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Re: How to set 250000 baud rate in pyserial ?

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On Fri, 26 Oct 2012 15:01:43 -0700 (PDT), kurabas@gmail.com declaimed
the following in gmane.comp.python.general:

> Error is like cannot set special baud rate.
> But as I said pyserial set this speed without problem  for ttyUSB0
> So it seems pyserial uses diefferent code depending of port type.

	Did you look at the source file?

	It doesn't know about "port type" -- it only differs by the OS in
use. Given the OS, the same system calls are invoked regardless of what
the device port "name" is.

-=-=-=-=- serialposix.py (extract)
if   plat[:5] == 'linux':    # Linux (confirmed)

    def device(port):
        return '/dev/ttyS%d' % port

    ASYNC_SPD_MASK = 0x1030
    ASYNC_SPD_CUST = 0x0030

    def set_special_baudrate(port, baudrate):
        import array
        buf = array.array('i', [0] * 32)

        # get serial_struct
        FCNTL.ioctl(port.fd, TERMIOS.TIOCGSERIAL, buf)

        # set custom divisor
        buf[6] = buf[7] / baudrate

        # update flags
        buf[4] &= ~ASYNC_SPD_MASK
        buf[4] |= ASYNC_SPD_CUST

        # set serial_struct
        try:
            res = FCNTL.ioctl(port.fd, TERMIOS.TIOCSSERIAL, buf)
        except IOError:
            raise ValueError('Failed to set custom baud rate: %r' %
baudrate)
-=-=-=-=-=-

	Practically all the other OS options (Mac, Sun, HP, Cygwin, etc.)
produce

    def set_special_baudrate(port, baudrate):
        raise ValueError("sorry don't know how to handle non standard
baud rate on this platform")


	Windows has its own module...
-- 
	Wulfraed                 Dennis Lee Bieber         AF6VN
        wlfraed@ix.netcom.com    HTTP://wlfraed.home.netcom.com/

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How to set 250000 baud rate in pyserial ? kurabas@gmail.com - 2012-10-25 04:09 -0700
  Re: How to set 250000 baud rate in pyserial ? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-10-25 14:11 -0400
    Re: How to set 250000 baud rate in pyserial ? Grant Edwards <invalid@invalid.invalid> - 2012-10-25 21:14 +0000
    Re: How to set 250000 baud rate in pyserial ? kurabas@gmail.com - 2012-10-26 15:01 -0700
      Re: How to set 250000 baud rate in pyserial ? Michael Torrie <torriem@gmail.com> - 2012-10-26 16:08 -0600
      Re: How to set 250000 baud rate in pyserial ? Dennis Lee Bieber <wlfraed@ix.netcom.com> - 2012-10-27 00:43 -0400
    Re: How to set 250000 baud rate in pyserial ? kurabas@gmail.com - 2012-10-26 15:01 -0700

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