes(data + "\r\n", 'ASCII'))

        time.sleep(0.1)

def float_test(port):

    """Put 32-bit float test data through pseudo terminal"""

    for i in range(0, 1000):

        f = float(i)/3.0

        data = struct.pack('f', f)

        os.write(port, data)

        import binascii

        time.sleep(0.1)

def float_sine(port):

    """Puts 2 channel sine and cosine wafeform through pseudo terminal

    continuously."""

    i = 0

    period = 200

    while True:

        sin = math.sin(2 * math.pi * i / period)

        # cos = math.sin(2 * math.pi * (i / period + 1 / 4))

        data = struct.pack('ff', sin, -sin)

        os.write(port, data)

        i = (i + 1) % period

        time.sleep(0.1)

def uint32_test(port, little):

    """Puts 32 bit unsigned integer data through pseudo terminal"""

    i = 0

    maxi = 200

    while True:

        data = struct.pack('>I', i)

        os.write(port, data)

        time.sleep(0.05)

        i = i+1 if i <= maxi else 0

def run():

    # create the pseudo terminal

    master, slave = pty.openpty()

    master_name = os.ttyname(master)

    slave_name = os.ttyname(slave)

    print("Master terminal: {}\nSlave terminal: {}".format(master_name, slave_name))

    try:

    finally:

        # close the pseudo terminal files

        os.close(master)

        os.close(slave)

if __name__=="__main__":

    run()