import serial  #imports the serial library...

ser = serial.Serial('COM8', 9600, timeout=1)  #create basic port connection object...
ser.close()  #close port to keep it available to other applications...

def connect():  #explicitly reconnect to serial port created above...
    if ser.isOpen() == False:
        ser.open()
        print("connected to robot...")
        return
    else:
        print("already connected...")
        return
    return

def disconnect():  #explicitly reconnect to serial port created above...
    if ser.isOpen() == True:
        ser.close()
        print("disconnected from robot...")
        return
    else:
        print("already disconnected...")
        return
    return   

def fwd():  #send command to go forward...
    if ser.isOpen() == False:
        print("not connected to a robot...")
        return
    else:
        ser.write("a")
        ser.readline()
        return
    return
    
def rev():  #send command to go reverse...
    if ser.isOpen() == False:
        print("not connected to a robot...")
        return
    else:
        ser.write("b")
        ser.readline()
        return
    return
    
def stop():  #send command to stop...
    if ser.isOpen() == False:
        print("not connected to a robot...")
        return
    else:
        ser.write("c")
        ser.readline()
        return
    return