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#! /usr/bin/env python

# -*- coding: ISO-8859-1 -*-

##########################################################################

# USPP Library (Universal Serial Port Python Library)

#

# Copyright (C) 2006 Isaac Barona <ibarona@gmail.com>

# 

# This library is free software; you can redistribute it and/or

# modify it under the terms of the GNU Lesser General Public

# License as published by the Free Software Foundation; either

# version 2.1 of the License, or (at your option) any later version.

# 

# This library is distributed in the hope that it will be useful,

# but WITHOUT ANY WARRANTY; without even the implied warranty of

# MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU

# Lesser General Public License for more details.

# You should have received a copy of the GNU Lesser General Public

# License along with this library; if not, write to the Free Software

# Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA  02110-1301  USA

##########################################################################

#-------------------------------------------------------------------------

# Project:   USPP Library (Universal Serial Port Python Library)

# Name:      uspp.py

# Purpose:   Main module. Imports the correct module for the platform

#            in which it is running.

#

# Author:    Isaac Barona Martinez <ibarona@gmail.com>

# Copyright: (c) 2006 by Isaac Barona Martinez

# Licence:   LGPL

#

# Created:   26 June 2001

# History:

#            05/08/2001: Release version 0.1.

#            24/02/2006: Final version 1.0.

#

#-------------------------------------------------------------------------

"""

USPP - Universal Serial Port Python Library

This module exports a SerialPort class to access serial ports in

different platforms (currently W9X and Linux) with the same code.

When the library user import the uspp module,  it automatically

loads the correct class implementation for the platform in which

is running.

The public classes, exceptions and methods are the following:

SerialPortException

===================

Exception raised in the SerialPort methods.

SerialPort

==========

Class that encapsulate methods to access serial ports. It has the

following public methods:

* __init__(self, dev, timeout=None, speed=None, mode='232', params=None)

  Create an object to access serial port 'dev'

  Arguments:

    dev: String that indicate the name of the port. Possible values are:

        In Linux: '/dev/ttyS0', '/dev/ttyS1', ..., '/dev/ttySX' or

                  '/dev/cua0', '/dev/cua1', ..., '/dev/cuaX'

        In W9X: 'COM1', 'COM2', ..., 'COMX'

    timeout: specifies in milliseconds the inter-byte timeout. Possible

        values are:

        * None: For blocking readings. Time-outs are not used for reading

          operations.

        * 0: For non-blocking readings. The reading operation is to return

          inmediately with the characters that have already been received,

          even if no characters have been received.

        * >0: For time-out readings. A character must be read in less than

          this value.

    speed: integer that specifies the input and output baud rate to

        use. Possible values are: 110, 300, 600, 1200, 2400, 4800, 9600,

        19200, 38400, 57600 and 115200.

        If None a default speed of 9600 bps is selected.

    mode: string that specifies RS-232 or RS-485 mode. The RS-485 mode

        is half duplex and use the RTS signal to indicate the

        direction of the communication (transmit or recive).

        Posible values are: '232' or '485'. Default to RS232 mode (the

        only implemented just now).

    params: list that specifies properties of the serial communication.

        If params=None it uses default values for the number of bits

        per byte (8), the parity (NOPARITY) and the number of stop bits (1)

        else:

            * In W9X: params must be a list with three items setting up the

              these values in this order.

            * In Linux: params must is the termios package mode array to use

              for initialization.

* __del__(self):

  Destroy the SerialPort object and close the serial port. It is a good

  idea that when you finish working with the serial port you explicity

  do: del tty (where tty is a SerialPort object).

* fileno(self):

  Returns the file descriptor of the serial port. This information is

  sometimes necessary for example if you want to use the select function.

* read(self, num=1):

  Read num bytes from the serial port. Depending the timeout value used in

  the inicialitation this operation can be:

    - Blocking (if timeout=None): The operation blocks until num bytes

      arrive the serial port.

    - Non-blocking (if timeout=0): The operation returns inmediatelly

      with as many as num bytes that were waiting in the serial port to be read.

    - Time-out (if timeout>0): A byte must arrive in less milliseconds than

      the specified. If the number of read bytes is less than num a

      SerialPortException is raised because a time-out has happened.

* write(self, s):

  Write the string s to the serial port.

* inWaiting(self):

  Returns the number of bytes waiting to be read.

* flush(self):

  Discards all characters from the output or input buffer.

NOTE ON CHARACTERS AND BYTES

============================

The write and read methods of the SerialPort class expect data

in string buffers. Do not think this library only works for

ASCII communications. To interpret string elements as bytes (integer number)

you only have to use the built-in ord() function. To convert a byte

into a string element, use chr().

Example: Suppose you want to transmit the following three bytes:

0x02, 0x10, 0x30. You only have to do:

packet = ''

packet = packet + chr(0x02) + chr(0x10) + chr(0x30)

tty.write(packet)

So, you can see the bytes you send or receive as integers or as characters

depending the situation.

"""

__author__="Isaac Barona Martinez <ibarona@tid.es>"

__copyright__="""

Copyright (C) 2001 Isaac Barona Martinez <ibarona@tid.es>

This library is free software; you can redistribute it and/or

modify it under the terms of the GNU General Public License

as published by the Free Software Foundation; version 2 dated

June, 1991.

"""

__version__="0.1"

import sys

drv_ok = 0

if sys.platform=='win32':

    print "Windows platform detected:"

    #try:

    #    import notworking_d2xx

    #    from D2xxPort_win import *

    #    print "Using D2xx FTDI driver"

    #    drv_ok = 1

    #except ImportError:

    #    print "pyUSB for fast COM not found (see http://bleyer.org/pyusb/)"

    if drv_ok == 0:

        try:

            from win32file import *

            from win32event import *

            from SerialPort_win import *

            print "Using VCP FTDI driver"

        except ImportError,SerialPortException:

            print "Python for winiows extensions for COM not found"

            print "(see https://sourceforge.net/projects/pywin32/)"

            print "Could not find any usable support for FTDI chip in python"

            print "Try installing python support from one of the links."

            sys.exit()

elif sys.platform=='linux2':

    print "Linux platform detected:"

    from SerialPort_linux import *

else:

    sys.exit('Sorry, no implementation for this platform yet')