[python-win32] Python - connexion to serial port

[Paul.Koning at dell.com]

> On Jan 11, 2018, at 11:36 AM, Dennis Lee Bieber <wlfraed at ix.netcom.com> wrote:
> 
> On Thu, 11 Jan 2018 15:12:33 +0000, "Schoeni, Yann"
> <Yann.Schoeni at moutier.ch> declaimed the following:
> 
>> I've a web application which needs to send data to a serial port. The webserver uses ajax to send data to a python script.
>> 
>> The Python script uses the serial module to open, send data, and close the serial port.
>> 
>> Is there a way to keep the serial port open ?
>> 
>> Because for now, I open/close it between each transaction and I need to be 100% sure the data package will be send .. which is not the case with my actual python script.

I'd add one observation: while you can be reasonably sure that data is sent if you ask the serial port to send it, that does NOT mean it will be received.  I suspect what is actually needed is a guarantee that the data is received.

A serial port does not offer that guarantee.  If the hardware is clean, it only offers a high probability.  If you want guarantees, you need a data checking and acknowledgement protocol, like DDCMP or TCP or DECnet.

	paul