How to sniff a serial connection of a Java app

Question

I'm trying to discover the connection parameters to a Java application. According to the status bar on the Java app, the connection values are: com1, 4800-baudrate, 8-eightbits, 1-stopbits, e-parity). However, when using pySerial to make a connection to the device (embedded Linux device -Ubuntu), I'm getting an access denied response. I feel that com1 is being used with a port number or something. At any rate, here is what I'm using:

import serial
import time

ser = serial.Serial(
       port='COM1',
       baudrate=4800,
       parity=serial.PARITY_EVEN,
       stopbits=serial.STOPBITS_ONE,
       bytesize=serial.EIGHTBITS)


ser.open()
ser.isOpen()


print ser.baudrate()

Error:

Traceback (most recent call last):
File "C:\Users\me\Desktop\file.py", line 12, in <module>
ser.open()
File "C:\Python27\lib\site-packages\serial\serialwin32.py", line 56, in open
raise SerialException("could not open port %s: %s" % (self.portstr, ctypes.WinError()))
SerialException: could not open port COM1: [Error 5] Access is denied.

I appreciate any help and/or direction given.

Two processes cannot access the same serial port at the same time. — John Dvorak
Yeah, I know. I close the Java app, when I attempt with pySerial. — suffa
These questions probably have a solution for your problem: stackoverflow.com/questions/6032568/using-serial-on-python-win7 stackoverflow.com/questions/8290913/… stackoverflow.com/questions/2063257/… — Pedro Romano

Sabri Dilmaç Sabri Dilmaç · Accepted Answer · 2013-01-07T18:27:32

You cant open if already is open(try com port spliting with anyone software) serial splitter İf you got 2 serial port, make sniffer with a cable...

Best regards

How to sniff a serial connection of a Java app

1 Answers