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====================
Short introduction
====================
Opening serial ports
====================
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
Configuring ports later
=======================
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
Readline
========
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.
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