[Tutor] Fwd: Re: Lost message re serial comms

[Mark Lawrence]

On 01/02/2015 14:28, Alan Gauld wrote:
> This was the problematic serial question.
>
> *From:*Doug Basberg [mailto:dbasberg at comcast.net]
> *Sent:* Friday, January 30, 2015 5:29 PM
> *To:* 'tudor at python.org'
> *Subject:* doing rs232 serial with binary data ?? with pyserial??
>
> Hello group;
>
> I am new to python and worked mostly in C & C++ (and assembly).  I do
> embedded controls and usually use the internet or LAN to log data and do
> controls.
>
> So, in Python I found pyserial and wish to use it to send binary to
> controlled devices (in this case to a Modbus protocol solar charge
> controller (TriStar TS-60).
>
> In C++ I would setup ‘structs’ or class attributes to hold the byte
> oriented commands and controller responses and then send them to rs232
> as binary.  I do not see how to do that with pyserial.
>
> What I need is to send and receive binary (not strings) over rs232.  In
> this case from/to a Raspberry Pi (RPI) controller to/from the solar
> charge controller.  The RPI runs apache server to handle the network.
>
> Any suggestions will be greatly appreciated.  I have been using
> Python2.7 so far.
>
> Thanks
>
> Doug
>

I'm no expert but I think you need the struct module from the standard 
library https://docs.python.org/2/library/struct.html#module-struct

This list is geared towards beginners to Python and/or programming.  If 
you try the struct module and run into problems please ask further 
questions on the main Python mailing list available at 
https://mail.python.org/mailman/listinfo/python-list, as 
gmane.comp.python.general or news:comp.lang.python

-- 
My fellow Pythonistas, ask not what our language can do for you, ask
what you can do for our language.

Mark Lawrence