Com port interrupts again

[Chris Liechti]

engsol <engsolnorm at peak.org> wrote in 
news:154gu09bghnq674s2nqot9si6d50igueq7 at 4ax.com:

> I didn't fully think through my application before posting my
> question. Async com port routines to handle com port interrups
> only work well if one has access to the low level operating
> system. In that case the receive buffer interrupt would cause
> a jump to an interrupt service routine.. I don't believe that

i would not go that route... the operating system provides sync and async 
methods to access the serial port. it would make sense to use these before 
hacking the operating system. (also see below)

> Python provides that capabilty directly. The solution then would
> be to write a C extention?

ctypes can do many things without a C compiler. it's a very nice an 
valuable extension, but i won't like to encurage to use it for this 
particular problem.

> The suggestions offered by respondents to my original post
> were almost all of a "Use threads, and poll as needed" flavor.
> You're right...I need to learn threads as applied to com ports.

if you realy want to do async programming, have a look at twisted 
(http://twistedmatrix.com). it does not only provide async access to the 
serial port (trough pyserial + some code in twisted) it also delivers some 
nice utility functions, classes etc, like the reactor, defereds, thread 
pools (if you can't resist ;-) and many protocol handlers.

chris

-- 
Chris <cliechti at gmx.net>