Edit File: serialutil.py
#! python # Python Serial Port Extension for Win32, Linux, BSD, Jython # see __init__.py # # (C) 2001-2010 Chris Liechti <cliechti@gmx.net> # this is distributed under a free software license, see license.txt # compatibility for older Python < 2.6 try: bytes bytearray except (NameError, AttributeError): # Python older than 2.6 do not have these types. Like for Python 2.6 they # should behave like str. For Python older than 3.0 we want to work with # strings anyway, only later versions have a true bytes type. bytes = str # bytearray is a mutable type that is easily turned into an instance of # bytes class bytearray(list): # for bytes(bytearray()) usage def __str__(self): return ''.join(self) def __repr__(self): return 'bytearray(%r)' % ''.join(self) # append automatically converts integers to characters def append(self, item): if isinstance(item, str): list.append(self, item) else: list.append(self, chr(item)) # += def __iadd__(self, other): for byte in other: self.append(byte) return self def __getslice__(self, i, j): return bytearray(list.__getslice__(self, i, j)) def __getitem__(self, item): if isinstance(item, slice): return bytearray(list.__getitem__(self, item)) else: return ord(list.__getitem__(self, item)) def __eq__(self, other): if isinstance(other, basestring): other = bytearray(other) return list.__eq__(self, other) # all Python versions prior 3.x convert str([17]) to '[17]' instead of '\x11' # so a simple bytes(sequence) doesn't work for all versions def to_bytes(seq): """convert a sequence to a bytes type""" b = bytearray() for item in seq: b.append(item) # this one handles int and str return bytes(b) # create control bytes XON = to_bytes([17]) XOFF = to_bytes([19]) CR = to_bytes([13]) LF = to_bytes([10]) PARITY_NONE, PARITY_EVEN, PARITY_ODD, PARITY_MARK, PARITY_SPACE = 'N', 'E', 'O', 'M', 'S' STOPBITS_ONE, STOPBITS_ONE_POINT_FIVE, STOPBITS_TWO = (1, 1.5, 2) FIVEBITS, SIXBITS, SEVENBITS, EIGHTBITS = (5, 6, 7, 8) PARITY_NAMES = { PARITY_NONE: 'None', PARITY_EVEN: 'Even', PARITY_ODD: 'Odd', PARITY_MARK: 'Mark', PARITY_SPACE: 'Space', } class SerialException(IOError): """Base class for serial port related exceptions.""" class SerialTimeoutException(SerialException): """Write timeouts give an exception""" writeTimeoutError = SerialTimeoutException("Write timeout") portNotOpenError = ValueError('Attempting to use a port that is not open') class FileLike(object): """An abstract file like class. This class implements readline and readlines based on read and writelines based on write. This class is used to provide the above functions for to Serial port objects. Note that when the serial port was opened with _NO_ timeout that readline blocks until it sees a newline (or the specified size is reached) and that readlines would never return and therefore refuses to work (it raises an exception in this case)! """ def __init__(self): self.closed = True def close(self): self.closed = True # so that ports are closed when objects are discarded def __del__(self): """Destructor. Calls close().""" # The try/except block is in case this is called at program # exit time, when it's possible that globals have already been # deleted, and then the close() call might fail. Since # there's nothing we can do about such failures and they annoy # the end users, we suppress the traceback. try: self.close() except: pass def writelines(self, sequence): for line in sequence: self.write(line) def flush(self): """flush of file like objects""" pass # iterator for e.g. "for line in Serial(0): ..." usage def next(self): line = self.readline() if not line: raise StopIteration return line def __iter__(self): return self def readline(self, size=None, eol=LF): """read a line which is terminated with end-of-line (eol) character ('\n' by default) or until timeout.""" leneol = len(eol) line = bytearray() while True: c = self.read(1) if c: line += c if line[-leneol:] == eol: break if size is not None and len(line) >= size: break else: break return bytes(line) def readlines(self, sizehint=None, eol=LF): """read a list of lines, until timeout. sizehint is ignored.""" if self.timeout is None: raise ValueError("Serial port MUST have enabled timeout for this function!") leneol = len(eol) lines = [] while True: line = self.readline(eol=eol) if line: lines.append(line) if line[-leneol:] != eol: # was the line received with a timeout? break else: break return lines def xreadlines(self, sizehint=None): """Read lines, implemented as generator. It will raise StopIteration on timeout (empty read). sizehint is ignored.""" while True: line = self.readline() if not line: break yield line # other functions of file-likes - not used by pySerial #~ readinto(b) def seek(self, pos, whence=0): raise IOError("file is not seekable") def tell(self): raise IOError("file is not seekable") def truncate(self, n=None): raise IOError("file is not seekable") def isatty(self): return False class SerialBase(object): """Serial port base class. Provides __init__ function and properties to get/set port settings.""" # default values, may be overridden in subclasses that do not support all values BAUDRATES = (50, 75, 110, 134, 150, 200, 300, 600, 1200, 1800, 2400, 4800, 9600, 19200, 38400, 57600, 115200, 230400, 460800, 500000, 576000, 921600, 1000000, 1152000, 1500000, 2000000, 2500000, 3000000, 3500000, 4000000) BYTESIZES = (FIVEBITS, SIXBITS, SEVENBITS, EIGHTBITS) PARITIES = (PARITY_NONE, PARITY_EVEN, PARITY_ODD, PARITY_MARK, PARITY_SPACE) STOPBITS = (STOPBITS_ONE, STOPBITS_ONE_POINT_FIVE, STOPBITS_TWO) def __init__(self, port = None, # number of device, numbering starts at # zero. if everything fails, the user # can specify a device string, note # that this isn't portable anymore # port will be opened if one is specified baudrate=9600, # baud rate bytesize=EIGHTBITS, # number of data bits parity=PARITY_NONE, # enable parity checking stopbits=STOPBITS_ONE, # number of stop bits timeout=None, # set a timeout value, None to wait forever xonxoff=False, # enable software flow control rtscts=False, # enable RTS/CTS flow control writeTimeout=None, # set a timeout for writes dsrdtr=False, # None: use rtscts setting, dsrdtr override if True or False interCharTimeout=None # Inter-character timeout, None to disable ): """Initialize comm port object. If a port is given, then the port will be opened immediately. Otherwise a Serial port object in closed state is returned.""" self._isOpen = False self._port = None # correct value is assigned below through properties self._baudrate = None # correct value is assigned below through properties self._bytesize = None # correct value is assigned below through properties self._parity = None # correct value is assigned below through properties self._stopbits = None # correct value is assigned below through properties self._timeout = None # correct value is assigned below through properties self._writeTimeout = None # correct value is assigned below through properties self._xonxoff = None # correct value is assigned below through properties self._rtscts = None # correct value is assigned below through properties self._dsrdtr = None # correct value is assigned below through properties self._interCharTimeout = None # correct value is assigned below through properties # assign values using get/set methods using the properties feature self.port = port self.baudrate = baudrate self.bytesize = bytesize self.parity = parity self.stopbits = stopbits self.timeout = timeout self.writeTimeout = writeTimeout self.xonxoff = xonxoff self.rtscts = rtscts self.dsrdtr = dsrdtr self.interCharTimeout = interCharTimeout if port is not None: self.open() def isOpen(self): """Check if the port is opened.""" return self._isOpen # - - - - - - - - - - - - - - - - - - - - - - - - # TODO: these are not really needed as the is the BAUDRATES etc. attribute... # maybe i remove them before the final release... def getSupportedBaudrates(self): return [(str(b), b) for b in self.BAUDRATES] def getSupportedByteSizes(self): return [(str(b), b) for b in self.BYTESIZES] def getSupportedStopbits(self): return [(str(b), b) for b in self.STOPBITS] def getSupportedParities(self): return [(PARITY_NAMES[b], b) for b in self.PARITIES] # - - - - - - - - - - - - - - - - - - - - - - - - def setPort(self, port): """Change the port. The attribute portstr is set to a string that contains the name of the port.""" was_open = self._isOpen if was_open: self.close() if port is not None: if isinstance(port, basestring): self.portstr = port else: self.portstr = self.makeDeviceName(port) else: self.portstr = None self._port = port self.name = self.portstr if was_open: self.open() def getPort(self): """Get the current port setting. The value that was passed on init or using setPort() is passed back. See also the attribute portstr which contains the name of the port as a string.""" return self._port port = property(getPort, setPort, doc="Port setting") def setBaudrate(self, baudrate): """Change baud rate. It raises a ValueError if the port is open and the baud rate is not possible. If the port is closed, then the value is accepted and the exception is raised when the port is opened.""" try: self._baudrate = int(baudrate) except TypeError: raise ValueError("Not a valid baudrate: %r" % (baudrate,)) else: if self._isOpen: self._reconfigurePort() def getBaudrate(self): """Get the current baud rate setting.""" return self._baudrate baudrate = property(getBaudrate, setBaudrate, doc="Baud rate setting") def setByteSize(self, bytesize): """Change byte size.""" if bytesize not in self.BYTESIZES: raise ValueError("Not a valid byte size: %r" % (bytesize,)) self._bytesize = bytesize if self._isOpen: self._reconfigurePort() def getByteSize(self): """Get the current byte size setting.""" return self._bytesize bytesize = property(getByteSize, setByteSize, doc="Byte size setting") def setParity(self, parity): """Change parity setting.""" if parity not in self.PARITIES: raise ValueError("Not a valid parity: %r" % (parity,)) self._parity = parity if self._isOpen: self._reconfigurePort() def getParity(self): """Get the current parity setting.""" return self._parity parity = property(getParity, setParity, doc="Parity setting") def setStopbits(self, stopbits): """Change stop bits size.""" if stopbits not in self.STOPBITS: raise ValueError("Not a valid stop bit size: %r" % (stopbits,)) self._stopbits = stopbits if self._isOpen: self._reconfigurePort() def getStopbits(self): """Get the current stop bits setting.""" return self._stopbits stopbits = property(getStopbits, setStopbits, doc="Stop bits setting") def setTimeout(self, timeout): """Change timeout setting.""" if timeout is not None: try: timeout + 1 # test if it's a number, will throw a TypeError if not... except TypeError: raise ValueError("Not a valid timeout: %r" % (timeout,)) if timeout < 0: raise ValueError("Not a valid timeout: %r" % (timeout,)) self._timeout = timeout if self._isOpen: self._reconfigurePort() def getTimeout(self): """Get the current timeout setting.""" return self._timeout timeout = property(getTimeout, setTimeout, doc="Timeout setting for read()") def setWriteTimeout(self, timeout): """Change timeout setting.""" if timeout is not None: if timeout < 0: raise ValueError("Not a valid timeout: %r" % (timeout,)) try: timeout + 1 #test if it's a number, will throw a TypeError if not... except TypeError: raise ValueError("Not a valid timeout: %r" % timeout) self._writeTimeout = timeout if self._isOpen: self._reconfigurePort() def getWriteTimeout(self): """Get the current timeout setting.""" return self._writeTimeout writeTimeout = property(getWriteTimeout, setWriteTimeout, doc="Timeout setting for write()") def setXonXoff(self, xonxoff): """Change XON/XOFF setting.""" self._xonxoff = xonxoff if self._isOpen: self._reconfigurePort() def getXonXoff(self): """Get the current XON/XOFF setting.""" return self._xonxoff xonxoff = property(getXonXoff, setXonXoff, doc="XON/XOFF setting") def setRtsCts(self, rtscts): """Change RTS/CTS flow control setting.""" self._rtscts = rtscts if self._isOpen: self._reconfigurePort() def getRtsCts(self): """Get the current RTS/CTS flow control setting.""" return self._rtscts rtscts = property(getRtsCts, setRtsCts, doc="RTS/CTS flow control setting") def setDsrDtr(self, dsrdtr=None): """Change DsrDtr flow control setting.""" if dsrdtr is None: # if not set, keep backwards compatibility and follow rtscts setting self._dsrdtr = self._rtscts else: # if defined independently, follow its value self._dsrdtr = dsrdtr if self._isOpen: self._reconfigurePort() def getDsrDtr(self): """Get the current DSR/DTR flow control setting.""" return self._dsrdtr dsrdtr = property(getDsrDtr, setDsrDtr, "DSR/DTR flow control setting") def setInterCharTimeout(self, interCharTimeout): """Change inter-character timeout setting.""" if interCharTimeout is not None: if interCharTimeout < 0: raise ValueError("Not a valid timeout: %r" % interCharTimeout) try: interCharTimeout + 1 # test if it's a number, will throw a TypeError if not... except TypeError: raise ValueError("Not a valid timeout: %r" % interCharTimeout) self._interCharTimeout = interCharTimeout if self._isOpen: self._reconfigurePort() def getInterCharTimeout(self): """Get the current inter-character timeout setting.""" return self._interCharTimeout interCharTimeout = property(getInterCharTimeout, setInterCharTimeout, doc="Inter-character timeout setting for read()") # - - - - - - - - - - - - - - - - - - - - - - - - _SETTINGS = ('baudrate', 'bytesize', 'parity', 'stopbits', 'xonxoff', 'dsrdtr', 'rtscts', 'timeout', 'writeTimeout', 'interCharTimeout') def getSettingsDict(self): """Get current port settings as a dictionary. For use with applySettingsDict""" return dict([(key, getattr(self, '_'+key)) for key in self._SETTINGS]) def applySettingsDict(self, d): """apply stored settings from a dictionary returned from getSettingsDict. it's allowed to delete keys from the dictionary. these values will simply left unchanged.""" for key in self._SETTINGS: if d[key] != getattr(self, '_'+key): # check against internal "_" value setattr(self, key, d[key]) # set non "_" value to use properties write function # - - - - - - - - - - - - - - - - - - - - - - - - def __repr__(self): """String representation of the current port settings and its state.""" return "%s<id=0x%x, open=%s>(port=%r, baudrate=%r, bytesize=%r, parity=%r, stopbits=%r, timeout=%r, xonxoff=%r, rtscts=%r, dsrdtr=%r)" % ( self.__class__.__name__, id(self), self._isOpen, self.portstr, self.baudrate, self.bytesize, self.parity, self.stopbits, self.timeout, self.xonxoff, self.rtscts, self.dsrdtr, ) # - - - - - - - - - - - - - - - - - - - - - - - - # compatibility with io library def readable(self): return True def writable(self): return True def seekable(self): return False def readinto(self, b): data = self.read(len(b)) n = len(data) try: b[:n] = data except TypeError, err: import array if not isinstance(b, array.array): raise err b[:n] = array.array('b', data) return n if __name__ == '__main__': import sys s = SerialBase() sys.stdout.write('port name: %s\n' % s.portstr) sys.stdout.write('baud rates: %s\n' % s.getSupportedBaudrates()) sys.stdout.write('byte sizes: %s\n' % s.getSupportedByteSizes()) sys.stdout.write('parities: %s\n' % s.getSupportedParities()) sys.stdout.write('stop bits: %s\n' % s.getSupportedStopbits()) sys.stdout.write('%s\n' % s)