On Mar 10, 1:07 pm, "Gabriel Genellina" <gagsl-...@yahoo.com.ar>
wrote:
> En Tue, 09 Mar 2010 12:01:22 -0300, kishore <kishorei...@gmail.com>
> escribió:
>
>
>
>
>
> >> > Iam using python 2.5.4
> >> > pyserial 2.4
> >> > pywin32-214
> >> > on windows 7
>
> >> > i hav a small test script written to query a serial device (arduino)
> >> > and get back reply appropriately
>
> > Thanks for your response
> > i tried closing idle and the following code prints
> > port opened
> > Write failed
>
> > code:
>
> > import serial
> > import time
> > ser=serial.Serial(port='\\.\COM2', baudrate=9600)
>
> If you want a string containing these 8 characters \\.\COM2 you have to
> write it either as r'\\.\COM2' or '\\\\.\\COM2'
>
> > if ser:
> > print 'port opened'
>
> Either the Serial object is constructed and returned, or an exception is
> raised. 'if ser:' has no sense; Python is not C...
>
> > ser.open()
> > if ser.write('1'):
> > print 'Write success'
> > else:
> > print 'write failed'
>
> The write method, when successful, implicitly returns None. None has a
> false boolean value, so your code will always print 'write failed'.
>
> Usually, in Python, error conditions are marked by raising an exception.
> Using return values to indicate success/failure is uncommon.
>
> Also, are you sure the device doesn't expect a newline character? '1\n'?
>
> You may need to call ser.flushOutput() to ensure the output buffer is
> actually emptied.
>
> > time.sleep(1)
> > a=ser.readline()
>
> print repr(a)
>
> > time.sleep(1)
> > b=ser.readline()
>
> print repr(b)
>
> > ser.close()
> > I believe this might be a serial port access error.
> > how to solve this?
> > Any suggestions?
>
> I don't think so. If you could not access the serial port, you'd have seen
> an IOError exception or similar.
>
> --
> Gabriel Genellina
thanks Gabriel & Andy..ll get back soon here after trying ur
suggestions
--
http://mail.python.org/mailman/listinfo/python-list
