Can Python serial support run at 45.45 baud?

John Nagle nagle at
Sun Feb 15 13:35:26 EST 2009

John Nagle wrote:
> MRAB wrote:
>> John Nagle wrote:
>> [snip]
>>> So the correct combination, 5 bits with 1.5 stop bits, isn't 
>>> supported in
>>> Python.  1 stop bit will not physically work on Baudot teletypes; the
>>> main camshaft doesn't come around fast enough.  (Yes, there's an actual
>>> mechanical reason for 1.5 stop bits.)  Requesting 2 stop bits at the
>>> Python level gets a reject at the Win32 level.  (Not sure why Win32
>>> doesn't allow that; extra stop bits just add delay, but don't hurt
>>> anything.  But it's not supported.)
>    I patched PySerial to support "STOPBITS_ONE5", for 1.5 stop bits,
> and the big Teletype Model 15 is now banging out text from Python.

   Logged in as a PySerial bug, with discussion of fix:

[ 2603052 ] 5-bit mode not properly supported on Windows

   Linux support for nonstandard baud rates is possible, but needs a
call to "setserial", which is not standard POSIX.

				John Nagle

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