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#! /usr/bin/python
#Python Serial Port Extension for Win32, Linux, BSD, Jython
#serial driver for win32
#see __init__.py
#
#(C) 2001-2003 Chris Liechti <cliechti@gmx.net>
# this is distributed under a free software license, see license.txt
import win32file # The base COM port and file IO functions.
import win32event # We use events and the WaitFor[Single|Multiple]Objects functions.
import win32con # constants.
from serialutil import *
VERSION = "$Revision: 1.40 $".split()[1] #extract CVS version
#from winbase.h. these should realy be in win32con
MS_CTS_ON = 16
MS_DSR_ON = 32
MS_RING_ON = 64
MS_RLSD_ON = 128
def device(portnum):
"""Turn a port number into a device name"""
return 'COM%d' % (portnum+1) #numbers are transformed to a string
class Serial(SerialBase):
"""Serial port implemenation for Win32. This implemenatation requires a
win32all installation."""
BAUDRATES = (50,75,110,134,150,200,300,600,1200,1800,2400,4800,9600,
19200,38400,57600,115200)
def open(self):
"""Open port with current settings. This may throw a SerialException
if the port cannot be opened."""
if self._port is None:
raise SerialException("Port must be configured before it can be used.")
self.hComPort = None
try:
self.hComPort = win32file.CreateFile(self.makeDeviceName(self.portstr),
win32con.GENERIC_READ | win32con.GENERIC_WRITE,
0, # exclusive access
None, # no security
win32con.OPEN_EXISTING,
win32con.FILE_FLAG_OVERLAPPED,
None)
except Exception, msg:
self.hComPort = None #'cause __del__ is called anyway
raise SerialException("could not open port %s: %s" % (self.portstr, msg))
# Setup a 4k buffer
win32file.SetupComm(self.hComPort, 4096, 4096)
#Save original timeout values:
self._orgTimeouts = win32file.GetCommTimeouts(self.hComPort)
self._rtsState = win32file.RTS_CONTROL_ENABLE
self._dtrState = win32file.DTR_CONTROL_ENABLE
self._reconfigurePort()
# Clear buffers:
# Remove anything that was there
win32file.PurgeComm(self.hComPort,
win32file.PURGE_TXCLEAR | win32file.PURGE_TXABORT |
win32file.PURGE_RXCLEAR | win32file.PURGE_RXABORT)
self._overlappedRead = win32file.OVERLAPPED()
self._overlappedRead.hEvent = win32event.CreateEvent(None, 1, 0, None)
self._overlappedWrite = win32file.OVERLAPPED()
#~ self._overlappedWrite.hEvent = win32event.CreateEvent(None, 1, 0, None)
self._overlappedWrite.hEvent = win32event.CreateEvent(None, 0, 0, None)
self._isOpen = True
def _reconfigurePort(self):
"""Set commuication parameters on opened port."""
if not self.hComPort:
raise SerialException("Can only operate on a valid port handle")
#Set Windows timeout values
#timeouts is a tuple with the following items:
#(ReadIntervalTimeout,ReadTotalTimeoutMultiplier,
# ReadTotalTimeoutConstant,WriteTotalTimeoutMultiplier,
# WriteTotalTimeoutConstant)
if self._timeout is None:
timeouts = (0, 0, 0, 0, 0)
elif self._timeout == 0:
timeouts = (win32con.MAXDWORD, 0, 0, 0, 0)
else:
timeouts = (0, 0, int(self._timeout*1000), 0, 0)
if self._writeTimeout is None:
pass
elif self._writeTimeout == 0:
timeouts = timeouts[:-2] + (0, win32con.MAXDWORD)
else:
timeouts = timeouts[:-2] + (0, int(self._writeTimeout*1000))
win32file.SetCommTimeouts(self.hComPort, timeouts)
win32file.SetCommMask(self.hComPort, win32file.EV_ERR)
# Setup the connection info.
# Get state and modify it:
comDCB = win32file.GetCommState(self.hComPort)
comDCB.BaudRate = self._baudrate
if self._bytesize == FIVEBITS:
comDCB.ByteSize = 5
elif self._bytesize == SIXBITS:
comDCB.ByteSize = 6
elif self._bytesize == SEVENBITS:
comDCB.ByteSize = 7
elif self._bytesize == EIGHTBITS:
comDCB.ByteSize = 8
else:
raise ValueError("Unsupported number of data bits: %r" % self._bytesize)
if self._parity == PARITY_NONE:
comDCB.Parity = win32file.NOPARITY
comDCB.fParity = 0 # Dis/Enable Parity Check
elif self._parity == PARITY_EVEN:
comDCB.Parity = win32file.EVENPARITY
comDCB.fParity = 1 # Dis/Enable Parity Check
elif self._parity == PARITY_ODD:
comDCB.Parity = win32file.ODDPARITY
comDCB.fParity = 1 # Dis/Enable Parity Check
else:
raise ValueError("Unsupported parity mode: %r" % self._parity)
if self._stopbits == STOPBITS_ONE:
comDCB.StopBits = win32file.ONESTOPBIT
elif self._stopbits == STOPBITS_TWO:
comDCB.StopBits = win32file.TWOSTOPBITS
else:
raise ValueError("Unsupported number of stop bits: %r" % self._stopbits)
comDCB.fBinary = 1 # Enable Binary Transmission
# Char. w/ Parity-Err are replaced with 0xff (if fErrorChar is set to TRUE)
if self._rtscts:
comDCB.fRtsControl = win32file.RTS_CONTROL_HANDSHAKE
else:
comDCB.fRtsControl = self._rtsState
if self._dsrdtr:
comDCB.fDtrControl = win32file.DTR_CONTROL_HANDSHAKE
else:
comDCB.fDtrControl = self._dtrState
comDCB.fOutxCtsFlow = self._rtscts
comDCB.fOutxDsrFlow = self._dsrdtr
comDCB.fOutX = self._xonxoff
comDCB.fInX = self._xonxoff
comDCB.fNull = 0
comDCB.fErrorChar = 0
comDCB.fAbortOnError = 0
comDCB.XonChar = XON
comDCB.XoffChar = XOFF
try:
win32file.SetCommState(self.hComPort, comDCB)
except win32file.error, e:
raise ValueError("Cannot configure port, some setting was wrong. Original message: %s" % e)
#~ def __del__(self):
#~ self.close()
def close(self):
"""Close port"""
if self._isOpen:
if self.hComPort:
try:
# Restore original timeout values:
win32file.SetCommTimeouts(self.hComPort, self._orgTimeouts)
except win32file.error:
# ignore errors. can happen for unplugged USB serial devices
pass
# Close COM-Port:
win32file.CloseHandle(self.hComPort)
win32file.CloseHandle(self._overlappedRead.hEvent)
win32file.CloseHandle(self._overlappedWrite.hEvent)
self.hComPort = None
self._isOpen = False
def makeDeviceName(self, port):
# the "\\.\COMx" format is required for devices other than COM1-COM8
# not all versions of windows seem to support this properly
# so that the first few ports are used with the DOS device name
if port.upper().startswith('COM') and int(port[3:]) <= 8:
return port
return '\\\\.\\' + port
# - - - - - - - - - - - - - - - - - - - - - - - -
def inWaiting(self):
"""Return the number of characters currently in the input buffer."""
flags, comstat = win32file.ClearCommError(self.hComPort)
return comstat.cbInQue
def read(self, size=1):
"""Read size bytes from the serial port. If a timeout is set it may
return less characters as requested. With no timeout it will block
until the requested number of bytes is read."""
if not self.hComPort: raise portNotOpenError
if size > 0:
win32event.ResetEvent(self._overlappedRead.hEvent)
flags, comstat = win32file.ClearCommError(self.hComPort)
if self.timeout == 0:
n = min(comstat.cbInQue, size)
if n > 0:
rc, buf = win32file.ReadFile(self.hComPort, win32file.AllocateReadBuffer(n), self._overlappedRead)
win32event.WaitForSingleObject(self._overlappedRead.hEvent, win32event.INFINITE)
read = str(buf)
else:
read = ''
else:
rc, buf = win32file.ReadFile(self.hComPort, win32file.AllocateReadBuffer(size), self._overlappedRead)
n = win32file.GetOverlappedResult(self.hComPort, self._overlappedRead, 1)
read = str(buf[:n])
else:
read = ''
return read
def write(self, data):
"""Output the given string over the serial port."""
if not self.hComPort: raise portNotOpenError
if not isinstance(data, str):
raise TypeError('expected str, got %s' % type(data))
#print repr(s),
if data:
#~ win32event.ResetEvent(self._overlappedWrite.hEvent)
err, n = win32file.WriteFile(self.hComPort, data, self._overlappedWrite)
if err: #will be ERROR_IO_PENDING:
# Wait for the write to complete.
#~ win32event.WaitForSingleObject(self._overlappedWrite.hEvent, win32event.INFINITE)
n = win32file.GetOverlappedResult(self.hComPort, self._overlappedWrite, 1)
if n != len(data):
raise writeTimeoutError
def flushInput(self):
"""Clear input buffer, discarding all that is in the buffer."""
if not self.hComPort: raise portNotOpenError
win32file.PurgeComm(self.hComPort, win32file.PURGE_RXCLEAR | win32file.PURGE_RXABORT)
def flushOutput(self):
"""Clear output buffer, aborting the current output and
discarding all that is in the buffer."""
if not self.hComPort: raise portNotOpenError
win32file.PurgeComm(self.hComPort, win32file.PURGE_TXCLEAR | win32file.PURGE_TXABORT)
def sendBreak(self, duration=0.25):
"""Send break condition."""
if not self.hComPort: raise portNotOpenError
import time
win32file.SetCommBreak(self.hComPort)
time.sleep(duration)
win32file.ClearCommBreak(self.hComPort)
def setRTS(self, level=1):
"""Set terminal status line: Request To Send"""
if not self.hComPort: raise portNotOpenError
if level:
self._rtsState = win32file.RTS_CONTROL_ENABLE
win32file.EscapeCommFunction(self.hComPort, win32file.SETRTS)
else:
self._rtsState = win32file.RTS_CONTROL_DISABLE
win32file.EscapeCommFunction(self.hComPort, win32file.CLRRTS)
def setDTR(self, level=1):
"""Set terminal status line: Data Terminal Ready"""
if not self.hComPort: raise portNotOpenError
if level:
self._dtrState = win32file.DTR_CONTROL_ENABLE
win32file.EscapeCommFunction(self.hComPort, win32file.SETDTR)
else:
self._dtrState = win32file.DTR_CONTROL_DISABLE
win32file.EscapeCommFunction(self.hComPort, win32file.CLRDTR)
def getCTS(self):
"""Read terminal status line: Clear To Send"""
if not self.hComPort: raise portNotOpenError
return MS_CTS_ON & win32file.GetCommModemStatus(self.hComPort) != 0
def getDSR(self):
"""Read terminal status line: Data Set Ready"""
if not self.hComPort: raise portNotOpenError
return MS_DSR_ON & win32file.GetCommModemStatus(self.hComPort) != 0
def getRI(self):
"""Read terminal status line: Ring Indicator"""
if not self.hComPort: raise portNotOpenError
return MS_RING_ON & win32file.GetCommModemStatus(self.hComPort) != 0
def getCD(self):
"""Read terminal status line: Carrier Detect"""
if not self.hComPort: raise portNotOpenError
return MS_RLSD_ON & win32file.GetCommModemStatus(self.hComPort) != 0
# - - platform specific - - - -
def setXON(self, level=True):
"""Platform specific - set flow state."""
if not self.hComPort: raise portNotOpenError
if level:
win32file.EscapeCommFunction(self.hComPort, win32file.SETXON)
else:
win32file.EscapeCommFunction(self.hComPort, win32file.SETXOFF)
#Nur Testfunktion!!
if __name__ == '__main__':
s = Serial(0)
print s
s = Serial()
print s
s.baudrate = 19200
s.databits = 7
s.close()
s.port = 0
s.open()
print s
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