python操作串口的库 pyserial

因为考虑到跨平台，可能要布署在linux，再结合开发的容易度，最终认为python在这方面有一定的优势

做短信收发主要是用于：

1，用户快速注册

2，用户绑定手机

3，密码安全

4，重要通知（短信群发）

Short introduction

Open port 0 at "9600,8,N,1", no timeout

>>> import serial
>>> ser = serial.Serial(0)  #open first serial port
>>> print ser.portstr       #check which port was really used
>>> ser.write("hello")      #write a string
>>> ser.close()             #close port

Open named port at "19200,8,N,1", 1s timeout

>>> ser = serial.Serial('/dev/ttyS1', 19200, timeout=1)
>>> x = ser.read()          #read one byte
>>> s = ser.read(10)        #read up to ten bytes (timeout)
>>> line = ser.readline()   #read a '\n' terminated line
>>> ser.close()

Open second port at "38400,8,E,1", non blocking HW handshaking

>>> ser = serial.Serial(1, 38400, timeout=0,
...                     parity=serial.PARITY_EVEN, rtscts=1)
>>> s = ser.read(100)       #read up to one hundred bytes
...                         #or as much is in the buffer

Get a Serial instance and configure/open it later

>>> ser = serial.Serial()
>>> ser.baudrate = 19200
>>> ser.port = 0
>>> ser
Serial<id=0xa81c10, open=False>(port='COM1', baudrate=19200, bytesize=8, parity='N', stopbits=1, timeout=None, xonxoff=0, rtscts=0)
>>> ser.open()
>>> ser.isOpen()
True
>>> ser.close()
>>> ser.isOpen()
False

Be carefully when using "readline". Do specify a timeout when opening the serial port otherwise it could block forever if no newline character is received. Also note that "readlines" only works with a timeout. "readlines" depends on having a timeout and interprets that as EOF (end of file). It raises an exception if the port is not opened correctly.
Do also have a look at the example files in the examples directory in the source distribution or online.

Examples

Please look in the SVN Repository. There is an example directory where you can find a simple terminal and more.
http://pyserial.svn.sourceforge.net/viewvc/pyserial/trunk/pyserial/examples/

Parameters for the Serial class

ser = serial.Serial(
    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
                            #if no port is specified an unconfigured
                            #an closed serial port object is created
    baudrate=9600,          #baudrate
    bytesize=EIGHTBITS,     #number of databits
    parity=PARITY_NONE,     #enable parity checking
    stopbits=STOPBITS_ONE,  #number of stopbits
    timeout=None,           #set a timeout value, None for waiting forever
    xonxoff=0,              #enable software flow control
    rtscts=0,               #enable RTS/CTS flow control
    interCharTimeout=None   #Inter-character timeout, None to disable
)

The port is immediately opened on object creation, if a port is given. It is not opened if port is None.
Options for read timeout:

timeout=None            #wait forever
timeout=0               #non-blocking mode (return immediately on read)
timeout=x               #set timeout to x seconds (float allowed)

Methods of Serial instances

open()                  #open port
close()                 #close port immediately
setBaudrate(baudrate)   #change baudrate on an open port
inWaiting()             #return the number of chars in the receive buffer
read(size=1)            #read "size" characters
write(s)                #write the string s to the port
flushInput()            #flush input buffer, discarding all it's contents
flushOutput()           #flush output buffer, abort output
sendBreak()             #send break condition
setRTS(level=1)         #set RTS line to specified logic level
setDTR(level=1)         #set DTR line to specified logic level
getCTS()                #return the state of the CTS line
getDSR()                #return the state of the DSR line
getRI()                 #return the state of the RI line
getCD()                 #return the state of the CD line

Attributes of Serial instances

Read Only:

portstr                 #device name
BAUDRATES               #list of valid baudrates
BYTESIZES               #list of valid byte sizes
PARITIES                #list of valid parities
STOPBITS                #list of valid stop bit widths

New values can be assigned to the following attribues, the port will be reconfigured, even if it’s opened at that time:

port                    #port name/number as set by the user
baudrate                #current baudrate setting
bytesize                #bytesize in bits
parity                  #parity setting
stopbits                #stop bit with (1,2)
timeout                 #timeout setting
xonxoff                 #if Xon/Xoff flow control is enabled
rtscts                  #if hardware flow control is enabled

Exceptions

serial.SerialException

Constants

parity:

serial.PARITY_NONE
    serial.PARITY_EVEN
    serial.PARITY_ODD

stopbits:

serial.STOPBITS_ONE
    serial.STOPBITS_TWO

bytesize:

serial.FIVEBITS
    serial.SIXBITS
    serial.SEVENBITS
    serial.EIGHTBITS