Async PySerial (was Re: pySerial Windows write problem)

[phil]

I use PySerial in a 16 line data collection system
with LOTS of threads, and yes am frustrated by read().
This sounds excellent, keep us updated.

BTW, haven't done any event driven Python except Tkinter.
Would this a class library  which would let you
define an event and a handler?

Do you have a one line code example?

Thanks.

Peter Hansen wrote:

> Neil Benn wrote:
> 
>>PySerial doesn;t have any kind of event firing to notify you when data 
>>is available.  The way I get round this is to have a loop polling (in a 
>>seperate thread) to see if any data is available (it's a method on the 
>>interface), then read all the data in and fire this off to my 
>>listeners/observers with the read data.  
>>
> 
> On that note, I've got a preliminary version of something I call "Bent" 
> (think "slightly Twisted") which is focused for now on providing an 
> asynchronous version of PySerial which is designed around the 
> event-driven model instead of its current polled scheme.
> 
> It shares a number of features with the Twisted-based PySerial port 
> (also done by Chris Liechti, for the Twisted team, judging by the code 
> comments) but doesn't require one to adopt the whole Twisted framework. 
>   Basically it provides you with the equivalent of one "reactor" per 
> thread for PySerial stuff.  On Win32 only for now.  There are other 
> limitations too.  Not ready for prime time.
> 
> On the plus side, it's been letting me convert my serial stuff to be 
> fully event-driven and with the resulting much lower latencies and 
> better CPU efficiency, while keeping my code more "traditional" instead 
> of having to force it entirely into the Twisted point of view.
> 
> Just an FYI.  And, obviously, to hear back from those interested.  I 
> don't know if this is something that should be contributed to the 
> PySerial project (it's more of a rewrite than an add-on), or set up as a 
> new project, or passed around quietly behind the scenes for a while.
> No docs yet, no contrived examples (but various pieces of working code 
> in real daily use).  Did I mention it wasn't ready for prime time?
> 
> If you've ever been annoyed having to do .read(1) to get characters one 
> at a time in PySerial, or .read(100) with a timeout, or whatever, this 
> might be of interest to you...
> 
> -Peter
>