# sermsdos.py
#
# History:
#
# 3rd September 2002 Dave Haynes
# 1. First defined
#
# Although this code should run under the latest versions of
# Python, on DOS-based platforms such as Windows 95 and 98,
# it has been specifically written to be compatible with
# PyDOS, available at:
# http://www.python.org/ftp/python/wpy/dos.html
#
# PyDOS is a stripped-down version of Python 1.5.2 for
# DOS machines. Therefore, in making changes to this file,
# please respect Python 1.5.2 syntax. In addition, please
# limit the width of this file to 60 characters.
#
# Note also that the modules in PyDOS contain fewer members
# than other versions, so we are restricted to using the
# following:
#
# In module os:
# -------------
# environ, chdir, getcwd, getpid, umask, fdopen, close,
# dup, dup2, fstat, lseek, open, read, write, O_RDONLY,
# O_WRONLY, O_RDWR, O_APPEND, O_CREAT, O_EXCL, O_TRUNC,
# access, F_OK, R_OK, W_OK, X_OK, chmod, listdir, mkdir,
# remove, rename, renames, rmdir, stat, unlink, utime,
# execl, execle, execlp, execlpe, execvp, execvpe, _exit,
# system.
#
# In module os.path:
# ------------------
# curdir, pardir, sep, altsep, pathsep, defpath, linesep.
#
import os
import sys
import string
import serialutil
BAUD_RATES = {
110: "11",
150: "15",
300: "30",
600: "60",
1200: "12",
2400: "24",
4800: "48",
9600: "96",
19200: "19"}
(PARITY_NONE, PARITY_EVEN, PARITY_ODD, PARITY_MARK,
PARITY_SPACE) = (0, 1, 2, 3, 4)
(STOPBITS_ONE, STOPBITS_ONEANDAHALF,
STOPBITS_TWO) = (1, 1.5, 2)
FIVEBITS, SIXBITS, SEVENBITS, EIGHTBITS = (5, 6, 7, 8)
(RETURN_ERROR, RETURN_BUSY, RETURN_RETRY, RETURN_READY,
RETURN_NONE) = ('E', 'B', 'P', 'R', 'N')
portNotOpenError = ValueError('port not open')
def device(portnum):
return 'COM%d' % (portnum+1)
class Serial(serialutil.FileLike):
"""
port: number of device; numbering starts at
zero. if everything fails, the user can
specify a device string, note that this
isn't portable any more
baudrate: baud rate
bytesize: number of databits
parity: enable parity checking
stopbits: number of stopbits
timeout: set a timeout (None for waiting forever)
xonxoff: enable software flow control
rtscts: enable RTS/CTS flow control
retry: DOS retry mode
"""
def __init__(self,
port,
baudrate = 9600,
bytesize = EIGHTBITS,
parity = PARITY_NONE,
stopbits = STOPBITS_ONE,
timeout = None,
xonxoff = 0,
rtscts = 0,
retry = RETURN_RETRY
):
if type(port) == type(''):
# strings are taken directly
self.portstr = port
else:
# numbers are transformed to a string
self.portstr = device(port+1)
self.baud = BAUD_RATES[baudrate]
self.bytesize = str(bytesize)
if parity == PARITY_NONE:
self.parity = 'N'
elif parity == PARITY_EVEN:
self.parity = 'E'
elif parity == PARITY_ODD:
self.parity = 'O'
elif parity == PARITY_MARK:
self.parity = 'M'
elif parity == PARITY_SPACE:
self.parity = 'S'
self.stop = str(stopbits)
self.retry = retry
self.filename = "sermsdos.tmp"
self._config(self.portstr, self.baud, self.parity,
self.bytesize, self.stop, self.retry, self.filename)
def __del__(self):
self.close()
def close(self):
pass
def _config(self, port, baud, parity, data, stop, retry,
filename):
comString = string.join(("MODE ", port, ":"
, " BAUD= ", baud, " PARITY= ", parity
, " DATA= ", data, " STOP= ", stop, " RETRY= ",
retry, " > ", filename ), '')
os.system(comString)
def setBaudrate(self, baudrate):
self._config(self.portstr, BAUD_RATES[baudrate],
self.parity, self.bytesize, self.stop, self.retry,
self.filename)
def inWaiting(self):
"""returns the number of bytes waiting to be read"""
raise NotImplementedError
def read(self, num = 1):
"""Read num bytes from serial port"""
handle = os.open(self.portstr,
os.O_RDONLY | os.O_BINARY)
rv = os.read(handle, num)
os.close(handle)
return rv
def write(self, s):
"""Write string to serial port"""
handle = os.open(self.portstr,
os.O_WRONLY | os.O_BINARY)
rv = os.write(handle, s)
os.close(handle)
return rv
def flushInput(self):
raise NotImplementedError
def flushOutput(self):
raise NotImplementedError
def sendBreak(self):
raise NotImplementedError
def setRTS(self,level=1):
"""Set terminal status line"""
raise NotImplementedError
def setDTR(self,level=1):
"""Set terminal status line"""
raise NotImplementedError
def getCTS(self):
"""Eead terminal status line"""
raise NotImplementedError
def getDSR(self):
"""Eead terminal status line"""
raise NotImplementedError
def getRI(self):
"""Eead terminal status line"""
raise NotImplementedError
def getCD(self):
"""Eead terminal status line"""
raise NotImplementedError
def __repr__(self):
return string.join(( "<Serial>: ", self.portstr
, self.baud, self.parity, self.bytesize, self.stop,
self.retry , self.filename), ' ')
if __name__ == '__main__':
s = Serial(0)
sys.stdio.write('%s %s\n' % (__name__, s))
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