Connecting to a Cisco switch via console cable through a serial port with a laptop using Python3 (pySerial)

serial_conn.py

__author__ = "Tanner Ray Martin & Osama Abbas"
__version__ = "1.1.0"

import time

import serial

# Creating your serial object
ser_conn = serial.Serial(
    port="COM3",  # COM is on windows, linux is different
    baudrate=serial.Serial.BAUDRATES[12],  # 9600
    parity=serial.PARITY_NONE,  #'N'
    stopbits=serial.STOPBITS_ONE,  # 1
    bytesize=serial.EIGHTBITS,  # 8
    timeout=20,  # 20 seconds seems to be a good timeout, may need to be increased
)

# Open your serial object
ser_conn.isOpen()

# In this case it returns str COM3
print(ser_conn.name)

# First command (hitting enter)
command = "\r\n"

# Convert str to binary (commands sent to switch must be binary)
command = str.encode(command)

# Send the command to the switch
ser_conn.write(command)

# Wait a sec
time.sleep(1)
ser_conn.inWaiting()

# Get the response from the switch
input_data = ser_conn.read(225)  # (how many bytes to limit to read)

# Convert binary to str
input_data = input_data.decode("utf-8", "ignore")

# Print response
print(input_data)

# Create a loop
while True:
    # Enter your own command
    command = input(":: ")

    # Type 'exit' to end serial session with the switch
    if command == "exit":
        ser_conn.close()
        exit()
    else:
        # Convert command to binary
        command = str.encode(command + "\r\n")

        # Send command
        ser_conn.write(command)

        # Set response variable (empty binary str)
        out = b""

        # Take a short nap
        time.sleep(1)

        # While response is happening (timeout hasnt expired)
        while ser_conn.inWaiting() > 0:

            # Trying to read one line at a time (100 bytes at a time)
            out = ser_conn.readline(100)

            # Converting response to str
            out = out.decode("utf-8", "ignore")

            # Printing response if not empty
            if out != "":
                print(out)

            # Repeat until timeout